Kotlin for Android

Kotlin for Android is now officially supported by Google, in this presentation we explore some of the cool features of the language. Also, we take some time to introduce new-comers to Android Development.

Transcript

1. Kotlin for Android Jorge E. Hernández
 @lalongooo
 Android Engineer
2. Android?
3. A 5 minutes introduction // school_file.xml
4. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 </school> // school_file.xml
5. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 <student /> </school> // school_file.xml
6. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan”/> </school> // school_file.xml
7. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> </school> // school_file.xml
8. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml
9. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml <?xml version="1.0" encoding="utf-8"?> <library>
 </library>
 
 
 // library_file.xml
10. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
11. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
12. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school>
 <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
13. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:=““> <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
14. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=““> <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
15. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=“http://example.com/schema/myschool“> <student name=“Juan” last_name=“Perez”/> <classroom name=“VIP Classroom”/> <teacher name=“El Barco”/> </school> // school_file.xml // library_file.xml
16. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library>
 <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=“http://example.com/schema/myschool“> <student s:name=“Juan” s:last_name=“Perez”/> <classroom s:name=“VIP Classroom”/> <teacher s:name=“El Barco”/> </school> // school_file.xml // library_file.xml
17. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library
 xmlns:l=“http://example.com/schema/mylibrary“> <book
 name=“Fifty shades of Grey”/> <student
 name=“José García”/> <author
 name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=“http://example.com/schema/myschool“> <student s:name=“Juan” s:last_name=“Perez”/> <classroom s:name=“VIP Classroom”/> <teacher s:name=“El Barco”/> </school> // school_file.xml // library_file.xml
18. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library
 xmlns:l=“http://example.com/schema/mylibrary“> <book
 l:name=“Fifty shades of Grey”/> <student
 l:name=“José García”/> <author
 l:name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=“http://example.com/schema/myschool“> <student s:name=“Juan” s:last_name=“Perez”/> <classroom s:name=“VIP Classroom”/> <teacher s:name=“El Barco”/> </school> // school_file.xml // library_file.xml
19. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library
 xmlns:miau=“http://example.com/schema/mylibrary“> <book
 miau:name=“Fifty shades of Grey”/> <student
 miau:name=“José García”/> <author
 miau:name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:guau=“http://example.com/schema/myschool“> <student guau:name=“Juan” guau:last_name=“Perez”/> <classroom guau:name=“VIP Classroom”/> <teacher guau:name=“El Barco”/> </school> // school_file.xml // library_file.xml
20. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <library
 xmlns:l=“http://example.com/schema/mylibrary“> <book
 l:name=“Fifty shades of Grey”/> <student
 l:name=“José García”/> <author
 l:name=“E. L. James”/> </library> <?xml version="1.0" encoding="utf-8"?> <school
 xmlns:s=“http://example.com/schema/myschool“> <student s:name=“Juan” s:last_name=“Perez”/> <classroom s:name=“VIP Classroom”/> <teacher s:name=“El Barco”/> </school> // school_file.xml // library_file.xml
21. A 5 minutes introduction
22. A 5 minutes introduction Button TextView
23. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout> </android.support.constraint.ConstraintLayout> // my_screen.xml
24. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout android:layout_width="match_parent"> </android.support.constraint.ConstraintLayout> // my_screen.xml
25. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.constraint.ConstraintLayout> // my_screen.xml
26. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.constraint.ConstraintLayout> // my_screen.xml
27. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.constraint.ConstraintLayout> // my_screen.xml
28. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button /> </android.support.constraint.ConstraintLayout> // my_screen.xml
29. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
30. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
31. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
32. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
33. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
34. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView /> </android.support.constraint.ConstraintLayout> // my_screen.xml
35. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
36. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
37. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!"/> </android.support.constraint.ConstraintLayout> // my_screen.xml
38. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
39. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
40. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
41. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
42. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
43. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
44. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
45. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
46. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
47. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
48. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
49. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
50. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
51. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout> // my_screen.xml
52. A 5 minutes introduction // my_screen.xml <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout>
53. A 5 minutes introduction
54. A 5 minutes introduction Activities Services, Permissions
55. A 5 minutes introduction MyClass.java
 MyClass.kt
56. A 5 minutes introduction Android Tests: - Clicks (taps) - Swipes - Pinch (zoom) Instrumentation tests “Espresso”
57. A 5 minutes introduction Unit Tests: - Classes - Methods JUnit
58. A 5 minutes introduction Pictures, images, icons.
 ¡NOT LAUNCHER ICONS!
59. A 5 minutes introduction Screens layouts
 (XML files)
60. A 5 minutes introduction Menu options
 (XML files)
61. A 5 minutes introduction Launcher icons
62. A 5 minutes introduction
63. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> </resources>
64. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources>
65. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> </resources>
66. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
67. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> </resources>
68. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
69. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout>
70. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
71. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
72. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources>
73. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources>
74. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources>
75. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
76. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
77. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
78. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
79. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
80. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
81. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height="wrap_content" android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
82. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
83. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name=“btn_height">100dp</dimen> </resources>
84. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
85. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
86. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text="Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
87. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text=“Click me" app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
88. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text=“@string/btn_text“ app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
89. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text=“@string/btn_text“ app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=“@string/hello“ android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name=“hello">Hello World!</string> </resources>
90. A 5 minutes introduction <Button android:id="@+id/myButton" android:layout_width=“@dimen/btn_width" android:layout_height=“@dimen/btn_height” android:text=“@string/btn_text“ app:layout_constraintBottom_toTopOf="@+id/myTextView" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=“@string/hello“ android:textColor=“@color/red" android:textSize="56sp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" />
91. my_screen.xml colors.xml dimens.xml strings.xml A 5 minutes introduction
92. my_screen.xml colors.xml dimens.xml strings.xml A 5 minutes introduction
93. Questions?
94. my_screen.xml colors.xml dimens.xml strings.xml A 5 minutes introduction
95. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources> colors.xml
96. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources> colors.xml public final class R { public static final class color { }} }}
97. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources> colors.xml public final class R { public static final class color { }} }}
98. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources> colors.xml public final class R { public static final class color { public static final int red=0x7f050002; public static final int green=0x7f050003; public static final int blue=0x7f050004; }} }}
99. A 5 minutes introduction <?xml version="1.0" encoding="utf-8"?> <resources> <color name="red">#FF0000</color> <color name="green">#00FF00</color> <color name="blue">#0000FF</color> </resources> colors.xml R.color.red R.color.green R.color.blue public final class R { public static final class color { public static final int red=0x7f050002; public static final int green=0x7f050003; public static final int blue=0x7f050004; }} }}
100. A 5 minutes introduction dimens.xml <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
101. A 5 minutes introduction dimens.xml public final class R { public static final class dimen { public static final int btn_width=0x7f030004; public static final int btn_height=0x7f050002; }} }} <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
102. A 5 minutes introduction dimens.xml R.dimen.btn_width R.dimen.btn_height public final class R { public static final class dimen { public static final int btn_width=0x7f030004; public static final int btn_height=0x7f050002; }} }} <?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="btn_width">180dp</dimen> <dimen name="btn_height">100dp</dimen> </resources>
103. A 5 minutes introduction strings.xml
104. A 5 minutes introduction strings.xml <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
105. A 5 minutes introduction strings.xml <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources> public final class R { public static final class string { public static final int btn_text=0x7f05001e; public static final int hello=0x7f050030; }} }}
106. A 5 minutes introduction strings.xml R.string.btn_text R.string.hello public final class R { public static final class string { public static final int btn_text=0x7f05001e; public static final int hello=0x7f050030; }} }} <?xml version="1.0" encoding="utf-8"?> <resources> <string name="btn_text">Click me</string> <string name="hello">Hello World!</string> </resources>
