Launch Screens: From a Tap to Your App

The launch screen is a user’s first experience of your application and, hence, should be designed with great care. In this talk, we will deep dive into the concept of launch screen, discover how to measure, debug & optimise them efficiently, and learn more about how to implement them correctly. In other words, this talk is all about discussing for ±45 min about screens displayed less than 5 seconds.

Transcript

1. @cyrilmottier
   Launch screens
   From a Tap to your App
   

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2. 38
   sec
   average
   interaction time
   

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3. 23
   %
   apps used
   only once
   38
   sec
   average
   interaction time
   

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4. 13
   launches per
   month
   23
   %
   apps used
   only once
   38
   sec
   average
   interaction time
   Source: Mobile Life Research Centre, University of Stockholm & Localytics
   

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5. Polish your
   launching experience
   

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6. View Slide

7. Placeholder UI
   /ˈpleɪshəʊldə(r) juː-aɪ/
   Display core structural elements (status bar, app bar, etc.) without
   content until the app has loaded.
   

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8. Branded launch
   /ˈbrændɪd lɔːntʃ/
   Display your logo or other elements that improve brand recognition to
   portray a brand while the app is loading.
   

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9. Branded launch
   Google Maps
   Placeholder UI
   Settings
   

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10. Branded launch
    Google Maps
    Placeholder UI
    Settings
    your side
    Choose
    

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11. Branded launch
    Google Maps
    Placeholder UI
    Settings
    

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12. Yes!
    A launch screen is intentionally boring
    

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13. Source: iOS Human Interface Guidelines, Apple
    If you think that following these guidelines will
    result in a plain, boring launch image, you’re right.
    Remember, the launch image doesn’t provide you
    with an opportunity for artistic expression. It’s
    solely intended to enhance the user’s perception of
    your app as quick to launch and immediately
    ready for use.
    “
    

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14. Timeline of a launch
    

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15. Timeline of a launch
    Slowed down version
    

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16. User taps
    on icon
    Timeline of a launch
    1 2 3 4 5
    

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17. User taps
    on icon
    Timeline of a launch
    1 2
    Fit to screen
    animation starts
    3 4 5
    

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18. User taps
    on icon
    Timeline of a launch
    1 2
    Fit to screen
    animation starts
    3 4 5
    Fit to screen
    animation ends
    

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19. User taps
    on icon
    Timeline of a launch
    1 2
    Fit to screen
    animation starts
    3 4 5
    Fit to screen
    animation ends
    Window
    switching starts
    

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20. User taps
    on icon
    Timeline of a launch
    1 2
    Fit to screen
    animation starts
    3 4 5
    Fit to screen
    animation ends
    Window
    switching starts
    App content
    finishes loading
    

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21. User taps
    on icon
    Timeline of a launch
    1 2
    Fit to screen
    animation starts
    3 4 5
    Fit to screen
    animation ends
    Window
    switching starts
    App content
    finishes loading
    

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22. 1 2 3 4 5
    Launcher & Intent triggering
    Entering animation
    Static launch screen
    Content switching / fading
    Application fully drawn
    1
    2
    3
    4
    5
    

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23. 1 2 3 5
    System App
    Launcher & Intent triggering
    Entering animation
    Static launch screen
    Content switching / fading
    Application fully drawn
    1
    2
    3
    4
    5
    4
    

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24. 5
    The perfect launch
    1 2
    3
    4
    

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25. 1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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26. 1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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27. System
    1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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28. System
    App
    1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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29. System
    App
    Cold start
    1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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30. System
    App
    Warm start
    1 Load and launch the app
    2 Display a starting/preview window
    3 Create the app process
    4 Create the app object
    5 Launch the main thread
    6 Create the main activity
    7 Inflate views
    8 Lay out the screen
    9 Perform the initial draw
    

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31. PhoneWindowManager.java
    Context context = mContext;
    try {
    context = context.createPackageContext(packageName, 0);
    context.setTheme(theme);
    } catch (PackageManager.NameNotFoundException e) {
    // Ignore
    }
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    

