android.os.Handler#obtainMessage ( )源码实例Demo

@Override
public void showRepostFormWarningDialog(final ContentViewCore contentViewCore) {
    // TODO(mkosiba) We should be using something akin to the JsResultReceiver as the
    // callback parameter (instead of ContentViewCore) and implement a way of converting
    // that to a pair of messages.
    final int MSG_CONTINUE_PENDING_RELOAD = 1;
    final int MSG_CANCEL_PENDING_RELOAD = 2;

    // TODO(sgurun) Remember the URL to cancel the reload behavior
    // if it is different than the most recent NavigationController entry.
    final Handler handler = new Handler(ThreadUtils.getUiThreadLooper()) {
        @Override
        public void handleMessage(Message msg) {
            switch(msg.what) {
                case MSG_CONTINUE_PENDING_RELOAD: {
                    contentViewCore.continuePendingReload();
                    break;
                }
                case MSG_CANCEL_PENDING_RELOAD: {
                    contentViewCore.cancelPendingReload();
                    break;
                }
                default:
                    throw new IllegalStateException(
                            "WebContentsDelegateAdapter: unhandled message " + msg.what);
            }
        }
    };

    Message resend = handler.obtainMessage(MSG_CONTINUE_PENDING_RELOAD);
    Message dontResend = handler.obtainMessage(MSG_CANCEL_PENDING_RELOAD);
    mContentsClient.onFormResubmission(dontResend, resend);
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
	Point cameraResolution = configManager.getCameraResolution();
	Handler thePreviewHandler = previewHandler;
	if (cameraResolution != null && thePreviewHandler != null) {
		Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x, cameraResolution.y,
				data);
		message.sendToTarget();
		previewHandler = null;
	} else {
		Log.d(TAG, "Got preview callback, but no handler or resolution available");
	}
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
  Point cameraResolution = configManager.getCameraResolution();
  Handler thePreviewHandler = previewHandler;
  if (cameraResolution != null && thePreviewHandler != null) {
    Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
        cameraResolution.y, data);
    message.sendToTarget();
    previewHandler = null;
  } else {
    Log.d(TAG, "Got preview callback, but no handler or resolution available");
  }
}
 

public void updateAppWidget(int appWidgetId, RemoteViews views) {
    if (isLocalBinder() && views != null) {
        views = views.clone();
    }
    Handler handler = mWeakHandler.get();
    if (handler == null) {
        return;
    }
    Message msg = handler.obtainMessage(HANDLE_UPDATE, appWidgetId, 0, views);
    msg.sendToTarget();
}
 

public void viewDataChanged(int appWidgetId, int viewId) {
    Handler handler = mWeakHandler.get();
    if (handler == null) {
        return;
    }
    Message msg = handler.obtainMessage(HANDLE_VIEW_DATA_CHANGED,
            appWidgetId, viewId);
    msg.sendToTarget();
}
 

public static void freeJunkInfos(ArrayList<JunkInfo> junks, final Handler handler) {
    for (JunkInfo info : junks) {
        File file = new File(info.mPath);
        if (file != null && file.exists()) {
            file.delete();
        }
    }

    Message msg = handler.obtainMessage(JunkCleanActivity.MSG_OVERALL_CLEAN_FINISH);
    msg.sendToTarget();
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    Point cameraResolution = configManager.getCameraResolution();
    Handler thePreviewHandler = previewHandler;
    if (cameraResolution != null && thePreviewHandler != null) {
        Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
                cameraResolution.y, data);
        message.sendToTarget();
        previewHandler = null;
    } else {
        Log.d(TAG, "Got preview callback, but no handler or resolution available");
    }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
  Point cameraResolution = configManager.getCameraResolution();
  Handler thePreviewHandler = previewHandler;
  if (cameraResolution != null && thePreviewHandler != null) {
    Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
        cameraResolution.y, data);
    message.sendToTarget();
    previewHandler = null;
  } else {
    Log.d(TAG, "Got preview callback, but no handler or resolution available");
  }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    Camera.Size cameraResolution = configManager.getCameraResolution();
    Handler thePreviewHandler = previewHandler;
    if (cameraResolution != null && thePreviewHandler != null) {
        Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.width,
                cameraResolution.height, data);
        message.sendToTarget();
        previewHandler = null;
    } else {
        Log.d(TAG, "Got preview callback, but no handler or resolution available");
    }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
	Point cameraResolution = configManager.getCameraResolution();
	Handler thePreviewHandler = previewHandler;
	if (cameraResolution != null && thePreviewHandler != null) {
		Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x, cameraResolution.y,
				data);
		message.sendToTarget();
		previewHandler = null;
	} else {
		Log.d(TAG, "Got preview callback, but no handler or resolution available");
	}
}
 

