Android的AlertDialog详解

本篇文章转载自：http://www.2cto.com/kf/201205/131876.html

AlertDialog的构造方法全部是Protected的，所以不能直接通过new一个AlertDialog来创建出一个AlertDialog。

要创建一个AlertDialog，就要用到AlertDialog.Builder中的create()方法。

使用AlertDialog.Builder创建对话框需要了解以下几个方法：

setTitle ：为对话框设置标题

setIcon ：为对话框设置图标

setMessage：为对话框设置内容

setView ： 给对话框设置自定义样式

setItems ：设置对话框要显示的一个list，一般用于显示几个命令时

setMultiChoiceItems ：用来设置对话框显示一系列的复选框

setNeutralButton ：普通按钮

setPositiveButton ：给对话框添加"Yes"按钮

setNegativeButton ：对话框添加"No"按钮

create ： 创建对话框

show ：显示对话框

一、简单的AlertDialog

下面，创建一个简单的ALertDialog并显示它：

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.os.Bundle;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("对话框的标题").

setMessage("对话框的内容").

setIcon(R.drawable.ic_launcher).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.os.Bundle;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("对话框的标题").

setMessage("对话框的内容").

setIcon(R.drawable.ic_launcher).

create();

alertDialog.show();

}

}运行结果如下：



二、带按钮的AlertDialog

上面的例子很简单，下面我们在这个AlertDialog上面加几个Button，实现删除操作的提示对话框

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("确定删除？").

setMessage("您确定删除该条信息吗？").

setIcon(R.drawable.ic_launcher).

setPositiveButton("确定", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNeutralButton("查看详情", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("确定删除？").

setMessage("您确定删除该条信息吗？").

setIcon(R.drawable.ic_launcher).

setPositiveButton("确定", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNeutralButton("查看详情", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}在这个例子中，我们定义了三个按钮，分别是"Yes"按钮，"No"按钮以及一个普通按钮，每个按钮都有onClick事件，TODO的地方可以放点了按钮之后想要做的一些处理

看一下运行结果：



可以看到三个按钮添加到了AlertDialog上，三个没有添加事件处理的按钮，点了只是关闭对话框，没有任何其他操作。

三、类似ListView的AlertDialog

用setItems(CharSequence[] items, final OnClickListener listener)方法来实现类似ListView的AlertDialog

第一个参数是要显示的数据的数组，第二个参数是点击某个item的触发事件

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setItems(arrayFruit, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

Toast.makeText(Dialog_AlertDialogDemoActivity.this, arrayFruit[which], Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setItems(arrayFruit, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

Toast.makeText(Dialog_AlertDialogDemoActivity.this, arrayFruit[which], Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}运行结果如下：



四、类似RadioButton的AlertDialog

用setSingleChoiceItems(CharSequence[] items, int checkedItem, final OnClickListener listener)方法来实现类似RadioButton的AlertDialog

第一个参数是要显示的数据的数组，第二个参数是初始值（初始被选中的item），第三个参数是点击某个item的触发事件

在这个例子里面我们设了一个selectedFruitIndex用来记住选中的item的index

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

private int selectedFruitIndex = 0;

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setSingleChoiceItems(arrayFruit, 0, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

selectedFruitIndex = which;

}

}).

setPositiveButton("确认", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

Toast.makeText(Dialog_AlertDialogDemoActivity.this, arrayFruit[selectedFruitIndex], Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

private int selectedFruitIndex = 0;

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setSingleChoiceItems(arrayFruit, 0, new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

selectedFruitIndex = which;

}

}).

setPositiveButton("确认", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

Toast.makeText(Dialog_AlertDialogDemoActivity.this, arrayFruit[selectedFruitIndex], Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

运行结果如下：



五、类似CheckBox的AlertDialog

用setMultiChoiceItems(CharSequence[] items, boolean[] checkedItems, final OnMultiChoiceClickListener listener)方法来实现类似CheckBox的AlertDialog

第一个参数是要显示的数据的数组，第二个参数是选中状态的数组，第三个参数是点击某个item的触发事件

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

final boolean[] arrayFruitSelected = new boolean[] {true, true, false, false};

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setMultiChoiceItems(arrayFruit, arrayFruitSelected, new DialogInterface.OnMultiChoiceClickListener() {

@Override

public void onClick(DialogInterface dialog, int which, boolean isChecked) {

arrayFruitSelected[which] = isChecked;

}

}).

setPositiveButton("确认", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

StringBuilder stringBuilder = new StringBuilder();

for (int i = 0; i < arrayFruitSelected.length; i++) {

if (arrayFruitSelected[i] == true)

{

stringBuilder.append(arrayFruit[i] + "、");

}

}

Toast.makeText(Dialog_AlertDialogDemoActivity.this, stringBuilder.toString(), Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.widget.Toast;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉" };

final boolean[] arrayFruitSelected = new boolean[] {true, true, false, false};

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("你喜欢吃哪种水果？").

setIcon(R.drawable.ic_launcher)

.setMultiChoiceItems(arrayFruit, arrayFruitSelected, new DialogInterface.OnMultiChoiceClickListener() {

@Override

public void onClick(DialogInterface dialog, int which, boolean isChecked) {

arrayFruitSelected[which] = isChecked;

}

}).

setPositiveButton("确认", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

StringBuilder stringBuilder = new StringBuilder();

for (int i = 0; i < arrayFruitSelected.length; i++) {

if (arrayFruitSelected[i] == true)

{

stringBuilder.append(arrayFruit[i] + "、");

}

}

Toast.makeText(Dialog_AlertDialogDemoActivity.this, stringBuilder.toString(), Toast.LENGTH_SHORT).show();

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}运行结果如下：



六、自定义View的AlertDialog

有时候我们不能满足系统自带的AlertDialog风格，就比如说我们要实现一个Login画面，有用户名和密码，这时我们就要用到自定义View的AlertDialog

先创建Login画面的布局文件

[html] <?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="fill_parent"

android:orientation="vertical" >

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:gravity="center" >

<TextView

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1"

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

<EditText

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1" />

</LinearLayout>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:gravity="center" >

<TextView

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1"

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

<EditText

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1" />

</LinearLayout>

< /LinearLayout>

< ?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="fill_parent"

android:orientation="vertical" >

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:gravity="center" >

<TextView

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1"

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

<EditText

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1" />

</LinearLayout>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:gravity="center" >

<TextView

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1"

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

<EditText

android:layout_width="0dip"

android:layout_height="wrap_content"

android:layout_weight="1" />

</LinearLayout>

</LinearLayout>

然后在Activity里面把Login画面的布局文件添加到AlertDialog上

[java] package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.view.LayoutInflater;

import android.view.View;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

// 取得自定义View

LayoutInflater layoutInflater = LayoutInflater.from(this);

View myLoginView = layoutInflater.inflate(R.layout.login, null);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("用户登录").

setIcon(R.drawable.ic_launcher).

setView(myLoginView).

setPositiveButton("登录", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}

package com.tianjf;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.Dialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.view.LayoutInflater;

import android.view.View;

public class Dialog_AlertDialogDemoActivity extends Activity {

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

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

// 取得自定义View

LayoutInflater layoutInflater = LayoutInflater.from(this);

View myLoginView = layoutInflater.inflate(R.layout.login, null);

Dialog alertDialog = new AlertDialog.Builder(this).

setTitle("用户登录").

setIcon(R.drawable.ic_launcher).

setView(myLoginView).

setPositiveButton("登录", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

// TODO Auto-generated method stub

}

}).

create();

alertDialog.show();

}

}运行结果如下：



摘自 殇雲的专栏