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32. PhoneWindowManager.java
    Context context = mContext;
    try {
    context = context.createPackageContext(packageName, 0);
    context.setTheme(theme);
    } catch (PackageManager.NameNotFoundException e) {
    // Ignore
    }
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    Create Context for the
    started application
    context = context.createPackageContext(packageName, 0);
    

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33. PhoneWindowManager.java
    Context context = mContext;
    try {
    context = context.createPackageContext(packageName, 0);
    context.setTheme(theme);
    } catch (PackageManager.NameNotFoundException e) {
    // Ignore
    }
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    Set the target theme
    context.setTheme(theme);
    

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34. PhoneWindowManager.java
    Context context = mContext;
    try {
    context = context.createPackageContext(packageName, 0);
    context.setTheme(theme);
    } catch (PackageManager.NameNotFoundException e) {
    // Ignore
    }
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    Create new Window
    and set it up
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    

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35. PhoneWindowManager.java
    Context context = mContext;
    try {
    context = context.createPackageContext(packageName, 0);
    context.setTheme(theme);
    } catch (PackageManager.NameNotFoundException e) {
    // Ignore
    }
    final PhoneWindow win = new PhoneWindow(context);
    win.setType(WindowManager.LayoutParams.TYPE_APPLICATION_STARTING);
    win.setFlags(/*...*/);
    final WindowManager.LayoutParams params = win.getAttributes();
    // Tweak params
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).
    addView(win.getDecorView(), params);
    Display the newly
    created Window
    

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36. Same look,
    different process
    …and that explains a lot
    

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37. $ adb logcat | grep “ActivityManager”
    ActivityManager: Displayed com.launchtime/.LaunchTimeActivity: +666ms
    API 19+
    

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39. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    reportFullyDrawn();

    }

    // ...
    }
    

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40. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    reportFullyDrawn();

    }

    // ...
    }
    reportFullyDrawn();
    

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41. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    reportFullyDrawn();

    }

    // ...
    }
    SecurityException
    on KitKat…
    reportFullyDrawn();
    

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42. public final class ActivityCompatAdditions {

    

    private static final Impl IMPL;

    

    static {

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {

    IMPL = new LollipopImpl();

    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {

    IMPL = new KitKatImpl();

    } else {

    IMPL = new BaseImpl();

    }

    }

    

    private ActivityCompatAdditions() {

    // No instances

    } 

    

    public static void reportFullyDrawn(Activity activity) {

    IMPL.reportFullyDrawn(activity);

    } 

    

    private interface Impl {

    void reportFullyDrawn(Activity activity);

    } 

    

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43. private static final class BaseImpl implements Impl {

    @Override

    public void reportFullyDrawn(Activity activity) {

    // No-op

    }

    }

    

    private static final class KitKatImpl implements Impl {

    @Override @TargetApi(Build.VERSION_CODES.KITKAT)

    public void reportFullyDrawn(Activity activity) {

    try {

    activity.reportFullyDrawn();

    } catch (SecurityException se) {

    // Prevent an Exception on KitKat

    }

    }

    }

    

    private static final class LollipopImpl implements Impl {

    @Override @TargetApi(Build.VERSION_CODES.KITKAT)

    public void reportFullyDrawn(Activity activity) {

    activity.reportFullyDrawn();

    }

    }

    

    }
    

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44. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    

    }

    // ...
    }
    reportFullyDrawn();
    

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45. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    

    }

    // ...
    }
    reportFullyDrawn();
    

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46. public class LaunchTimeActivity extends AppCompatActivity
    implements LoaderManager.LoaderCallbacks {

    

    private static final int LOADER_YO = 0xcafe;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_launch_time);
    

    getSupportLoaderManager().initLoader(LOADER_YO, null, this);

    }

    

    @Override

    public void onLoadFinished(Loader loader, Void data) {

    switch (loader.getId()) {

    case LOADER_YO:

    // ...

    break;

    }

    }

    // ...
    }
    ActivityCompatAdditions.reportFullyDrawn(this);
    

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47. $ adb logcat | grep “ActivityManager”
    ActivityManager: Displayed com.launchtime/.LaunchTimeActivity: +666ms
    ActivityManager: Fully drawn com.launchtime/.LaunchTimeActivity: +1s440ms
    API 19+
    

