<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
     <application android:label="Test">
 
		...
		...
        <activity android:name=".WriteActivity"></activity>

    </application>

</manifest>		
		
			

			
setContentView(R.layout.view);			
			
			

		
        int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_IMMERSIVE;
        getWindow().getDecorView().setSystemUiVisibility(uiOptions);	
        
        View decorView = getWindow().getDecorView();
        int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                | View.SYSTEM_UI_FLAG_FULLSCREEN
                | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
        decorView.setSystemUiVisibility(uiOptions);        	
		
			

Android API 30

		
        WindowInsetsController controller = getWindow().getDecorView().getWindowInsetsController();
        controller.hide(WindowInsets.Type.statusBars());
        controller.hide(WindowInsets.Type.navigationBars());
        controller.hide(WindowInsets.Type.systemBars());		
		
			

		
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);		
		
			

取消设置

		
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);		
		
			

onCreate 中添加

		
	@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.settings_activity);

        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
	}
		
			

Activity 中添加

		
 	@Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
            default:
                break;
        }
        return super.onOptionsItemSelected(item);
    }

		
			

在AndroidManifest.xml中标明Activity的主题

		
<activity
            android:name=".ui.ShareActivity"
            android:exported="false"
            android:theme="@style/AppTheme"/>		
		
			

values/styles.xml 文件中增加

		
 	<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorThemeBackGround</item>
        <item name="colorPrimaryDark">@color/colorThemeBackGround</item>
        <item name="colorAccent">@color/colorThemeBackGround</item>
    </style>