JB43R11 Save for offline readings

MENU>Save for offline readingをクリックすると以下の処理を通る。

１：packages/apps/Browser/src/com/android/browser/Controller.java

   1741         @Override
   1742         protected Long doInBackground(Void... params) {
   1743             if (!mTab.saveViewState(mValues)) {
                                                ＝＞　snapshot.tab経由　＝＞２へ
   1744                 return null;
   1745             }
   1746             if (isCancelled()) {
   1747                 String path = mValues.getAsString(Snapshots.VIEWSTATE_PATH);
   1748                 File file = mActivity.getFileStreamPath(path);
   1749                 if (!file.delete()) {
   1750                     file.deleteOnExit();
   1751                 }
   1752                 return null;
   1753             }
   1754             final ContentResolver cr = mActivity.getContentResolver();
   1755             Uri result = cr.insert(Snapshots.CONTENT_URI, mValues);
   1756             if (result == null) {
   1757                 return null;
   1758             }
   1759             long id = ContentUris.parseId(result);
   1760             return id;
   1761         }

２：packages/apps/Browser/src/com/android/browser/Tab.java

   1842     /**
   1843      * Probably want to call this on a background thread
   1844      */
   1845     public boolean saveViewState(ContentValues values) {
   1846         WebViewClassic web = getWebViewClassic();
   1847         if (web == null) return false;
   1848         String path = UUID.randomUUID().toString();
   1849         SaveCallback callback = new SaveCallback();
   1850         OutputStream outs = null;
   1851         try {
   1852             outs = mContext.openFileOutput(path, Context.MODE_PRIVATE);
   1853             GZIPOutputStream stream = new GZIPOutputStream(outs);
   1854             synchronized (callback) {
   1855                 web.saveViewState(stream, callback);
　　　　　　　　　　　　　　　　　　　　　　　　　　＝＞３へ　
　　　　　　　　　　　　　　　　　　　　　　　　　　＝＞CBをセットして３から戻ってくる。
   1856                 callback.wait();
   1857             }
   1858             stream.flush();
   1859             stream.close();
   1860         } catch (Exception e) {
   1861             Log.w(LOGTAG, "Failed to save view state", e);
   1862             if (outs != null) {
   1863                 try {
   1864                     outs.close();
   1865                 } catch (IOException ignore) {}
   1866             }
   1867             File file = mContext.getFileStreamPath(path);
   1868             if (file.exists() && !file.delete()) {
   1869                 file.deleteOnExit();
   1870             }
   1871             return false;
   1872         }
   1873         File savedFile = mContext.getFileStreamPath(path);
   1874         if (!callback.mResult) {
   1875             if (!savedFile.delete()) {
   1876                 savedFile.deleteOnExit();
   1877             }
   1878             return false;
   1879         }
   1880         long size = savedFile.length();
   1881         values.put(Snapshots.VIEWSTATE_PATH, path);
   1882         values.put(Snapshots.VIEWSTATE_SIZE, size);
   1883         return true;
   1884     }

３：frameworks/base/core/java/android/webkit/WebViewClassic.java

   2428     /**
   2429      * Saves the view data to the output stream. The output is highly
   2430      * version specific, and may not be able to be loaded by newer versions
   2431      * of WebView.
   2432      * @param stream The {@link OutputStream} to save to
   2433      * @param callback The {@link ValueCallback} to call with the result
   2434      */
   2435     public void saveViewState(OutputStream stream, ValueCallback<Boolean> callback) {
   2436         if (mWebViewCore == null) {
   2437             callback.onReceiveValue(false);
   2438             return;
   2439         }
   2440         mWebViewCore.sendMessageAtFrontOfQueue(EventHub.SAVE_VIEW_STATE,
   2441                 new WebViewCore.SaveViewStateRequest(stream, callback));
　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　＝＞　４のコンストラクタでObject作成
　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　＝＞　５へ
   2442     }

４：frameworks/base/core/java/android/webkit/WebViewCore.java

   1051     static class SaveViewStateRequest {
                コンストラクタ
   1052         SaveViewStateRequest(OutputStream s, ValueCallback<Boolean> cb) {
   1053             mStream = s;
   1054             mCallback = cb;
   1055         }
   1056         public OutputStream mStream;
   1057         public ValueCallback<Boolean> mCallback;
   1058     }

５：frameworks/base/core/java/android/webkit/WebViewCore.java

   1961     void sendMessageAtFrontOfQueue(int what, Object obj) {
   1962         mEventHub.sendMessageAtFrontOfQueue(Message.obtain(
   1963                 null, what, obj));
　　　　　　　　　　　　　　　　　　　　　＝＞EventHubのQueueへメッセージを送る。
   1964     }

６：frameworks/base/core/java/android/webkit/WebViewCore.java

   1753                         case SAVE_VIEW_STATE:＜＝メッセージ受信
   1754                             SaveViewStateRequest request = (SaveViewStateRequest) msg.obj;
   1755                             saveViewState(request.mStream, request.mCallback);
   1756                             break;

７：frameworks/base/core/java/android/webkit/WebViewCore.java

   2255     private void saveViewState(OutputStream stream,
   2256             ValueCallback<Boolean> callback) {
   2257         // TODO: Create a native method to do this better without overloading
   2258         // the draw path (and fix saving <canvas>)
   2259         DrawData draw = new DrawData();
   2260         if (DebugFlags.WEB_VIEW_CORE) Log.v(LOGTAG, "saveViewState start");
   2261         draw.mBaseLayer = nativeRecordContent(mNativeClass, draw.mContentSize);＜＝＝Native
   2262         boolean result = false;
   2263         try {
   2264             result = ViewStateSerializer.serializeViewState(stream, draw);
   2265         } catch (Throwable t) {
   2266             Log.w(LOGTAG, "Failed to save view state", t);
   2267         }
   2268         callback.onReceiveValue(result);
   2269         if (draw.mBaseLayer != 0) {
   2270             if (mDrawIsScheduled) {
   2271                 mDrawIsScheduled = false;
   2272                 mEventHub.removeMessages(EventHub.WEBKIT_DRAW);
   2273             }
   2274             mLastDrawData = draw;
   2275             webkitDraw(draw);
   2276         }
   2277     }