Activity中onClick事件3种写法

package com.wyw.demo;

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

public class activity 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.EditText01);
//第一种方式
Button Btn1 = (Button)findViewById(R.id.Button01);//获取按钮资源
Btn1.setOnClickListener(new Button.OnClickListener(){//创建监听
@Override
public void onClick(View v) {
String strTmp = "点击Button01";
Ev1.setText(strTmp);
}
});

//第二种方式
Button Btn2 = (Button) findViewById(R.id.Button02);//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
@Override
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:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button android:text="Button01"
android:id="@+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Button>

<Button android:text="Button02"
android:id="@+id/Button02"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Button>

<Button android:text="Button03"
android:id="@+id/Button03"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="Btn3OnClick">
</Button>

<EditText android:text="@+id/EditText01"
android:id="@+id/EditText01"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</EditText>
</LinearLayout>