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48. com.launchtime/.LaunchScreenActivity
    $ adb shell am start
    

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49. com.launchtime/.LaunchScreenActivity
    $ adb shell am start -W
    

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50. View Slide

51. View Slide

52. $ adb shell am start -W com.launchtime/.LaunchScreenActivity
    Starting: Intent { act=android.intent.action.MAIN
    cat=[android.intent.category.LAUNCHER]
    cmp=com.launchtime/.LaunchScreenActivity }
    Status: ok
    Activity: com.launchtime/.LaunchScreenActivity
    ThisTime: 2426
    TotalTime: 2426
    WaitTime: 2488
    Complete
    

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53. $ adb shell screenrecord /sdcard/launch.mp4
    API 19+
    

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54. $ adb shell screenrecord /sdcard/launch.mp4
    --bugreport
    API 21+
    

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55. API 21+
    

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56. API 21+
    

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57. View Slide

58. 11:16:46.666 f=26 (0)
    

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59. 11:16:46.666 f=26 (0)
    11:16:46.666
    Frame timestamp
    

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60. 11:16:46.666 f=26 (0)
    f=26
    Frame number
    

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61. 11:16:46.666 f=26 (0)
    (0)
    Dropped frames
    count
    

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62. 11:16:46.666 f=26 (0)
    Frame timestamp
    Dropped frames
    count
    Frame number
    

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63. SystemClock.sleep(2000L)
    all the things \o/
    in debug only…
    

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64. SystemClock.sleep(2000L)
    all the things \o/
    in debug only…
    

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65. com.launchtime/.LaunchScreenActivity
    $ adb shell am start
    

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66. com.launchtime/.LaunchScreenActivity
    $ adb shell am start -S
    

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67. View Slide

68. View Slide

69. Developer options
    Background process limit
    

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70. Developer options
    Background process limit
    

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71. Force cold launch
    with “No background processes”
    

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72. Measure, measure
    and measure again!
    

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73. Use
    Systrace & Traceview
    extensively
    

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74. Lazy-load & async
    all the things
    

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75. In general, beware of
    static init & onCreate
    

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76. public class LazyProvider extends ContentProvider {

    

    private static final int MODEL = 101;

    private static final int MODEL_ID = 102;

    

    private static final UriMatcher URI_MATCHER;

    static {

    URI_MATCHER = new UriMatcher(UriMatcher.NO_MATCH);

    URI_MATCHER.addURI(LazyContract.AUTHORITY, "/model", MODEL);

    URI_MATCHER.addURI(LazyContract.AUTHORITY, "/model/#", MODEL_ID);

    // ...

    }

    

    private SQLiteOpenHelper mOpenHelper;

    

    @Override

    public boolean onCreate() {

    mOpenHelper = new LoadOpenHelper(getContext());

    return true;

    }

    // ...

    }
    LazyProvider.java
    

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77. public class LazyProvider extends ContentProvider {

    

    private static final int MODEL = 101;

    private static final int MODEL_ID = 102;

    

    private static final UriMatcher URI_MATCHER;

    static {

    URI_MATCHER = new UriMatcher(UriMatcher.NO_MATCH);

    URI_MATCHER.addURI(LazyContract.AUTHORITY, "/model", MODEL);

    URI_MATCHER.addURI(LazyContract.AUTHORITY, "/model/#", MODEL_ID);

    // ...

    }

    

    private SQLiteOpenHelper mOpenHelper;

    

    @Override

    public boolean onCreate() {

    mOpenHelper = new LoadOpenHelper(getContext());

    return true;

    }

    // ...

