Button控件监听器的三种实现方法

Button按钮控件监听器的三种实现方法：

1、匿名内部类实现

2、外部类监听实现

3、接口方式实现

首先在布局文件中添加三个按钮，每个button对应实现一种实现方法

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.click.MainActivity" 
    android:orientation="vertical">

    <Button
        android:id="@+id/button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="内部类" />

    <Button
        android:id="@+id/button_2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="外部类" />

    <Button
        android:id="@+id/button_3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="接口" />

</LinearLayout>

第一种：内部类实现监听

button = (Button)findViewById(R.id.button);
button.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "click", 2000).show();
}
});

第二种：外部类实现监听

 button_2 = (Button)findViewById(R.id.button_2);
 button_2.setOnClickListener(new MyClick(){
        @Override
        public void onClick(View v) {
super.onClick(v);
        Toast.makeText(getApplicationContext(), "click2", 2000).show();
    }
});

//并实现外部类

class MyClick implements OnClickListener{@Overridepublic void onClick(View v) {

//所有重写该方法的，且调用super.onClick(v);，都会执行的逻辑v.setAlpha(0.5f);}}

第三种：接口方式实现监听

button_3 = (Button)findViewById(R.id.button_3);
button_3.setOnClickListener(this);

//并重写onClick方法

@Override

public void onClick(View v) {Toast.makeText(getApplicationContext(), "click3", 2000).show();}

贴上全部的代码

package com.example.click;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;


public class MainActivity extends Activity implements OnClickListener{

private Button button,button_2,button_3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        button = (Button)findViewById(R.id.button);
        button.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "click", 2000).show();
}
});
        button_2 = (Button)findViewById(R.id.button_2);
        button_2.setOnClickListener(new MyClick(){
        @Override
        public void onClick(View v) {
        super.onClick(v);
        Toast.makeText(getApplicationContext(), "click2", 2000).show();
    }
        });
        button_3 = (Button)findViewById(R.id.button_3);
        button_3.setOnClickListener(this);

    }

@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "click3", 2000).show();
}

}

class MyClick implements OnClickListener{

@Override
public void onClick(View v) {

v.setAlpha(0.5f);
}

}