package com.narumi.android_7_2;

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.main);

        Button btn = (Button)findViewById(R.id.button1);

        btn.setOnClickListener(

                new OnClickListener() {

            @Override

            public void onClick(View v) {

                // TODO Auto-generated method stub

                Toast.makeText(MainActivity.this, "你已经点了我", 2000).show();

            }

        });

    }

}

<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="com.narumi.android_7_2.MainActivity" >

    <TextView

        android:id="@+id/textView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="@string/hello_world" />

    <Button

        android:id="@+id/button1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_below="@id/textView1"

        android:layout_marginTop="48dp"

        android:layout_toRightOf="@id/textView1"

        android:text="点我试试" />

</RelativeLayout>