【WP7进阶】——分享一个可供切换状态的ListBox组件
2011-02-20 19:57 Terry_龙 阅读(4488) 评论(14) 编辑 收藏 举报编写Asp.net的同学，经常会遇到一个Repeater 或者一个GridView ，当用户点击编辑状态时我们的列表组件会自动跳转到可选择（可供删除、编辑、选择等）状态。这时候一般的做法都会在组件的前方自动生成一系列复选框“CheckBox”，需要删除/选择哪行时只要在前方的复选框勾一下，便可以得到该行的数据或者行ID等。
上面的做法是一个比较典型的Web做法，那么在WP7 里面要实现这样的效果如何实现呢？有些同学就会说了，那简单使用ListBox 在它的数据模板里面添加一个CheckBox不就完事了吗？是的，这样是一种做法，但带来的问题是你得去控制他选中哪行并且得到哪行的ID，并且在WP7 有限的屏幕中这种做法比较不妥，当用户想做选择时，我们才让对应的行有可供选择的状态才更佳。而这种做法在传统的WP7控件中，是没有的。因为我们必须时时去控制它的复选框显示或者隐藏，但在这里我推荐大家一个组件，自带CheckBOx并且默认有两种状态，一种为普通状态即呈现数据显示给用户，如下图：
另外一种状态为可选择状态，即用户可以对相应的行做删除等操作，如下图：
该组件的下载地址为：WindowsPhoneListBoxWithCheckBoxesControl
下面给出该组件的详细用法：
做过.Net 开发的对于如何使该组件的应该很清楚，这里将跳过此步骤。
如上图，该组件编写的XAML代码为如下：
<my:ListBoxWithCheckBoxes Name="listBoxWithBoxes" Margin="0,0,0,0" ItemsSource="{Binding SimpleModels}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="0,0,0,20">
<Rectangle Height="100" Width="100" Fill="#FFE5001b" Margin="12,0,9,0"/>
<StackPanel>
<TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextLargeStyle}"/>
<TextBlock Text="{Binding Description}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</my:ListBoxWithCheckBoxes>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="0,0,0,20">
<Rectangle Height="100" Width="100" Fill="#FFE5001b" Margin="12,0,9,0"/>
<StackPanel>
<TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextLargeStyle}"/>
<TextBlock Text="{Binding Description}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</my:ListBoxWithCheckBoxes>
如上代码的数据模板，并未出现有CheckBox 控件，因为该组件己经将CheckBox控件整合在里面的选择状态中了。下面是具体如何为该组件添加数据。
首先该组件对应的行有标题和描述，这个在上面XAML代码中的数据模板可以看得出，查看该组件的ItemSource ，一起来看看它的代码是如何编写的：
public class SimpleModel : INotifyPropertyChanged
{
protected string itsName;
protected string itsDescription;
public event PropertyChangedEventHandler PropertyChanged;
public string Name
{
get { return this.itsName; }
set { this.itsName = value; NotifyPropertyChanged("Name"); }
}
public string Description
{
get { return this.itsDescription; }
set { this.itsDescription = value; NotifyPropertyChanged("Description"); }
}
protected void NotifyPropertyChanged(string thePropertyName)
{
if (this.PropertyChanged!=null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(thePropertyName));
}
}
}
{
protected string itsName;
protected string itsDescription;
public event PropertyChangedEventHandler PropertyChanged;
public string Name
{
get { return this.itsName; }
set { this.itsName = value; NotifyPropertyChanged("Name"); }
}
public string Description
{
get { return this.itsDescription; }
set { this.itsDescription = value; NotifyPropertyChanged("Description"); }
}
protected void NotifyPropertyChanged(string thePropertyName)
{
if (this.PropertyChanged!=null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(thePropertyName));
}
}
}
代码比较简单，封装了两个属性分别为他们注册PropertyChanged 事件响应数据变化。
而这个MODEL的数据来源于如下代码：
public class ListModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public ObservableCollection<SimpleModel> SimpleModels { get; private set; }
public bool IsDataLoaded { get; private set; }
public ListModel()
{
this.SimpleModels = new ObservableCollection<SimpleModel>();
}
/// <summary>
/// 加载数据
/// </summary>
public void LoadData()
{
for (int i = 1; i < 1000; i++)
{
this.SimpleModels.Add(new SimpleModel() { Name = "第" + i + "项", Description = "这是第" + i + "项数据" });
}
this.IsDataLoaded = true;
}
protected void NotifyPropertyChanged(string thePropertyName)
{
if (this.PropertyChanged!=null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(thePropertyName));
}
}
}
{
public event PropertyChangedEventHandler PropertyChanged;
public ObservableCollection<SimpleModel> SimpleModels { get; private set; }
public bool IsDataLoaded { get; private set; }
public ListModel()
{
this.SimpleModels = new ObservableCollection<SimpleModel>();
}
/// <summary>
/// 加载数据
/// </summary>
public void LoadData()
{
for (int i = 1; i < 1000; i++)
{
this.SimpleModels.Add(new SimpleModel() { Name = "第" + i + "项", Description = "这是第" + i + "项数据" });
}
this.IsDataLoaded = true;
}
protected void NotifyPropertyChanged(string thePropertyName)
{
if (this.PropertyChanged!=null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(thePropertyName));
}
}
}
代码跟上边的代码差不多，这里多了调用加载数据的方法LoadData（）为上面的每个Model赋值。而加载代码首先为其添加一个全局属性：
