Activity # runOnUiThread 与 View # post

There is no real difference, except that the View.post is helpful when you don't have a direct access to the activity.

    public boolean post(Runnable action) {
       Handler handler;
        if (mAttachInfo != null) {
           handler = mAttachInfo.mHandler;
      } else {
            // Assume that post will succeed later
           ViewRoot.getRunQueue().post(action);
           return true;
        }

        return handler.post(action);
    }

    public final void runOnUiThread(Runnable action) {
        if (Thread.currentThread() != mUiThread) {
            mHandler.post(action);
        } else {
            action.run();
        }
    }