android programming 1

this slides explain how to use android's activity and views

Transcript

1. Android Programming MVC and Activities
2. Little taste of MVC ›  Architectural pattern Controller Model View Android Programming
3. What do you see here? Android Programming
4. First level: Activity A single, Task- focused, window. Android Programming
5. Activity Lifecycle ›  More details on: developers.android.com Android Programming
6. What do you deeper see here? Android Programming
7. Second level: Views Every “brick” placed in your Activity. Examples (javaàAndroid): ›  JLabelàTextView ›  JButtonàButton ›  FlowLayoutàLinearLayout
8. Activity UI <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http:// schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content" > <TextView android:id="@+id/tv1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello World!" /> </RelativeLayout> Android Programming
9. Activity Logic public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } @Override protected void onPause() { // TODO Auto-generated method stub super.onPause(); } } Android Programming
10. Referencing View TextView tv = (TextView) findViewById(R.id.tv1); Android Programming
11. Manifest File <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.firstapp” android:versionCode="1” android:versionName="1.0" > <uses-sdk android:minSdkVersion=”7” android:targetSdkVersion="16" /> <application android:icon="@drawable/ic_launcher” android:label="@string/app_name”> <activity android:name="com.example.firstapp.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> Android Programming
12. Working with Activities //first Activity Intent i = new Intent (MainActivity.this, NewActivity.class); i.putExtra("key", "value"); //called Activity Intent launcher = getIntent(); launcher.getExtras().getString("key"); Android Programming
13. What should we do today? When the user clicks the button another activity will start. The second activity shows username and password Android Programming
14. Credit: ›  Groveshark images ›  Activity lifecycle Android Programming