    }
    LazyProvider.java
    private static final UriMatcher URI_MATCHER;
    Created at class loading
    but used only in CRUD…
    

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78. public abstract class LazyGetter {

    

    private final AtomicReference> mCachedValue =
    new AtomicReference<>(Optional.empty());

    

    public final T get() {

    Optional value = mCachedValue.get();

    if (!value.isPresent()) {

    synchronized (mCachedValue) {

    value = mCachedValue.get();

    if (!value.isPresent()) {

    mCachedValue.set(Optional.ofNullable(initialValue()));

    }

    }

    }

    return mCachedValue.get().get();

    }

    

    protected abstract T initialValue();

    

    }
    LazyGetter.java
    

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79. public class LazyProvider extends ContentProvider {

    

    private static final int MODEL = 101;

    private static final int MODEL_ID = 102;

    

    private static final LazyGetter URI_MATCHER =
    new LazyGetter() {

    @Override

    protected UriMatcher initialValue() {

    final UriMatcher uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);

    uriMatcher.addURI(LazyContract.AUTHORITY, "/model", MODEL);

    uriMatcher.addURI(LazyContract.AUTHORITY, "/model/#", MODEL_ID);

    // ...

    return uriMatcher;

    }

    };
    

    // ...

    }
    LazyProvider.java
    

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80. android:windowDisablePreview
    the (wrong) simple way…
    

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81. 

    xmlns:android="http://schemas.android.com/apk/res/android">

    

    android:icon="@mipmap/ic_launcher"

    android:label="@string/app_name"

    android:theme="@style/Theme.LaunchTime">

    

    android:name=".LaunchScreenActivity">

    

    

    

    

    

    

    

    

    
    AndroidManifest.xml
    

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82. 

    xmlns:android="http://schemas.android.com/apk/res/android">

    

    android:icon="@mipmap/ic_launcher"

    android:label="@string/app_name"

    android:theme="@style/Theme.LaunchTime">

    

    android:name=".LaunchScreenActivity">

    

    

    

    

    

    

    

    

    
    Default theme applies
    to all Activities
    AndroidManifest.xml
    android:theme="@style/Theme.LaunchTime">
    

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83. 
    

    

    
<br/><item name="android:colorPrimary">@color/colorPrimary</item>
<br/><item name="android:colorPrimaryDark">@color/colorPrimaryDark</item>
<br/><item name="android:colorAccent">@color/colorAccent</item>
<br/><item name="android:windowBackground">@color/appBackground</item>
<br/>

    

    

    values/themes.xml
    

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84. No project on Earth is
    minSdk 21+ except
    Android built-in apps!
    

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85. to the rescue…
    AppCompat
    

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86. to the rescue…
    AppCompat
    (almost)
    

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87. to the rescue…
    AppCompat
    (almost)
    

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88. UI design is all about
    

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89. mirrors
    UI design is all about
    &mirrors
    mirrors
    &
    smoke
    

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90. Switch between
    compile time & runtime
    themes
    

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91. 

    

    

    

    

    
    values/attrs.xml
    

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92. 

    

    

    name=“PreviewTheme.LaunchTime"
    parent=“android:Theme.Holo.Light.DarkActionBar">
    

    
    @dimen/abc_action_bar_default_height_material
    

    @style/PreviewWidget.ActionBar
    @color/appBackground
    @style/Theme.LaunchTime
    

    

    

    
    values/themes_preview.xml
    

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93. 

    

    

    name=“PreviewTheme.LaunchTime"
    parent=“android:Theme.Holo.Light.DarkActionBar">
    

    
    @dimen/abc_action_bar_default_height_material
    

    @style/PreviewWidget.ActionBar
    @color/appBackground
    @style/Theme.LaunchTime
    

    

    

    
    values/themes_preview.xml
    
    @dimen/abc_action_bar_default_height_material
    
    Force pre-Lollipop
    ActionBars height
    to 48 / 56 / 64dp
    

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94. 

    

    

    name=“PreviewTheme.LaunchTime"
    parent=“android:Theme.Holo.Light.DarkActionBar">
    

    
    @dimen/abc_action_bar_default_height_material
    

    @style/PreviewWidget.ActionBar
    @color/appBackground
    @style/Theme.LaunchTime
    

    

    

    
    values/themes_preview.xml
    @style/Theme.LaunchTime
    Define the theme
    to use at runtime
    

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95. 

    

    

    name="PreviewWidget.ActionBar"
    parent=“android:Widget.Holo.Light.ActionBar.Solid.Inverse">
    

    @color/colorPrimary

    showTitle
    

    

    

    
    values/styles_preview.xml
    

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96. 

