HandlerThread更新ui和Log日誌的用法
1、HandlerThread 用法例項
package com.example.handledemos;
import com.example.handledemos.util.LogUtil;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
/**
* 主執行緒與子執行緒之間的資訊互動
* @author lzl
*用到HandlerThread方法,主要解決多執行緒併發問題。
*/
public class HandlerThreadActivity extends Activity implements OnClickListener{
//建立主執行緒中的handler
private Handler handler = new Handler(){
public void handleMessage(android.os.Message msg) {
Message message = new Message();
//handlerthread每隔1秒向子執行緒傳送一次訊息。
handlerthread.sendMessageDelayed(message, 1000);
LogUtil.i("主執行緒", "Main send the message");
};
};
private Handler handlerthread;
private HandlerThread thread;
private Button button1;
private Button button2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.handlerthread);
button1 = (Button) findViewById(R.id.button1);
button2 = (Button) findViewById(R.id.button2);
button1.setOnClickListener(this);
button2.setOnClickListener(this);
thread = new HandlerThread("threadHandler");
thread.start();
handlerthread = new Handler(thread.getLooper()){
@Override
public void handleMessage(Message msg) {
Message message = new Message();
//handler每隔1秒向主執行緒傳送一次訊息。
handler.sendMessageDelayed(message, 1000);
LogUtil.i("子執行緒", "Thread send the message");
}
};
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.button1:
handler.sendEmptyMessage(1);
break;
case R.id.button2:
handler.removeMessages(0); //傳入0時會停止傳送訊息。
break;
default:
break;
}
}
}
2、Log控制列印,在完成大型專案後,執行程式是還會列印Log資訊,程式設計師不可能將其逐個刪除掉。因此可以寫個Util包,來控制Log日誌的列印。
當完成工程後,就不用擔心這個問題了。
package com.example.handledemos.util;
import android.util.Log;
public class LogUtil {
public static final int VERBOSE = 1;
public static final int DEBUG = 2;
public static final int INFO = 3;
public static final int WARN = 4;
public static final int ERROR = 5;
public static final int NOTHING = 6;
public static final int LEVEL = NOTHING;
public static void v(String tag , String msg){
if(LEVEL <= VERBOSE){
Log.v(tag, msg);
}
}
public static void d(String tag , String msg){
if(LEVEL <= DEBUG){
Log.d(tag, msg);
}
}
public static void i(String tag , String msg){
if(LEVEL <= INFO){
Log.i(tag, msg);
}
}
public static void w(String tag , String msg){
if(LEVEL <= WARN){
Log.w(tag, msg);
}
}
public static void e(String tag , String msg){
if(LEVEL <= ERROR){
Log.e(tag, msg);
}
}
}