Android 防内存泄露handler

1.使用弱引用 WeakRefHander

/**     * 作者: allen on 15/11/24.感谢开源作者https://coding.net/u/coding/p/Coding-Android/git     */    /**     * 弱引用 handler 防止内存泄露     */    public class WeakRefHander extends Handler {
              private final WeakReference
      
        mRef;        private final int mLoopTime;        private int NO_LOOP = -1;        private int what =0;        /**         * 循环         *         * @param loopAction         * @param loopTime         */        public WeakRefHander(Handler.Callback loopAction, int loopTime) {            super();            this.mRef = new WeakReference<>(loopAction);            this.mLoopTime = loopTime;        }        /**         * 不循环         *         * @param loopAction         */        public WeakRefHander(Handler.Callback loopAction) {            super();            mRef = new WeakReference<>(loopAction);            mLoopTime = NO_LOOP;        }        @Override        public void handleMessage(Message msg) {            Handler.Callback action = mRef.get();            if (action != null) {                action.handleMessage(msg);                if (mLoopTime != NO_LOOP) {                    sendEmptyMessageDelayed(what, mLoopTime);                }            }        }        public void start() {            removeMessages(0);            sendEmptyMessageDelayed(0, 0);        }        public void start(int what, long delay) {            this.what = what;            removeMessages(what);            sendEmptyMessageDelayed(what, delay);        }        public void stop() {            removeMessages(what);        }        public void clear() {            removeMessages(what);            mRef.clear();            }        }

2. 实现 Activity implements WeakRefHander.Callback

3. 在handleMessage处理业务逻辑

演示样例代码:

public class MainActivity extends AppCompatActivity implements WeakRefHander.Callback {
              private WeakRefHander weakRefHander;        private static final int HANDLER_MESSAGE_START = 1001;        @Override        protected void onCreate(Bundle savedInstanceState) {            super.onCreate(savedInstanceState);            setContentView(R.layout.activity_main);            weakRefHander = new WeakRefHander(this, 1);            weakRefHander.start(HANDLER_MESSAGE_START, 1000 * 30);    }    @Override    public boolean handleMessage(Message msg) {        switch (msg.what) {            case HANDLER_MESSAGE_START:                //Todo 处理业务逻辑                break;            default:                break;        }        return true;    }    @Override    public void onResume() {        super.onResume();        weakRefHander.start();    }    @Override    public void onPause() {        weakRefHander.stop();        super.onPause();    }    @Override    protected void onDestroy() {        weakRefHander.clear();        super.onDestroy();    }    }