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Presenting UI with setContentView

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Activity class takes care of creating a window for you in which you can place your UI with setContentView. There are three setContentView methods:

When setContentView is called, this view is placed directly into the activity’s view hierarchy. It can itself be a complex view hierarchy.

Examples

Set content from resource file:

Add resource file (main.xml in this example) with view hierarchy: 

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <TextView android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello" /> 

</FrameLayout>

Set it as content in activity: 

public final class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // The resource will be inflated, 
        // adding all top-level views to the activity.
        setContentView(R.layout.main);
    }
}

Set content to an explicit view: 

public final class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Creating view with container
        final FrameLayout root = new FrameLayout(this);
        final TextView text = new TextView(this);
        text.setText("Hello");
        root.addView(text);

        // Set container as content view
        setContentView(root);
    }
}
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Activity:
* Activity
* Activity launchMode
* Exclude an activity from back-stack history
* Android Activity LifeCycle Explained
* End Application with exclude from Recents
* Presenting UI with setContentView
* Clear your current Activity stack and launch a new Activity
* Up Navigation for Activities
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0 Getting Started
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2 Gradle
3 RecyclerView onClickListeners
4 NavigationView
5 Intent
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163 ExoPlayer
164 Inter-app UI testing with UIAutomator
165 MediaSession
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256 Google Drive API
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258 Annotation Processor
259 SyncAdapter with periodically do sync of data
260 Singleton Class for Toast Message
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262 Android Architecture Components
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264 Play Store
265 Loading Bitmaps Effectively
266 Getting system font names
267 Smartcard
268 Convert vietnamese string to english
269 Contributors