PERFMATTERS for Android - DroidCon VIenna 2016

The slogan '#PERFMATTERS' by Colt McAnlis is one of the most important statements, which an Android developer should follow. A well performing application makes the difference between a nice looking application and one, which gets successful. You, as an Android developer, have the responsibility to delight your users, so they don't feel how much work your application has to burden to fulfill the user's needs. This session will show you some easy optimizations and how to avoid glitches in the application. A lot of developers would shout, that this is premature optimization. In contrary it is preventive. With a small amount of work while developing you can avoid a lot of pitfalls. You will hopefully have a better understanding of the underlying system afterwards. During the session some tools and frameworks will be presented for helping you to fulfill your mission.

Transcript

1. #DroidconAT
   www.immobilienscout24.de
   Hasan Hosgel – Droidcon Vienna 2016
   #PERFMATTERS
   for Android
   

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2. #DroidconAT #PERFMATTERS for Android | Hasan Hosgel
   Immobilien Scout GmbH
   Location: Berlin
   Employees: ~ 520
   > 850.000 ads per month
   > 787 M visits in 2014*
   > 6 M Android downloads
   *source: comScore Digital Analytix,
   January 2015,
   complete IS24 (Portal & Mobile)
   

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3. #DroidconAT
   Why we are developers?
   

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4. #DroidconAT
   Why we are developers?
   ESPECIALLY ANDROID
   

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5. Source: https://www.flickr.com/photos/theinfamousgdub/1765952198
   

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6. We are smart!
   Source: https://www.flickr.com/photos/theinfamousgdub/1765952198
   

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7. Source: http://giphy.com/gifs/apple-looney-tunes-android-4A41Wn7C32RiM
   

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8. We Love Android!
   Source: http://giphy.com/gifs/apple-looney-tunes-android-4A41Wn7C32RiM
   

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9. Source: Photo by Sujaki-F
   

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10. We have Passion!
    Source: Photo by Sujaki-F
    

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11. We have Passion!
    Source: Photo by Sujaki-F
    

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12. We have Passion!
    Source: Photo by Sujaki-F
    We Love Challenges
    

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13. Source: https://www.flickr.com/photos/68751915@N05/6793826885
    

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14. We Love Money
    Source: https://www.flickr.com/photos/68751915@N05/6793826885
    

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15. Source: http://agenciabrasil.ebc.com.br/geral/foto/2014-07/cerimonia-de-premiacao-da-copa-do-mundo-no-brasil
    

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16. We love to delight our
    users
    Source: http://agenciabrasil.ebc.com.br/geral/foto/2014-07/cerimonia-de-premiacao-da-copa-do-mundo-no-brasil
    

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17. #DroidconAT
    User Expectations
    

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18. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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19. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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20. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    • 49% app start < 2 s
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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21. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    • 49% app start < 2 s
    Users are intolerant of issues and are quick to uninstall mobile
    apps
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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22. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    • 49% app start < 2 s
    Users are intolerant of issues and are quick to uninstall mobile
    apps
    • 80% three attempts or less
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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23. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    • 49% app start < 2 s
    Users are intolerant of issues and are quick to uninstall mobile
    apps
    • 80% three attempts or less
    • 53% apps with severe issues like crashes, freezes or errors
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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24. #DroidconAT
    User Expectations
    Mobile App Users are impatient
    • 61% app start < 4 s
    • 49% app start < 2 s
    Users are intolerant of issues and are quick to uninstall mobile
    apps
    • 80% three attempts or less
    • 53% apps with severe issues like crashes, freezes or errors
    • 36% heavy battery usage
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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25. #DroidconAT
    User Expectations
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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26. #DroidconAT
    User Expectations
    Users blame the app and the company who made it
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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27. #DroidconAT
    User Expectations
    Users blame the app and the company who made it
    • 55% app is responsible for performance issues
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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28. #DroidconAT
    User Expectations
    Users blame the app and the company who made it
    • 55% app is responsible for performance issues
    • 37% Stated that app crashes or errors make them think less of a company’s brand
    Source: https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
    

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29. #DroidconAT
    Performance Impacts
    

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30. #DroidconAT
    Performance Impacts
    500 ms delay
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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31. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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32. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    1,000 ms delay
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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33. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    1,000 ms delay
    bounce rate -8.3% -- Conversion rate -3.5%
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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34. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    1,000 ms delay
    bounce rate -8.3% -- Conversion rate -3.5%
    100ms delay mean for Amazon -1%
    revenue
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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35. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    1,000 ms delay
    bounce rate -8.3% -- Conversion rate -3.5%
    100ms delay mean for Amazon -1%
    revenue
    11% scream at their device
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    

