关于Android Handler机制的封

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Android 与 Java最大的不同在于Handler机制, 通常比较耗时的操作例如网络IO或各种复杂的计算等都是新开子线程中进行的, 若放在主线程中,若超时会导致ANR错误, 但是子线程又不允许更新UI内容, 为了解决这个矛盾Android 巧妙的设计了Handler机制, 因为以前接触的部分项目均为与条码相关的项目，有些Android设备在进行条码扫描时,扫描的驱动会通过Handler机制发送Message对象来实现，因为在Activity中频繁的用到Handler,所以为了提高代码的复用性,想针对条码设备的Handler机制进行封装以提高开发的效率, 在网上搜索过此类问题的解决方案没有找到太多有价值的信息,经过自己对Handler的理解提出以下解决办法,若有不妥之处,或更好的解决方案希望大家能指正留言,不吝赐教,谢谢

package com.fzhang.util;import android.content.Context;import android.os.Handler;import android.os.Message;import android.os.RemoteException;import android.os.Vibrator;import com.mobilead.decodemanager.DecodeManager;import com.mobilead.decodemanager.barcode.DecodeResult;import java.io.IOException;/** * Created by fzhang on 2016/12/9. */public class M80Util {        public Context context;    private Handler mHandler;    private Runnable runnable;    private String barcode;    private DecodeManager decodeManager;    private static final long[] VIBRATE_FAILED = {100, 400, 100, 400};    private static final long[] VIBRATE_SUCESS = {100, 400};    private Vibrator vibrator = null;    public M80Util(final Context context, final Runnable runnable) {        this.context = context;        //将handler对象与对应context的主Looper进行绑定        new Thread(new Runnable() {            @Override public void run() {                mHandler = new Handler(context.getMainLooper()){                    @Override public void handleMessage(Message msg) {                        super.handleMessage(msg);                        switch (msg.what) {                            case DecodeManager.MESSAGE_DECODER_COMPLETE:                                DecodeResult result = (DecodeResult) msg.obj;                                barcode = result.barcodeData;                                runnable.run();                                break;                            case DecodeManager.MESSAGE_DECODER_FAIL:                                break;                        }                    }                };                decodeManager = new DecodeManager(context,mHandler);                SoundManager.getInstance();                SoundManager.initSounds(context);                SoundManager.loadSounds();                vibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);            }        }).start();            }    public Handler getmHandler() {        return mHandler;    }    public void setmHandler(Handler mHandler) {        this.mHandler = mHandler;    }        public void decode() {        try {            this.decodeManager.doDecode(3000);        } catch (RemoteException e) {            e.printStackTrace();        }    }    public String getBarcode() {        return barcode;    }        public void close() {        try {            decodeManager.release();            SoundManager.cleanup();            decodeManager = null;        } catch (IOException e) {            e.printStackTrace();        }    }        public void good() {        SoundManager.playSound(1, 1);        vibrator.vibrate(VIBRATE_SUCESS, -1);    }        public void nogood() {        SoundManager.playSound(2, 1);        vibrator.vibrate(VIBRATE_FAILED, -1);    }}

调用的代码如下：

package com.jyjs.Activity;import android.os.Bundle;import android.os.Handler;import android.support.v7.app.AppCompatActivity;import android.widget.Button;import android.widget.TextView;import android.widget.Toast;import com.fzhang.util.M80Util;import com.jyjs.R;import butterknife.BindView;import butterknife.ButterKnife;import butterknife.OnClick;public class MainActivity extends AppCompatActivity {    long sta = 0, end = 0;    Handler handler;//未封装以前需要编写初始化每个Activity的Handler的大量代码    M80Util m80Util;//扫描解码工具类    @BindView(R.id.button2) Button btn_start;    @BindView(R.id.button3) Button btn_end;    @BindView(R.id.tv_1) public TextView tv_1;    Runnable runnable = new Runnable() {        @Override public void run() {            tv_1.setText("fuck Android!!!");        }    };    @Override        protected void onCreate(Bundle savedInstanceState) {            super.onCreate(savedInstanceState);            setContentView(R.layout.activity_main);            ButterKnife.bind(this);            m80Util = new M80Util(MainActivity.this,new Runnable(){                @Override public void run() {                    tv_1.setText(m80Util.getBarcode());                }            });            handler = m80Util.getmHandler();    }    @Override protected void onPause() {        super.onPause();        m80Util.close();    }    @OnClick(R.id.button2)    public void btn_start() {        m80Util.decode();//解码        m80Util.good();//解码正确产生提示音和一次震动    }    @OnClick(R.id.button3)    public void btn_end() {        Toast.makeText(MainActivity.this, "Clear", Toast.LENGTH_SHORT).show();        tv_1.setText("");        m80Util.nogood();//产生不正确提示音和两次震动    }}

另外若其他子线程中需要修改UI内容的直接可通过handler.post(runnable)方式直接实现

如此完成了对Handler机制的简单封装

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