问题 Today I read some blogs and source code about how Handler & Looper work together. Based on what I've learnt, we can have only one Looper on each thread by using the ThreadLocal magic. Usually Handler is initiated in main thread, or else you must manually start or saying, prepare the Looper on a separate thread and then loop it up. class LooperThread extends Thread { public Handler mHandler; public void run() { Looper.prepare(); mHandler = new Handler() { public void handleMessage(Message msg)