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36. #DroidconAT
    Performance Impacts
    500 ms delay
    bounce rate -4.7% -- conversion rate -1.9%
    1,000 ms delay
    bounce rate -8.3% -- Conversion rate -3.5%
    100ms delay mean for Amazon -1%
    revenue
    11% scream at their device
    4 % throw their phones
    Source: http://www.mobilejoomla.com/media/press/responsive-vs-serverside/Responsive-Design-vs-
    Server-Side-Solutions-Infographic.jpg
    https://www.flickr.com/photos/9009139@N08/1263954
    439
    

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37. View Slide

38. Source: http://giphy.com/gifs/sad-kawaii-pretty-10XOyCb09KyjLy
    

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39. #DroidconAT
    www.immobilienscout24.de
    Let‘s find some performance improvements
    

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40. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    

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41. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    

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42. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Keep the work of the main
    thread à ANR
    

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43. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Keep the work of the main
    thread à ANR
    • Avoid GPU overdrawings
    • https://www.youtube.com/watc
    h?v=T52v50r-JfE
    

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44. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Keep the work of the main
    thread à ANR
    • Avoid GPU overdrawings
    • https://www.youtube.com/watc
    h?v=T52v50r-JfE
    • Avoid nested multi-pass
    layouts
    • http://goo.gl/Q5te24
    

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45. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Keep the work of the main
    thread à ANR
    • Avoid GPU overdrawings
    • https://www.youtube.com/watc
    h?v=T52v50r-JfE
    • Avoid nested multi-pass
    layouts
    • http://goo.gl/Q5te24
    • Consider RenderScript for
    performance critical code
    

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46. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    

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47. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Do not allocate memory inside
    onDraw()
    

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48. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Do not allocate memory inside
    onDraw()
    • Avoid Leaks
    

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49. #DroidconAT
    LeakCanary to the Rescue
    https://github.com/square/leakcan
    ary
    

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50. #DroidconAT
    Setup LeakCanary
    debugCompile 'com.squareup.leakcanary:leakcanary-android:1.3.1'
    releaseCompile 'com.squareup.leakcanary:leakcanary-android-no-op:1.3.1’
    build.gradle
    public class DcAtApplication extends Application {
    @Override
    public void onCreate() {
    super.onCreate();
    LeakCanary.install(this);
    }
    }
    DcAtApplication.java
    

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51. #DroidconAT
    Use Your Debug Build Normally
    

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52. #DroidconAT
    Analyze Memory
    

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53. #DroidconAT
    Analyze Heap Dump
    

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54. #DroidconAT
    Analyze Heap Dump
    

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55. #DroidconAT
    Analyze Heap Dump since AS 1.5
    

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56. #DroidconAT
    Analyze Memory
    

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57. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Do not allocate memory inside
    onDraw()
    • Avoid Leaks
    • Avoid listener à EventBus
    

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58. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Do not allocate memory inside
    onDraw()
    • Avoid Leaks
    • Avoid listener à EventBus
    • Use SparseArray* family
    instead of JDK Collections/
    Maps
    

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59. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Do not allocate memory inside
    onDraw()
    • Avoid Leaks
    • Avoid listener à EventBus
    • Use SparseArray* family
    instead of JDK Collections/
    Maps
    • Be aware that enums need
    more resource, but use them, if
    it will make sense for you
    

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60. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    

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61. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Activate gzip compression on
    incoming and outgoing
    network traffic or FlatBuffer
    

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62. #DroidconAT
    Analyze First Start
    

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63. #DroidconAT
    Analyze Second Start
    

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64. #DroidconAT
    Analyze Second Start
    

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65. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Activate gzip compression on
    incoming and outgoing
    network traffic or FlatBuffer
    • Cache data on disk (image,
    http responses) with
    reasonable TTL
    

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66. #DroidconAT
    Finally Second Start
    

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67. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Activate gzip compression on
    incoming and outgoing
    network traffic or FlatBuffer
    • Cache data on disk (image,
    http responses) with
    reasonable TTL
    • Server side cache headers like
    ETag & Last-Modified
    

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68. #DroidconAT
    Possible improvements
    CPU
    Memory
    I/O
    • Activate gzip compression on
    incoming and outgoing
    network traffic or FlatBuffer
    • Cache data on disk (image,
    http responses) with
    reasonable TTL
    • Server side cache headers like
    ETag & Last-Modified
    • Use JobScheduler API to batch
    across system or better use
    push notifications for update
    information
    

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69. Source: http://www.flickr.com/photos/16210667@N02/9172895225
    

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70. #DroidconAT
    Optimizing ArrayList
    

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71. #DroidconAT
    Optimizing ArrayList
    public List getDcAtNames(List attendees) {
    List names = new ArrayList<>();
    for (Attendee attendee : attendees) {
    names.add(attendee.name);
    }
    return names;
    }
    JAVA
    