107. A 5 minutes introduction my_screen.xml <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
108. A 5 minutes introduction my_screen.xml public final class R { public static final class layout { public static final int my_screen=0x7f64003e; }} }} <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
109. A 5 minutes introduction my_screen.xml R.layout.my_screen public final class R { public static final class layout { public static final int my_screen=0x7f64003e; }} }} <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
110. A 5 minutes introduction my_screen.xml <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
111. A 5 minutes introduction my_screen.xml public final class R { public static final class id { public static final int myButton=0x7f64003e; public static final int myTextView=0x7f64003e; }} }} <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
112. A 5 minutes introduction my_screen.xml R.id.myButton R.id.myTextView public final class R { public static final class id { public static final int myButton=0x7f64003e; public static final int myTextView=0x7f64003e; }} }} <?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <Button android:id="@+id/myButton" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <TextView android:id="@+id/myTextView" android:layout_width="wrap_content" android:layout_height="wrap_content"/> </android.support.constraint.ConstraintLayout>
113. A 5 minutes introduction
114. A 5 minutes introduction class MyActivity {{ }}
115. A 5 minutes introduction class MyActivity : Activity() {{ }}
116. A 5 minutes introduction import android.app.Activity class MyActivity : Activity() {{ }}
117. A 5 minutes introduction import android.app.Activity class MyActivity : Activity() {{ override fun onCreate() { }} }}
118. A 5 minutes introduction import android.app.Activity class MyActivity : Activity() {{ override fun onCreate(savedInstanceState: Bundle?) { }} }}
119. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() {{ override fun onCreate(savedInstanceState: Bundle?) { }} }}
120. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() {{ override fun onCreate(savedInstanceState: Bundle?) { super.onCreate() }} }}
121. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() {{ override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) }} }}
122. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() {{ override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView() }} }}
123. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }}
124. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }}
125. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
126. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
127. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
128. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
129. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate() { }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate() { }} }} MainActivity.kt MainActivity.java
130. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { }} }} MainActivity.kt MainActivity.java
131. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
132. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} import android.app.Activity import android.os.Bundle public class MyActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_screen); }} }} MainActivity.kt MainActivity.java
133. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) }} }} MainActivity.kt
134. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById() }} }} MainActivity.kt
135. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>() }} }} MainActivity.kt
136. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton) }} }} MainActivity.kt
137. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { }} }} }} MainActivity.kt
138. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if () { }} }} }} }} MainActivity.kt
139. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if () { // Hide }} }} }} }} MainActivity.kt
140. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if () { // Hide } else { // Show }} }} }} }} MainActivity.kt
141. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>()) { // Hide } else { // Show }} }} }} }} MainActivity.kt
142. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView)) { // Hide } else { // Show }} }} }} }} MainActivity.kt
143. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { // Hide } else { // Show }} }} }} }} MainActivity.kt
144. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { findViewById<View>(R.id.myTextView).visibility = View.INVISIBLE } else { // Show }} }} }} }} MainActivity.kt
145. A 5 minutes introduction import android.app.Activity import android.os.Bundle class MyActivity : Activity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.my_screen) findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { findViewById<View>(R.id.myTextView).visibility = View.INVISIBLE } else { findViewById<View>(R.id.myTextView).visibility = View.VISIBLE }} }} }} }} MainActivity.kt
146. A 5 minutes introduction findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { findViewById<View>(R.id.myTextView).visibility = View.INVISIBLE } else { findViewById<View>(R.id.myTextView).visibility = View.VISIBLE }} }} MainActivity.kt findViewById(R.id.myButton).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (findViewById(R.id.myTextView).getVisibility() == View.VISIBLE) { findViewById(R.id.myTextView).setVisibility(View.INVISIBLE); } else { findViewById(R.id.myTextView).setVisibility(View.VISIBLE); }} }} }); MainActivity.java
147. A 5 minutes introduction findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { findViewById<View>(R.id.myTextView).visibility = View.INVISIBLE } else { findViewById<View>(R.id.myTextView).visibility = View.VISIBLE }} }} MainActivity.kt findViewById(R.id.myButton).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (findViewById(R.id.myTextView).getVisibility() == View.VISIBLE) { findViewById(R.id.myTextView).setVisibility(View.INVISIBLE); } else { findViewById(R.id.myTextView).setVisibility(View.VISIBLE); }} }} }); MainActivity.java
