Android 的 Button 按钮实现的两种方式

第一组方式：

res/laoyout/activity_main.xml 代码：

<RelativeLayout 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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="51dp"
        android:layout_toRightOf="@+id/textView1"
        android:text="按钮" />

</RelativeLayout>

MainActivity.java 代码：

package com.example.testbutton;

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

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final Button bt = (Button) findViewById (R.id.button);

        bt.setOnClickListener(new OnClickListener(){
            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Toast.makeText(MainActivity.this,"亲，你点击按钮了 ",1000).show();
            }
        }) ;
    }

}

第二组方式：

我们可以在布局文件中的Button属性中设置 onClick事件，

<RelativeLayout 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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="51dp"
        android:layout_toRightOf="@+id/textView1"
        android:onClick="clickMyself"
        android:text="按钮" />

</RelativeLayout>

MainActivity.java 代码：

package com.example.testbutton;

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

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final Button bt = (Button) findViewById (R.id.button);
    }
    public void clickMyself(View view){
        Toast.makeText(MainActivity.this, "按钮被点击了", 2000).show();

    }

}