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72. #DroidconAT
    Optimizing ArrayList
    public List getDcAtNames(List attendees) {
    List names = new ArrayList<>(attendees.size());
    for (Attendee attendee : attendees) {
    names.add(attendee.name);
    }
    return names;
    }
    JAVA
    

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73. #DroidconAT
    Optimizing ArrayList
    @Override public boolean add(E object) {
    Object[] a = array;
    int s = size;
    if (s == a.length) {
    Object[] newArray = new Object[s +
    (s < (MIN_CAPACITY_INCREMENT / 2) ?
    MIN_CAPACITY_INCREMENT : s >> 1)];
    System.arraycopy(a, 0, newArray, 0, s);
    array = a = newArray;
    }
    a[s] = object;
    size = s + 1;
    modCount++;
    return true;
    }
    JAVA
    

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74. #DroidconAT
    Optimizing ArrayList
    void addDcAtSpeaker(ArrayList attendees, List speakers) {
    for (String speaker : speakers) {
    attendees.add(speaker);
    }
    }
    JAVA
    

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75. #DroidconAT
    Optimizing ArrayList
    void addDcAtSpeaker(ArrayList attendees, List speakers) {
    attendees.ensureCapacity(attendees.size() + speakers.size());
    for (String speaker : speakers) {
    attendees.add(speaker);
    }
    }
    JAVA
    

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76. #DroidconAT
    Optimizing Bundle
    

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77. #DroidconAT
    Optimizing Bundle
    public static DcAtScheduleFragment instance(int startMode) {
    final DcAtScheduleFragment fragment = new DcAtScheduleFragment();
    final Bundle bundle = new Bundle();
    bundle.putInt(START_MODE, startMode);
    fragment.setArguments(bundle);
    return fragment;
    }
    JAVA
    

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78. #DroidconAT
    Optimizing Bundle
    public static DcAtScheduleFragment instance(int startMode) {
    final DcAtScheduleFragment fragment = new DcAtScheduleFragment();
    final Bundle bundle = new Bundle(1);
    bundle.putInt(START_MODE, startMode);
    fragment.setArguments(bundle);
    return fragment;
    }
    JAVA
    

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79. #DroidconAT
    Optimizing StringBuilder
    

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80. #DroidconAT
    Optimizing StringBuilder
    public StringBuilder getDcAtNames(List names) {
    StringBuilder builder = new StringBuilder();
    for (String name : names) {
    if (builder.length() > 0) {
    builder.append(", ");
    }
    builder.append(name);
    }
    return builder;
    }
    JAVA
    

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81. #DroidconAT
    Optimizing StringBuilder
    public StringBuilder getDcAtNames(List names) {
    StringBuilder builder = new StringBuilder(names.size() * 13);
    for (String name : names) {
    if (builder.length() > 0) {
    builder.append(", ");
    }
    builder.append(name);
    }
    return builder;
    }
    JAVA
    

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82. #DroidconAT
    Optimizing StringBuilder
    final void append0(char[] chars) {
    int newCount = count + chars.length;
    if (newCount > value.length) {
    enlargeBuffer(newCount);
    }
    System.arraycopy(chars, 0, value, count, chars.length);
    count = newCount;
    }
    JAVA
    

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83. #DroidconAT
    Optimizing StringBuilder
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    names.ensureCapacity(names.length() + organizers.size() * 13);
    for (String organizer : organizers) {
    if (names.length() > 0) {
    names.append(", ");
    }
    names.append(organizer);
    }
    }
    JAVA
    

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84. #DroidconAT
    Optimizing Loops
    

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85. #DroidconAT
    Optimizing Moar – The Loop
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    names.ensureCapacity(names.length() + organizers.size() * 13);
    for (String organizer : organizers) {
    if (names.length() > 0) {
    names.append(", ");
    }
    names.append(organizer);
    }
    }
    JAVA
    

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86. #DroidconAT
    Optimizing Moar – The Loop
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    names.ensureCapacity(names.length() + organizers.size() * 13);
    for (int i = 0; i < organizers.size(); i++) {
    String organizer = organizers.get(i);
    if (names.length() > 0) {
    names.append(", ");
    }
    names.append(organizer);
    }
    }
    JAVA
    

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87. #DroidconAT
    Optimizing Moar – The Loop
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    names.ensureCapacity(names.length() + organizers.size() * 13);
    for (int i = 0, organizersSize = organizers.size(); i < organizersSize; i++) {
    String organizer = organizers.get(i);
    if (names.length() > 0) {
    names.append(", ");
    }
    names.append(organizer);
    }
    }
    JAVA
    

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88. #DroidconAT
    Optimizing Moar – The Loop
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    final int size = organizers.size();
    names.ensureCapacity(names.length() + size * 13);
    for (int i = 0; i < size; i++) {
    String organizer = organizers.get(i);
    if (names.length() > 0) {
    names.append(", ");
    }
    names.append(organizer);
    }
    }
    JAVA
    