148. A 5 minutes introduction findViewById<View>(R.id.myButton).setOnClickListener { if (findViewById<View>(R.id.myTextView).visibility == View.VISIBLE) { findViewById<View>(R.id.myTextView).visibility = View.INVISIBLE } else { findViewById<View>(R.id.myTextView).visibility = View.VISIBLE }} }} MainActivity.kt findViewById(R.id.myButton).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (findViewById(R.id.myTextView).getVisibility() == View.VISIBLE) { findViewById(R.id.myTextView).setVisibility(View.INVISIBLE); } else { findViewById(R.id.myTextView).setVisibility(View.VISIBLE); }} }} }); MainActivity.java
149. Questions?
150. Kotlin Appeared in 2011 Created by JetBrains JetBrains develops IntelliJ, PyCharm, WebStorm Runs on the JVM •Clojure •Groovy •JRuby •Jython •Scala Officially supported by Google
151. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { }} public class MyClass { }}
152. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello() { return "" }} }} public class MyClass { }}
153. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello(name: String) { return "" }} }} public class MyClass { }}
154. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello(name: String): String { return "" }} }} public class MyClass { }}
155. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello(name: String): String { return "Hello !" }} }} public class MyClass { }}
156. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello(name: String): String { return "Hello $name!" }} }} public class MyClass { }}
157. A 5 minutes introduction MyClass.java MyClass.kt class MyClass { fun sayHello(name: String): String { return "Hello $name!" }} }} public class MyClass { public String sayHello(String name) { return "Hello " + name + "!"; }} }}
158. A 5 minutes introduction MyClass.java MyClass.kt fun circleArea(radius: Double): Double { val PI = 3.1416 return PI * Math.pow(radius, 2.0) / 2 }} public double circleArea(double radius) { double PI = 3.1416; return (PI * Math.pow(radius, 2.0)) / 2; }}
159. A 5 minutes introduction MyClass.java MyClass.kt fun circleArea(radius: Double): Double { var PI = 3.1416 return PI * Math.pow(radius, 2.0) / 2 }} public double circleArea(double radius) { double PI = 3.1416; return (PI * Math.pow(radius, 2.0)) / 2; }}
160. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
161. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
162. Kotlin vs Java fun concatName(name: String, last: String): String { return "$name $last" }} MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }}
163. Kotlin vs Java fun concatName(name: String?, last: String?): String? { return "$name $last" }} MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }}
164. Kotlin vs Java fun concatName(name: String!, last: String!): String? { return "$name $last" }} MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }}
165. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
166. Kotlin vs Java MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }} class MyClass { fun sayHello(name: String, last: String): String { MyClass obj = MyClass() return "Hello ${obj.concat(name)}!” }} }}
167. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
168. Kotlin vs Java Extensions.kt fun String.appendA(): String { return this.plus("A") } AnyClass.kt fun useExtensionFunction(anyString: String): String { return anyString.appendA() }
169. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
170. A 5 minutes introduction MyClass.java MyClass.kt fun handleString(text: Any): String? { if (text is String) { return "$text other value" } else { return null } } public String handleString(Object text) { if (text instanceof String) { return ((String) text).concat(" other value"); } else { return null; } }
171. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
172. Kotlin vs Java fun concatName(name: String, last: String): String { return "$name $last" }} MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }}
173. Kotlin vs Java fun concatName(name: String, last: String): String { return "$name $last" }} MyClass.java MyClass.kt public String concatName(String name, String last) { if (name != null && last != null) { return name.concat(" ").concat(last); } else { return null; }} }}
174. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
175. Kotlin vs Java Address.kt val address : Address = Address() address.state = "bar" address.street = "bar" address.city = "bar" address.zip = "bar" class Address { var name: String = "foo" var street: String = "foo" var city: String = "foo" var state: String = "foo" var zip: String = "foo" }
176. Kotlin vs Java Address.kt val what = address.state class Address { val name: String = "foo" val street: String = "foo" val city: String = "foo" val state: String = "foo" val zip: String = "foo" } // read only
177. Kotlin vs Java public class Address { String state; String street; String city; String zip; public String getState() { return state; } public void setState(String state) { this.state = state; } public String getStreet() { return street; } public void setStreet(String street) { this.street = street; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getZip() { return zip; } public void setZip(String zip) { this.zip = zip; } }
178. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
179. Kotlin vs Java val age = 13 val name = "Elon" val girls: Int = 7 val place: String = "Home"
 
 
 
 MyClass.kt
180. Kotlin vs Java val age = 13 val name = "Elon" val girls: Int = 7 val place: String = "Home"
 
 
 
 int age = 13; String name = "Elon"; MyClass.kt MyClass.java
181. Kotlin vs Java Null safe Interoperable with Java Extension functions Smart casts String templates Properties (getter/setters in Java) Type inference Data classes Range expressions
182. Thanks @lalongooo