Android更新UI的几种方法

• handler发送消息给主线程更新ui
• Activity的runOnUiThread() 方法。

/**
 * Runs the specified action on the UI thread. If the current thread is the UI
 * thread, then the action is executed immediately. If the current thread is
 * not the UI thread, the action is posted to the event queue of the UI thread.
 *
 * @param action the action to run on the UI thread
 */
public final void runOnUiThread(Runnable action) {
    if (Thread.currentThread() != mUiThread) {
        mHandler.post(action);
    } else {
        action.run();
    }
}

• View.post(Runnable r)方法。

boolean android.view.View .post(Runnable action)

//Causes the Runnable to be added to the message queue. The runnable will be //run on the user interface thread.

• BroadcastReceiver运行在主线程，可以更新UI。同样其中不能进行耗时操作