Android Handler避免内存泄漏的简便写法

    //Handler避免内存泄漏的正确写法,采用弱引用用Handler.Callback来实现,可有效避免内存泄漏
    private Handler launchHandler = new Handler(new WeakReference(    
        new Handler.Callback() {
        @Override
        public boolean handleMessage(Message msg) {
            //code...
            return true;
        }
    }).get());

通常直接new Handler 重写handleMessage编译器会提醒有内存泄漏隐患,采用弱引用的写法可有效避免内存泄漏,关于Handler.Callback的返回值看源码

    /**
     * Handle system messages here.
     */
    public void dispatchMessage(Message msg) {
        if (msg.callback != null) {
            handleCallback(msg);
        } else {
            if (mCallback != null) {
                if (mCallback.handleMessage(msg)) {
                    return;
                }
            }
            handleMessage(msg);
        }
    }

得知如果该方法mCallback.handleMessage返回true不会执行Handler的handlerMessage方法