Photo Picker Dialog: Use sandboxed utility process for decoding images.

chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java

Index: chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
index 6c73972eadb3c87da1d3b42c7a18259e2ac6809e..9ed19c9448c644d4709ae6189320f179331f6070 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerCategoryView.java
@@ -20,6 +20,7 @@ import org.chromium.chrome.browser.widget.selection.SelectableListLayout;
 import org.chromium.chrome.browser.widget.selection.SelectionDelegate;
 import org.chromium.ui.PhotoPickerListener;
 
+import java.util.Arrays;
 import java.util.List;
 
 /**
@@ -27,7 +28,8 @@ import java.util.List;
  * the photo picker, for example the RecyclerView and the bitmap caches.
  */
 public class PickerCategoryView extends RelativeLayout
-        implements FileEnumWorkerTask.FilesEnumeratedCallback, OnMenuItemClickListener {
+        implements FileEnumWorkerTask.FilesEnumeratedCallback, RecyclerView.RecyclerListener,
+                   DecoderServiceHost.ServiceReadyCallback, OnMenuItemClickListener {
     // The dialog that owns us.
     private PhotoPickerDialog mDialog;
 
@@ -46,6 +48,9 @@ public class PickerCategoryView extends RelativeLayout
     // The callback to notify the listener of decisions reached in the picker.
     private PhotoPickerListener mListener;
 
+    // The host class for the decoding service.
+    private DecoderServiceHost mDecoderServiceHost;
+
     // The RecyclerView showing the images.
     private RecyclerView mRecyclerView;
 
@@ -71,6 +76,9 @@ public class PickerCategoryView extends RelativeLayout
     // A worker task for asynchronously enumerating files off the main thread.
     private FileEnumWorkerTask mWorkerTask;
 
+    // Whether the connection to the service has been established.
+    private boolean mServiceReady;
+
     public PickerCategoryView(Context context) {
         super(context);
         postConstruction(context);
@@ -84,6 +92,11 @@ public class PickerCategoryView extends RelativeLayout
     private void postConstruction(Context context) {
         mContext = context;
 
+        mDecoderServiceHost = new DecoderServiceHost(this);
+        mDecoderServiceHost.bind(mContext);
+
+        enumerateBitmaps();
+
         mSelectionDelegate = new SelectionDelegate<PickerBitmap>();
 
         View root = LayoutInflater.from(context).inflate(R.layout.photo_picker_dialog, this);
@@ -107,18 +120,21 @@ public class PickerCategoryView extends RelativeLayout
         mRecyclerView.addItemDecoration(new GridSpacingItemDecoration(mColumns, mPadding));
 
         // TODO(finnur): Implement caching.
-        // TODO(finnur): Remove this once the decoder service is in place.
-        prepareBitmaps();
     }
 
     /**
-     * Cancels any outstanding requests.
+     * Severs the connection to the decoding utility process and cancels any outstanding requests.
      */
     public void onDialogDismissed() {
         if (mWorkerTask != null) {
             mWorkerTask.cancel(true);
             mWorkerTask = null;
         }
+
+        if (mDecoderServiceHost != null) {
+            mDecoderServiceHost.unbind(mContext);
+            mDecoderServiceHost = null;
+        }
     }
 
     /**
@@ -141,8 +157,25 @@ public class PickerCategoryView extends RelativeLayout
     @Override
     public void filesEnumeratedCallback(List<PickerBitmap> files) {
         mPickerBitmaps = files;
-        if (files != null && files.size() > 0) {
-            mPickerAdapter.notifyDataSetChanged();
+        processBitmaps();
+    }
+
+    // DecoderServiceHost.ServiceReadyCallback:
+
+    @Override
+    public void serviceReady() {
+        mServiceReady = true;
+        processBitmaps();
+    }
+
+    // RecyclerView.RecyclerListener:
+
+    @Override
+    public void onViewRecycled(RecyclerView.ViewHolder holder) {
+        PickerBitmapViewHolder bitmapHolder = (PickerBitmapViewHolder) holder;
+        String filePath = bitmapHolder.getFilePath();
+        if (filePath != null) {
+            getDecoderServiceHost().cancelDecodeImage(filePath);
         }
     }
 
@@ -162,6 +195,16 @@ public class PickerCategoryView extends RelativeLayout
         return false;
     }
 
+    /**
+     * Start loading of bitmaps, once files have been enumerated and service is
+     * ready to decode.
+     */
+    private void processBitmaps() {
+        if (mServiceReady && mPickerBitmaps != null) {
+            mPickerAdapter.notifyDataSetChanged();
+        }
+    }
+
     // Simple accessors:
 
     public int getImageSize() {
@@ -176,6 +219,10 @@ public class PickerCategoryView extends RelativeLayout
         return mPickerBitmaps;
     }
 
+    public DecoderServiceHost getDecoderServiceHost() {
+        return mDecoderServiceHost;
+    }
+
     public boolean isMultiSelectAllowed() {
         return mMultiSelectionAllowed;
     }
@@ -212,14 +259,15 @@ public class PickerCategoryView extends RelativeLayout
     }
 
     /**
-     * Prepares bitmaps for loading.
+     * Asynchronously enumerates bitmaps on disk.
      */
-    private void prepareBitmaps() {
+    private void enumerateBitmaps() {
         if (mWorkerTask != null) {
             mWorkerTask.cancel(true);
         }
 
-        mWorkerTask = new FileEnumWorkerTask(this, new MimeTypeFileFilter("image/*"));
+        mWorkerTask =
+                new FileEnumWorkerTask(this, new MimeTypeFileFilter(Arrays.asList("image/*")));
         mWorkerTask.execute();
     }