public static void sendMessage(Handler handler, int what, int arg1, Bundle bundle) {

        Message msg = handler.obtainMessage();

        msg.what = what;
        msg.arg1 = arg1;
        msg.setData(bundle);

        // 发送消息
        handler.sendMessage(msg);
    }
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
	Point cameraResolution = configManager.getCameraResolution();
	Handler thePreviewHandler = previewHandler;
	if (cameraResolution != null && thePreviewHandler != null) {
		Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x, cameraResolution.y,
				data);
		message.sendToTarget();
		previewHandler = null;
	} else {
		Log.d(TAG, "Got preview callback, but no handler or resolution available");
	}
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
  Point cameraResolution = configManager.getCameraResolution();
  Handler thePreviewHandler = previewHandler;
  if (thePreviewHandler != null) {
    Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
        cameraResolution.y, data);
    message.sendToTarget();
    previewHandler = null;
  } else {
    Log.d(TAG, "Got preview callback, but no handler for it");
  }
}
 

/**
 * commit the data for exposure event in batch
 */
private void batchReport() {
    long time = System.currentTimeMillis();

    Handler handler = ExposureManager.getInstance().getExposureHandler();
    Message message = handler.obtainMessage();
    message.what = ExposureManager.BATCH_COMMIT_EXPOSURE;
    handler.sendMessage(message);

    TrackerLog.v("batch report exposure views " + (System.currentTimeMillis() - time) + "ms");
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    Point cameraResolution = configManager.getCameraResolution();
    Handler thePreviewHandler = previewHandler;
    if (cameraResolution != null && thePreviewHandler != null) {
        Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
                cameraResolution.y, data);
        message.sendToTarget();
        previewHandler = null;
    } else {
        Log.d(TAG, "Got preview callback, but no handler or resolution available");
    }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    Point cameraResolution = configManager.getCameraResolution();
    Handler thePreviewHandler = previewHandler;
    if (cameraResolution != null && thePreviewHandler != null) {
        Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
                cameraResolution.y, data);
        message.sendToTarget();
        previewHandler = null;
    } else {
        Log.d(TAG, "Got preview callback, but no handler or resolution available");
    }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    Point cameraResolution = configManager.getCameraResolution();
    Handler thePreviewHandler = previewHandler;
    if (thePreviewHandler != null) {
        Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x, cameraResolution.y, data);
        message.sendToTarget();
        previewHandler = null;
    } else {
        Log.d(TAG, "Got preview callback, but no handler for it");
    }
}
 

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
  Point cameraResolution = configManager.getCameraResolution();
  Handler thePreviewHandler = previewHandler;
  if (cameraResolution != null && thePreviewHandler != null) {
    Message message = thePreviewHandler.obtainMessage(previewMessage, cameraResolution.x,
        cameraResolution.y, data);
    message.sendToTarget();
    previewHandler = null;
  } else {
    Log.d(TAG, "Got preview callback, but no handler or resolution available");
  }
}
 

public Message obtainRequest(Handler handler, String action, Uri uri) {
    Message msg = handler.obtainMessage(REQUEST, action.hashCode(), Uris.getDescriptor(uri));
    return msg;
}
 

public static void sendMessage(Handler handler, int what, Object obj) {

        Message msg = handler.obtainMessage();

        msg.what = what;
        msg.obj = obj;

        // 发送消息
        handler.sendMessage(msg);
    }