    

    

    name="PreviewTheme.LaunchTime"
    parent=“android:Theme.Material.Light.DarkActionBar">
    

    @color/colorPrimary

    @color/colorPrimaryDark

    @color/colorAccent

    @color/appBackground

    @style/Theme.LaunchTime
    

    

    

    
    values-v21/themes_preview.xml
    

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97. 

    

    

    name="PreviewTheme.LaunchTime"
    parent=“android:Theme.Material.Light.DarkActionBar">
    

    @color/colorPrimary

    @color/colorPrimaryDark

    @color/colorAccent

    @color/appBackground

    @style/Theme.LaunchTime
    

    

    

    
    values-v21/themes_preview.xml
    parent=“android:Theme.Material.Light.DarkActionBar"
    Use Theme.Material
    on v-21+ devices
    

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98. 

    

    

    name="PreviewTheme.LaunchTime"
    parent=“android:Theme.Material.Light.DarkActionBar">
    

    @color/colorPrimary

    @color/colorPrimaryDark

    @color/colorAccent

    @color/appBackground

    @style/Theme.LaunchTime
    

    

    

    
    values-v21/themes_preview.xml
    Define the theme
    to use at runtime
    @style/Theme.LaunchTime
    

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99. 

    xmlns:android="http://schemas.android.com/apk/res/android">

    

    android:icon="@mipmap/ic_launcher"

    android:label="@string/app_name"

    android:theme="@style/PreviewTheme.LaunchTime">

    

    

    

    

    

    

    

    

    

    

    
    AndroidManifest.xml
    

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100. 

     xmlns:android="http://schemas.android.com/apk/res/android">

     

     android:icon="@mipmap/ic_launcher"

     android:label="@string/app_name"

     android:theme="@style/PreviewTheme.LaunchTime">

     

     

     

     

     

     

     

     

     

     

     
     AndroidManifest.xml
     android:theme="@style/PreviewTheme.LaunchTime"
     Tell the system to use a
     temporary preview theme
     

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101. public final class ThemeUtils {
     private ThemeUtils() {
     // No instances
     }
     @UiThread
     public static void ensureRuntimeTheme(Context context) {
     final TypedValue tv = new TypedValue();
     context.getTheme().resolveAttribute(R.attr.ltRuntimeTheme, tv, true);
     if (tv.resourceId <= 0) {
     throw new IllegalArgumentException("ltRuntimeTheme " +
     "not defined in the preview theme");
     }
     context.setTheme(tv.resourceId);
     }
     }
     ThemeUtils.java
     

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102. public class LaunchScreenActivity extends AppCompatActivity {

     

     @Override

     protected void onCreate(Bundle savedInstanceState) {

     ThemeUtils.ensureRuntimeTheme(this);

     super.onCreate(savedInstanceState);
     

     setContentView(R.layout.activity_launch_screen);

     // ...

     }

     

     }
     LaunchScreenActivity.java
     

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103. public class LaunchScreenActivity extends AppCompatActivity {

     

     @Override

     protected void onCreate(Bundle savedInstanceState) {

     ThemeUtils.ensureRuntimeTheme(this);

     super.onCreate(savedInstanceState);
     

     setContentView(R.layout.activity_launch_screen);

     // ...

     }

     

     }
     LaunchScreenActivity.java
     Inherit AppCompatActivity
     to get AppCompat behaviour
     public class LaunchScreenActivity extends AppCompatActivity {
     

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104. public class LaunchScreenActivity extends AppCompatActivity {

     

     @Override

     protected void onCreate(Bundle savedInstanceState) {

     ThemeUtils.ensureRuntimeTheme(this);

     super.onCreate(savedInstanceState);
     

     setContentView(R.layout.activity_launch_screen);

     // ...

     }

     

     }
     LaunchScreenActivity.java
     ThemeUtils.ensureRuntimeTheme(this); Dynamically switch
     to the runtime theme
     

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105. Don’t forget every screen is an
     entry point
     

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106. Consider launch screen as
     boring screen
     

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107. Don’t try to outsmart Android
     Embrace it!
     

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108. That’s all Folks!
     @cyrilmottier • cyrilmottier.com
     

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