Android 防内存泄露handler

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<Handler.Callback> 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();
    }
    }

-Github演示样例參考代码

參考作者：-Coding-Android作者