Android开发之onClick事件的三种写法(转)

 package a.a;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;

 public class AActivity extends Activity {
     /** Called when the activity is first created. */

     EditText Ev1;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);

         Ev1 = (EditText)findViewById(R.id.editText1);  

         //第一种方式
         Button Btn1 = (Button)findViewById(R.id.button1);//获取按钮资源
         Btn1.setOnClickListener(new Button.OnClickListener(){//创建监听
             public void onClick(View v) {
                 String strTmp = "点击Button01";
                 Ev1.setText(strTmp);
             }  

         });  

         //第二种方式
         Button Btn2 = (Button) findViewById(R.id.button2);//获取按钮资源
         Btn2.setOnClickListener(listener);//设置监听  

     }

     Button.OnClickListener listener = new Button.OnClickListener(){//创建监听对象
         public void onClick(View v){
             String strTmp="点击Button02";
             Ev1.setText(strTmp);
         }  

     };

     //第三种方式(Android1.6版本及以后的版本中提供了)
     public void Btn3OnClick(View view){
         String strTmp="点击Button03";
         Ev1.setText(strTmp);

     }
 }

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:orientation="vertical" >

     <TextView
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:text="@string/hello" />

     <Button
         android:id="@+id/button1"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="Button1" />

     <Button
         android:id="@+id/button2"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="Button2" />

  <Button
         android:id="@+id/button3"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="Button3"
         android:onClick="Btn3OnClick"/>

  <EditText
      android:id="@+id/editText1"
      android:layout_width="match_parent"
      android:layout_height="wrap_content" >

      <requestFocus />
  </EditText>

 </LinearLayout>