public static ListBoxWithCheckBox.ViewModel.ListModel viewModel = null;
//获取数据
public static ViewModel.ListModel ViewModel
{
get {
if (viewModel==null)
{
viewModel = new ViewModel.ListModel();
}
return viewModel;
}
}
//获取数据
public static ViewModel.ListModel ViewModel
{
get {
if (viewModel==null)
{
viewModel = new ViewModel.ListModel();
}
return viewModel;
}
}
转到MainPage的code behind 代码里面，在构造函数里面为DataContext 赋值，这里赋值的话上下文即可得到数据源，代码如下：
DataContext = App.ViewModel;
当应用程序导航进来时，调用加载全局属性去执行抓取数据的方法，代码如下：
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (!App.ViewModel.IsDataLoaded)
{
App.ViewModel.LoadData();
}
base.OnNavigatedTo(e);
}
{
if (!App.ViewModel.IsDataLoaded)
{
App.ViewModel.LoadData();
}
base.OnNavigatedTo(e);
}
最后的运行效果，我们选择第1 、2条数据做为欲删除的对象，然后删除看有啥变化？
点击删除后的效果：
mainPage 的code behind 完整代码如下：
完整代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using ListBoxWithCheckBox.ViewModel;
namespace ListBoxWithCheckBox
{
public partial class MainPage : PhoneApplicationPage
{
private ApplicationBar applicationBarChoose;
private ApplicationBarIconButton applicationBarIconButtonChoose;
private ApplicationBar applicationBarDeleteOrCancel;
private ApplicationBarIconButton applicationBarIconButtonDelete;
private ApplicationBarIconButton applicationBarIconButtonCancel;
// Constructor
public MainPage()
{
InitializeComponent();
ConstructApplicationBar();
DataContext = App.ViewModel;
this.Loaded += new RoutedEventHandler(MainPage_Loaded);
}
void MainPage_Loaded(object sender, RoutedEventArgs e)
{
}
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (!App.ViewModel.IsDataLoaded)
{
App.ViewModel.LoadData();
}
base.OnNavigatedTo(e);
}
/// <summary>
/// 构建应用程序条
/// </summary>
private void ConstructApplicationBar()
{
#region--应用程序条“选择”菜单--
this.applicationBarChoose = new ApplicationBar();
this.applicationBarIconButtonChoose = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Choose.png",UriKind.Relative));
this.applicationBarIconButtonChoose.Text = "选择";
this.applicationBarIconButtonChoose.Click += new EventHandler(applicationBarIconButtonChoose_Click);
this.applicationBarChoose.Buttons.Add(this.applicationBarIconButtonChoose);
this.applicationBarChoose.IsMenuEnabled = true;
this.applicationBarChoose.IsVisible = true;
this.ApplicationBar = this.applicationBarChoose;
#endregion
this.applicationBarDeleteOrCancel = new ApplicationBar();
#region --删除--
this.applicationBarIconButtonDelete = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Delete.png",UriKind.Relative));
this.applicationBarIconButtonDelete.Text = "删除";
this.applicationBarIconButtonDelete.Click += new EventHandler(applicationBarIconButtonDelete_Click);
#endregion
#region --取消--
this.applicationBarIconButtonCancel = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Cancel.png",UriKind.Relative));
this.applicationBarIconButtonCancel.Text = "取消";
this.applicationBarIconButtonCancel.Click += new EventHandler(applicationBarIconButtonCancel_Click);
#endregion
this.applicationBarDeleteOrCancel.Buttons.Add(this.applicationBarIconButtonDelete);
this.applicationBarDeleteOrCancel.Buttons.Add(this.applicationBarIconButtonCancel);
this.applicationBarDeleteOrCancel.IsMenuEnabled = true;
this.applicationBarDeleteOrCancel.IsVisible = true;
}
/// <summary>
/// listBox 为可选择状态
/// </summary>
private void SwitchToChooseState()
{
this.listBoxWithBoxes.IsInChooseState = true;
this.ApplicationBar = this.applicationBarDeleteOrCancel;
}
/// <summary>
/// listBox 为普通状态
/// </summary>
private void SwitchToNormalState()
{
this.listBoxWithBoxes.IsInChooseState = false;
this.ApplicationBar = this.applicationBarChoose;
}
/// <summary>
/// 取消操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonCancel_Click(object sender, EventArgs e)
{
SwitchToNormalState();
}
/// <summary>
/// 删除操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonDelete_Click(object sender, EventArgs e)
{
if (MessageBox.Show("你确定要删除选中项吗？","提示",MessageBoxButton.OKCancel)==MessageBoxResult.OK)
{
foreach (SimpleModel item in this.listBoxWithBoxes.SelectedItems)
{
App.ViewModel.SimpleModels.Remove(item);
}
SwitchToNormalState();
}
}
/// <summary>
/// 选择操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonChoose_Click(object sender, EventArgs e)
