+ fullScreenVideoFrameLayout = (FrameLayout) findViewById(R.id.full_screen_video_framelayout);
+
+ // Create a double-tap listener to toggle full-screen mode.
+ final GestureDetector gestureDetector = new GestureDetector(this, new GestureDetector.SimpleOnGestureListener() {
+ // Override `onDoubleTap()`. All other events are handled using the default settings.
+ @Override
+ public boolean onDoubleTap(MotionEvent event) {
+ if (fullScreenBrowsingModeEnabled) { // Only process the double-tap if full screen browsing mode is enabled.
+ // Toggle `inFullScreenBrowsingMode`.
+ inFullScreenBrowsingMode = !inFullScreenBrowsingMode;
+
+ if (inFullScreenBrowsingMode) { // Switch to full screen mode.
+ // Hide the `appBar`.
+ appBar.hide();
+
+ // Hide the `BannerAd` in the free flavor.
+ if (BuildConfig.FLAVOR.contentEquals("free")) {
+ BannerAd.hideAd(adView);
+ }
+
+ // Modify the system bars.
+ if (hideSystemBarsOnFullscreen) { // Hide everything.
+ // Remove the translucent overlays.
+ getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
+
+ // Remove the translucent status bar overlay on the `Drawer Layout`, which is special and needs its own command.
+ drawerLayout.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
+
+ /* SYSTEM_UI_FLAG_FULLSCREEN hides the status bar at the top of the screen.
+ * SYSTEM_UI_FLAG_HIDE_NAVIGATION hides the navigation bar on the bottom or right of the screen.
+ * SYSTEM_UI_FLAG_IMMERSIVE_STICKY makes the status and navigation bars translucent and automatically rehides them after they are shown.
+ */
+ rootCoordinatorLayout.setSystemUiVisibility(View.SYSTEM_UI_FLAG_FULLSCREEN | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
+
+ // Set `rootCoordinatorLayout` to fill the whole screen.
+ rootCoordinatorLayout.setFitsSystemWindows(false);
+ } else { // Hide everything except the status and navigation bars.
+ // Set `rootCoordinatorLayout` to fit under the status and navigation bars.
+ rootCoordinatorLayout.setFitsSystemWindows(false);
+
+ if (translucentNavigationBarOnFullscreen) { // There is an Android Support Library bug that causes a scrim to print on the right side of the `Drawer Layout` when the navigation bar is displayed on the right of the screen.
+ // Set the navigation bar to be translucent.
+ getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
+ }
+ }
+ } else { // Switch to normal viewing mode.
+ // Show the `appBar`.
+ appBar.show();
+
+ // Show the `BannerAd` in the free flavor.
+ if (BuildConfig.FLAVOR.contentEquals("free")) {
+ // Reload the ad. Because the screen may have rotated, we need to use `reloadAfterRotate`.
+ BannerAd.reloadAfterRotate(adView, getApplicationContext(), getString(R.string.ad_id));
+
+ // Reinitialize the `adView` variable, as the `View` will have been removed and re-added by `BannerAd.reloadAfterRotate()`.
+ adView = findViewById(R.id.adView);
+ }
+
+ // Remove the translucent navigation bar flag if it is set.
+ getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
+
+ // Add the translucent status flag if it is unset. This also resets `drawerLayout's` `View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN`.
+ getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
+
+ // Remove any `SYSTEM_UI` flags from `rootCoordinatorLayout`.
+ rootCoordinatorLayout.setSystemUiVisibility(0);
+
+ // Constrain `rootCoordinatorLayout` inside the status and navigation bars.
+ rootCoordinatorLayout.setFitsSystemWindows(true);
+ }
+
+ // Consume the double-tap.
+ return true;
+ } else { // Do not consume the double-tap because full screen browsing mode is disabled.
+ return false;
+ }
+ }
+ });
+
+ // Pass all touch events on `mainWebView` through `gestureDetector` to check for double-taps.
+ mainWebView.setOnTouchListener(new View.OnTouchListener() {
+ @Override
+ public boolean onTouch(View v, MotionEvent event) {
+ // Send the `event` to `gestureDetector`.
+ return gestureDetector.onTouchEvent(event);
+ }
+ });