Merge pull request #587 from owncloud/improved_fullscreen_for_gallery

Improved full screen in gallery of images

src/com/owncloud/android/ui/preview/PreviewImageActivity.java

@@ -16,6 +16,7 @@
  */
 package com.owncloud.android.ui.preview;
 
+import android.annotation.SuppressLint;
 import android.content.BroadcastReceiver;
 import android.content.ComponentName;
 import android.content.Context;
@@ -23,10 +24,14 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.ServiceConnection;
 import android.content.SharedPreferences;
+import android.os.Build;
 import android.os.Bundle;
+import android.os.Handler;
 import android.os.IBinder;
+import android.os.Message;
 import android.preference.PreferenceManager;
 import android.support.v4.view.ViewPager;
+import android.view.View;
 
 import com.actionbarsherlock.app.ActionBar;
 import com.actionbarsherlock.view.MenuItem;
@@ -70,15 +75,17 @@ ViewPager.OnPageChangeListener, OnRemoteOperationListener {
     
     public static final String KEY_WAITING_TO_PREVIEW = "WAITING_TO_PREVIEW";
     private static final String KEY_WAITING_FOR_BINDER = "WAITING_FOR_BINDER";
-    
+
+    private static final int INITIAL_HIDE_DELAY = 0; // immediate hide
+
     private ExtendedViewPager mViewPager;
     private PreviewImagePagerAdapter mPreviewImagePagerAdapter;    
     
     private boolean mRequestWaitingForBinder;
     
     private DownloadFinishReceiver mDownloadFinishReceiver;
-
-    private boolean mFullScreen;
+    
+    private View mFullScreenAnchorView;
     
     
     @Override
@@ -96,9 +103,31 @@ ViewPager.OnPageChangeListener, OnRemoteOperationListener {
         // PIN CODE request
         if (getIntent().getExtras() != null && savedInstanceState == null && fromNotification()) {
             requestPinCode();
-        }         
+        }
+
+        // Make sure we're running on Honeycomb or higher to use FullScreen and
+        // Immersive Mode
+        if (isHoneycombOrHigher()) {
         
-        mFullScreen = true;
+            mFullScreenAnchorView = getWindow().getDecorView();
+            // to keep our UI controls visibility in line with system bars
+            // visibility
+            mFullScreenAnchorView.setOnSystemUiVisibilityChangeListener(new View.OnSystemUiVisibilityChangeListener() {
+                @SuppressLint("InlinedApi")
+                @Override
+                public void onSystemUiVisibilityChange(int flags) {
+                    boolean visible = (flags & View.SYSTEM_UI_FLAG_HIDE_NAVIGATION) == 0;
+                    ActionBar actionBar = getSupportActionBar();
+                    if (visible) {
+                        actionBar.show();
+                    } else {
+                        actionBar.hide();
+                    }
+                }
+            });
+
+        }
+            
         if (savedInstanceState != null) {
             mRequestWaitingForBinder = savedInstanceState.getBoolean(KEY_WAITING_FOR_BINDER);
         } else {
@@ -129,6 +158,46 @@ ViewPager.OnPageChangeListener, OnRemoteOperationListener {
     }
     
     
+    protected void onPostCreate(Bundle savedInstanceState)  {
+        super.onPostCreate(savedInstanceState);
+        
+        // Trigger the initial hide() shortly after the activity has been 
+        // created, to briefly hint to the user that UI controls 
+        // are available
+        delayedHide(INITIAL_HIDE_DELAY);
+        
+    }
+    
+    Handler mHideSystemUiHandler = new Handler() {
+        @Override
+        public void handleMessage(Message msg) {
+            if (isHoneycombOrHigher()) {
+                hideSystemUI(mFullScreenAnchorView);
+            }
+            getSupportActionBar().hide();
+        }
+    };
+    
+    private void delayedHide(int delayMillis)   {
+        mHideSystemUiHandler.removeMessages(0);
+        mHideSystemUiHandler.sendEmptyMessageDelayed(0, delayMillis);
+    }
+    
+    
+    /// handle Window Focus changes
+    @Override
+    public void onWindowFocusChanged(boolean hasFocus) {
+        super.onWindowFocusChanged(hasFocus);
+        
+        // When the window loses focus (e.g. the action overflow is shown),
+        // cancel any pending hide action.
+        if (!hasFocus) {
+            mHideSystemUiHandler.removeMessages(0);
+        }
+    }
+    
+    
+    
     @Override
     public void onStart() {
         super.onStart();
@@ -390,16 +459,36 @@ ViewPager.OnPageChangeListener, OnRemoteOperationListener {
 
     }
 
-    public void toggleFullScreen() {
-        ActionBar actionBar = getSupportActionBar();
-        if (mFullScreen) {
-            actionBar.show();
-            
+    @SuppressLint("InlinedApi")
+	public void toggleFullScreen() {
+
+        if (isHoneycombOrHigher()) {
+        
+            boolean visible = (mFullScreenAnchorView.getSystemUiVisibility()
+                    & View.SYSTEM_UI_FLAG_HIDE_NAVIGATION) == 0;
+
+            if (visible) {
+                hideSystemUI(mFullScreenAnchorView);
+                // actionBar.hide(); // propagated through
+                // OnSystemUiVisibilityChangeListener()
+            } else {
+                showSystemUI(mFullScreenAnchorView);
+                // actionBar.show(); // propagated through
+                // OnSystemUiVisibilityChangeListener()
+            }
+
         } else {
-            actionBar.hide();
-            
+
+            ActionBar actionBar = getSupportActionBar();
+            if (!actionBar.isShowing()) {
+                actionBar.show();
+
+            } else {
+                actionBar.hide();
+
+            }
+
         }
-        mFullScreen = !mFullScreen;
     }
 
     @Override
@@ -460,5 +549,39 @@ ViewPager.OnPageChangeListener, OnRemoteOperationListener {
         // TODO Auto-generated method stub
         
     }
+    
+    
+    @SuppressLint("InlinedApi")
+	private void hideSystemUI(View anchorView) {
+        anchorView.setSystemUiVisibility(
+                View.SYSTEM_UI_FLAG_HIDE_NAVIGATION         // hides NAVIGATION BAR; Android >= 4.0
+            |   View.SYSTEM_UI_FLAG_FULLSCREEN              // hides STATUS BAR;     Android >= 4.1
+            |   View.SYSTEM_UI_FLAG_IMMERSIVE               // stays interactive;    Android >= 4.4
+            |   View.SYSTEM_UI_FLAG_LAYOUT_STABLE           // draw full window;     Android >= 4.1
+            |   View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN       // draw full window;     Android >= 4.1
+            |   View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION  // draw full window;     Android >= 4.1
+        );
+    }
+    
+    @SuppressLint("InlinedApi")
+    private void showSystemUI(View anchorView) {
+        anchorView.setSystemUiVisibility(
+                View.SYSTEM_UI_FLAG_LAYOUT_STABLE           // draw full window;     Android >= 4.1
+            |   View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN       // draw full window;     Android >= 4.1
+            |   View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION  // draw full window;     Android >= 4.1
+        );
+    }
+
+    /**
+     * Checks if OS version is Honeycomb one or higher
+     * 
+     * @return boolean
+     */
+    private boolean isHoneycombOrHigher() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
+            return true;
+        }
+        return false;
+    }
 
 }