Android 防内存泄露handler

时间:2023-03-08 15:35:02

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