{
SwitchToChooseState();
}
}
}
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using ListBoxWithCheckBox.ViewModel;
namespace ListBoxWithCheckBox
{
public partial class MainPage : PhoneApplicationPage
{
private ApplicationBar applicationBarChoose;
private ApplicationBarIconButton applicationBarIconButtonChoose;
private ApplicationBar applicationBarDeleteOrCancel;
private ApplicationBarIconButton applicationBarIconButtonDelete;
private ApplicationBarIconButton applicationBarIconButtonCancel;
// Constructor
public MainPage()
{
InitializeComponent();
ConstructApplicationBar();
DataContext = App.ViewModel;
this.Loaded += new RoutedEventHandler(MainPage_Loaded);
}
void MainPage_Loaded(object sender, RoutedEventArgs e)
{
}
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (!App.ViewModel.IsDataLoaded)
{
App.ViewModel.LoadData();
}
base.OnNavigatedTo(e);
}
/// <summary>
/// 构建应用程序条
/// </summary>
private void ConstructApplicationBar()
{
#region--应用程序条“选择”菜单--
this.applicationBarChoose = new ApplicationBar();
this.applicationBarIconButtonChoose = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Choose.png",UriKind.Relative));
this.applicationBarIconButtonChoose.Text = "选择";
this.applicationBarIconButtonChoose.Click += new EventHandler(applicationBarIconButtonChoose_Click);
this.applicationBarChoose.Buttons.Add(this.applicationBarIconButtonChoose);
this.applicationBarChoose.IsMenuEnabled = true;
this.applicationBarChoose.IsVisible = true;
this.ApplicationBar = this.applicationBarChoose;
#endregion
this.applicationBarDeleteOrCancel = new ApplicationBar();
#region --删除--
this.applicationBarIconButtonDelete = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Delete.png",UriKind.Relative));
this.applicationBarIconButtonDelete.Text = "删除";
this.applicationBarIconButtonDelete.Click += new EventHandler(applicationBarIconButtonDelete_Click);
#endregion
#region --取消--
this.applicationBarIconButtonCancel = new ApplicationBarIconButton(new Uri("/content/ApplicationBar.Cancel.png",UriKind.Relative));
this.applicationBarIconButtonCancel.Text = "取消";
this.applicationBarIconButtonCancel.Click += new EventHandler(applicationBarIconButtonCancel_Click);
#endregion
this.applicationBarDeleteOrCancel.Buttons.Add(this.applicationBarIconButtonDelete);
this.applicationBarDeleteOrCancel.Buttons.Add(this.applicationBarIconButtonCancel);
this.applicationBarDeleteOrCancel.IsMenuEnabled = true;
this.applicationBarDeleteOrCancel.IsVisible = true;
}
/// <summary>
/// listBox 为可选择状态
/// </summary>
private void SwitchToChooseState()
{
this.listBoxWithBoxes.IsInChooseState = true;
this.ApplicationBar = this.applicationBarDeleteOrCancel;
}
/// <summary>
/// listBox 为普通状态
/// </summary>
private void SwitchToNormalState()
{
this.listBoxWithBoxes.IsInChooseState = false;
this.ApplicationBar = this.applicationBarChoose;
}
/// <summary>
/// 取消操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonCancel_Click(object sender, EventArgs e)
{
SwitchToNormalState();
}
/// <summary>
/// 删除操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonDelete_Click(object sender, EventArgs e)
{
if (MessageBox.Show("你确定要删除选中项吗？","提示",MessageBoxButton.OKCancel)==MessageBoxResult.OK)
{
foreach (SimpleModel item in this.listBoxWithBoxes.SelectedItems)
{
App.ViewModel.SimpleModels.Remove(item);
}
SwitchToNormalState();
}
}
/// <summary>
/// 选择操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void applicationBarIconButtonChoose_Click(object sender, EventArgs e)
{
SwitchToChooseState();
}
}
}
这里推荐一个小技巧，当我们编写动态数据时，又不想运行即想从代码IDE看到运行效果，类似于这样：
这个效果还是要借用PhoneApplicationPage 的DataContext属性，具体如下编写代码：
- 编写一个数据xaml命名为：ViewModelSampleData.xaml 文件，该文件负责为SimpleModels 做数据，代码如下：
<viewModels:ListModel
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:viewModels="clr-namespace:ListBoxWithCheckBox.ViewModel">
<viewModels:ListModel.SimpleModels>
<viewModels:SimpleModel Name="测试第一项" Description="这是测试的第一个节点" />
<viewModels:SimpleModel Name="测试第二项" Description="这是测试的第二个节点" />
</viewModels:ListModel.SimpleModels>
</viewModels:ListModel> - 在MainPage文件的XAML界面为DataContext赋值，代码如下：
d:DataContext="{d:DesignData ViewModelSampleData.xaml}"
Tip：该效果只运用于没有运行即可查看效果，运行后将会忽略。
怎么样，该组件不错吧，大家下载后试试吧。
源码下载：
