Android handler（工具类）弱引用 WeakReference

来源：互联网发布：淘宝代理软件是什么编辑：程序博客网时间：2024/05/16 01:31

转载：(http://blog.csdn.net/android_zhengyongbo/article/details/70046398)
handler弱引用可以在一定程度上防止内存泄露

handler弱引用的工具类

import android.os.Handler;
import android.os.Message;

import java.lang.ref.WeakReference;

/**
*

 
 *     author: Blankj 
 *     blog  : http://blankj.com 
 *     time  : 16/11/01 
 *     desc  : Handler相关工具类 
 *

*/
public final class HandlerUtils {

private HandlerUtils() {    throw new UnsupportedOperationException("u can't instantiate me...");}public static class HandlerHolder extends Handler {    WeakReference<OnReceiveMessageListener> mListenerWeakReference;    /**     * 使用必读：推荐在Activity或者Activity内部持有类中实现该接口，不要使用匿名类，可能会被GC     *     * @param listener 收到消息回调接口     */    public HandlerHolder(OnReceiveMessageListener listener) {        mListenerWeakReference = new WeakReference<>(listener);    }    @Override    public void handleMessage(Message msg) {        if (mListenerWeakReference != null && mListenerWeakReference.get() != null) {            mListenerWeakReference.get().handlerMessage(msg);        }    }}/** * 收到消息回调接口 */public interface OnReceiveMessageListener {    void handlerMessage(Message msg);}

}

使用示例

import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.Toast;public class MainActivity extends AppCompatActivity implements HandlerUtils.OnReceiveMessageListener{    private HandlerUtils.HandlerHolder handlerHolder;    private static final int M_ONE=12;    private static final int M_TWO=14;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        handlerHolder = new HandlerUtils.HandlerHolder(this);        handlerHolder.sendEmptyMessage(M_ONE);        handlerHolder.sendEmptyMessage(M_TWO);    }    @Override    public void handlerMessage(Message msg) {        switch (msg.what){            case M_ONE:                Toast.makeText(this, "M_ONE", Toast.LENGTH_SHORT).show();                break;            case M_TWO:                Toast.makeText(this, "M_TWO", Toast.LENGTH_SHORT).show();                break;        }    }}

0 0