这个例子不错,详细讲解了alertdialog及LayoutInflater的用法:

main.xml:

<?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:id="@+id/Button01" android:layout_height="wrap_content" android:text="非Layout型对话框" android:layout_width="fill_parent"></Button>

<Button android:id="@+id/Button02" android:layout_height="wrap_content" android:text="Layout型对话框" android:layout_width="fill_parent"></Button><View android:id="@+id/View01" android:layout_width="wrap_content" android:layout_height="wrap_content"></View>


</LinearLayout>


dialoglayout.xml:

<?xml version="1.0" encoding="utf-8"?>


<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent" android:layout_height="wrap_content"

android:orientation="vertical">

<EditText android:layout_height="wrap_content"

android:layout_width="fill_parent" android:layout_marginLeft="20dip"

android:layout_marginRight="20dip" android:textAppearance="?android:attr/textAppearanceMedium" android:id="@+id/edtInput"/>

</LinearLayout>


package com.testAlertDialog;


import android.app.Activity;

import android.app.AlertDialog;

import android.content.Context;

import android.content.DialogInterface;

import android.os.Bundle;

import android.view.Gravity;

import android.view.LayoutInflater;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.PopupWindow;



public class testAlertDialog extends Activity {

Button btnShowDialog;

Button btnShowDialog_Layout;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

//定义按钮

btnShowDialog=(Button)this.findViewById(R.id.Button01);

btnShowDialog.setOnClickListener(new ClickEvent());

btnShowDialog_Layout=(Button)this.findViewById(R.id.Button02);

btnShowDialog_Layout.setOnClickListener(new ClickEvent());

}





//统一处理按键事件

class ClickEvent implements OnClickListener{


@Override

public void onClick(View v) {

// TODO Auto-generated method stub

if(v==btnShowDialog)

showDialog(testAlertDialog.this);



else if(v==btnShowDialog_Layout)

showDialog_Layout(testAlertDialog.this);



}


}


//显示基本的AlertDialog

private void showDialog(Context context) {

AlertDialog.Builder builder = new AlertDialog.Builder(context);

builder.setIcon(R.drawable.icon);

builder.setTitle("Title");

builder.setMessage("Message");

builder.setPositiveButton("Button1",

new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

setTitle("点击了对话框上的Button1");

}

});

builder.setNeutralButton("Button2",

new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

setTitle("点击了对话框上的Button2");

}

});

builder.setNegativeButton("Button3",

new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

setTitle("点击了对话框上的Button3");

}

});

builder.show();

}



//显示基于Layout的AlertDialog

private void showDialog_Layout(Context context) {

LayoutInflater inflater = LayoutInflater.from(this);

final View textEntryView = inflater.inflate(

R.layout.dialoglayout, null);

final EditText edtInput=(EditText)textEntryView.findViewById(R.id.edtInput);

final AlertDialog.Builder builder = new AlertDialog.Builder(context);

builder.setCancelable(false);

builder.setIcon(R.drawable.icon);

builder.setTitle("Title");

builder.setView(textEntryView);

builder.setPositiveButton("确认",

new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

setTitle(edtInput.getText());

}

});

builder.setNegativeButton("取消",

new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int whichButton) {

setTitle("");

}

});

builder.show();

}

}




小结下:
1对于button,可以学上面这样,统一的一个事件去处理.

2 在实际开发种LayoutInflater这个类还是非常有用的,它的作用类似于 findViewById(),
不同点是LayoutInflater是用来找layout下xml布局文件,并且实例化!而findViewById()是找具体xml下的具体 widget控件(如:Button,TextView等)。

3 注意这里AlertDialog.Builder 的用法