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89. #DroidconAT
    Optimizing Moar – The Loop
    public StringBuilder addDcAtOrganizer(StringBuilder names, List organizers)
    {
    final int size = organizers.size();
    names.ensureCapacity(names.length() + size * 13);
    for (int i = 0; i < size; i++) {
    String organizer = organizers.get(i);
    names.append(organizer);
    names.append(", ");
    }
    names.substring(0, names.length()-1);
    }
    JAVA
    

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90. #DroidconAT
    Optimizing Method invocations
    

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91. #DroidconAT
    Optimizing Much Moar – Method Invocation
    public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    text.setTextColor(attendee.isOrganizer() ?
    getResources().getColor(R.color.accent) :
    getResources().getColor(R.color.black));
    avatar.setImageResource(attendee.getAvatar());
    welcomeText.setText(getString(
    R.string.hello_world, attendee.name));
    }
    JAVA
    

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92. #DroidconAT
    Optimizing Much Moar – Method Invocation
    public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    final Resources res = getResources();
    text.setTextColor(attendee.isOrganizer() ?
    res.getColor(R.color.accent) :
    res.getColor(R.color.black));
    avatar.setImageResource(attendee.getAvatar());
    welcomeText.setText(getString(
    R.string.hello_world, attendee.name));
    }
    JAVA
    

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93. #DroidconAT
    Optimizing Much Moar – Method Invocation
    public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    final Resources res = getResources();
    text.setTextColor(attendee.isOrganizer() ?
    res.getColor(R.color.accent) :
    res.getColor(R.color.black));
    avatar.setImageResource(attendee.getAvatar());
    welcomeText.setText(res.getString(
    R.string.hello_world, attendee.name));
    }
    JAVA
    

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94. #DroidconAT
    Optimizing Access Methods
    

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95. #DroidconAT
    Optimizing Access Methods
    private Attendee attendee;
    public void onViewCreated(View view, Bundle savedInstanceState) {
    button.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
    makeText(getContext(), getWelcomeTextFor(attendee.getName()),
    LENGTH_SHORT).show();
    }
    });
    }
    private String getWelcomeTextFor(String name) {
    return getResources().getString(R.string.welcome_text, name);
    }
    JAVA
    

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96. #DroidconAT
    Finding Access Methods
    https://github.com/JakeWharton/dex-method-list
    $ ./build/dex-method-list src/test/resources/one.apk
    …
    package.DcAtScheduleFragment access$000(DcAtScheduleFragment )
    package.DcAtScheduleFragment access$100(DcAtScheduleFragment , String)
    …
    CL
    

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97. #DroidconAT
    Optimizing Access Methods
    Attendee attendee;
    public void onViewCreated(View view, Bundle savedInstanceState) {
    button.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
    makeText(getContext(), getWelcomeTextFor(attendee.getName()),
    LENGTH_SHORT).show();
    }
    });
    }
    String getWelcomeTextFor(String name) {
    return getResources().getString(R.string.welcome_text, name);
    }
    JAVA
    

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98. Source: https://www.flickr.com/photos/marcus_t_ward/10715983613
    

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99. Source: http://www.bhmpics.com/success_kid-wallpapers.html
    

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100. Source: http://www.flickr.com/photos/21496790@N06/5065834411/
     

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101. #DroidconAT
     www.immobilienscout24.de
     Contact:
     +HasanHosgel
     alosdev
     Thanks for attending!
     We are Hiring! http://www.immobilienscout24.de/jobs
     https://speakerdeck.com/alosdev/perfmatters-for-android-
     droidcon-berlin-2016
     

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102. #DroidconAT
     

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103. #DroidconAT
     

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104. #DroidconAT
     

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106. #DroidconAT
     www.immobilienscout24.de
     Contact:
     +HasanHosgel
     alosdev
     Thanks for attending!
     We are Hiring! http://www.immobilienscout24.de/jobs
     https://speakerdeck.com/alosdev/perfmatters-for-android-
     droidcon-berlin-2016
     

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107. #DroidconAT
     Sources
     • https://ssl.www8.hp.com/ww/en/secure/pdf/4aa5-7696enw.pdf
     • http://www.mobilejoomla.com/media/press/responsive-vs-
     serverside/Responsive-Design-vs-Server-Side-Solutions-
     Infographic.jpg
     • https://speakerdeck.com/jakewharton/eliminating-code-overhead-
     square-hq-2015
     • http://periplanisi.com/android/2013/11/multi-pass-viewgroup-
     and-performance/
     • https://slideshare.net/dougsillars/android-app-performance-
     europe-2015
     • https://www.youtube.com/playlist?list=PLWz5rJ2EKKc9CBxr3BVjPT
     PoDPLdPIFCE
     

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