兔子--AlertDialog

        效果：

实现步骤：

1.定义AlertDialog的布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="100dp"
    android:layout_height="100dp"
    android:background="@android:color/holo_green_dark" > 

    <ImageView
        android:id="@+id/imageView_background_mydialog"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:src="@drawable/ic_launcher" />   
</RelativeLayout>

2.创建Activity。布局例如以下

<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/myBtn"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="show dialog"  
        android:textSize="22dip"  
         />  


</RelativeLayout>

MainActivity.java

package com.example.alertdialog;


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


public class MainActivity extends Activity {
private Button btn = null;
private AlertDialog myDialog = null;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button) findViewById(R.id.myBtn);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
myDialog = new AlertDialog.Builder(MainActivity.this).create();
myDialog.show();
myDialog.getWindow().setContentView(R.layout.dialog);


}
});
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}


}