2
對於這個問題，我做了一個最小的項目，讓每個人都體驗這種行爲。我希望它不只是在我的引擎上運行這樣。列表框和複選框中的大量數據的奇怪行爲[最小項目提供]
在我的項目，我意識到一個列表框帶有很多樣本數據。列表框也有每個項目的複選框元素。
問題：首先我檢查/取消選中我的列表框中的複選框。然後我滾動幾次通過我的列表框。現在我注意到很多複選框會隨機選中/取消選中。如果我將ListBox減少一點（請參閱源代碼中的註釋），沒有奇怪的行爲。編輯::如果你沒有這個問題，請嘗試檢查列表最底部的項目。也許你必須用更多的對象來擴展列表才能看到問題。
這裏有一些代碼片段。正如你所看到的，我已經用List/ObservableCollection，PropertyChanged和LongListSelector代替Listbox來試用它。
C＃
// Already tried to use simple List<SampleCheckedData> buildings.
// Doesnt change anything.
private ObservableCollection<SampleCheckedData> buildings;
// Already tried with this as well.
/*protected ObservableCollection<SampleCheckedData> Buildings
{
get
{
return buildings;
}
set
{
buildings = value;
}
}*/
public MainPage()
{
InitializeComponent();
buildings = new ObservableCollection<SampleCheckedData>();
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Drizzle", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Snow", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Drizzle", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Snow", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Drizzle", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Snow", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Drizzle", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Snow", IsChecked = false });
// If you comment this data out, the listbox is smaller and no problem occurs in my case.
buildings.Add(new SampleCheckedData() { Name = "Cloudy" , IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Drizzle", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Snow", IsChecked = false });
// If you comment this data out, the listbox is smaller and no problem occurs in my case. [END]
this.listBox2.ItemsSource = buildings;
}
我選中/清除事件：
private void CheckBox_Checked(object sender, RoutedEventArgs e)
{
//Use this if you use the LongListSelector.
//ListBoxItem checedItem = this.listBox2.SelectedItem as ListBoxItem;
ListBoxItem checedItem = this.listBox2.ItemContainerGenerator.ContainerFromItem((sender as CheckBox).DataContext) as ListBoxItem;
if (checedItem != null)
{
checedItem.IsSelected = true;
}
}
private void CheckBox_Unchecked(object sender, RoutedEventArgs e)
{
//Use this if you use the LongListSelector.
//ListBoxItem checedItem = this.listBox2.SelectedItem as ListBoxItem;
ListBoxItem checedItem = this.listBox2.ItemContainerGenerator.ContainerFromItem((sender as CheckBox).DataContext) as ListBoxItem;
if (checedItem != null)
{
checedItem.IsSelected = false;
}
}
而且我smple數據類：
public class SampleCheckedData
{
//Already tried with this, but it is not working.
/*
private bool _isChecked;
public bool IsChecked
{
get { return _isChecked; }
set
{
if (_isChecked != value)
{
_isChecked = value;
NotifyPropertyChanged("IsChecked");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(String info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
*/
public bool IsChecked
{
get;
set;
}
public string Name
{
get;
set;
}
}
XAML
我的內容是這樣的：
<!--ContentPanel - zusätzliche Inhalte hier platzieren-->
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<ListBox x:Name="listBox2" SelectionMode="Multiple">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox IsChecked="{Binding IsChecked}" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked"/>
<TextBlock Text="{Binding Name}" Width="150" VerticalAlignment="Center"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<!--//Use this if you use the LongListSelector.-->
<!--<toolkit:LongListSelector x:Name="listBox2" Background="Transparent" IsFlatList="True" ItemTemplate="{StaticResource citiesItemTemplate}" />-->
</Grid>
可選，如果你想與LongListSelector嘗試它包括：
<DataTemplate x:Key="citiesItemTemplate">
<StackPanel Grid.Column="1" VerticalAlignment="Top">
<TextBlock Text="{Binding Name}" FontSize="26" Margin="12,-12,12,6"/>
<CheckBox IsChecked="{Binding IsChecked}" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked"/>
</StackPanel>
</DataTemplate>
而且xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
我希望有人能解決這個問題。沒有找到任何線索......
編輯：
相關的問題：
編輯：
我注意到，你必須添加一些鐵道部列表中的eobjects有這個問題：
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Sun", IsChecked = false });
buildings.Add(new SampleCheckedData() { Name = "Cloudy", IsChecked = false });
.....
然後，當您檢查列表頂部或底部的項目時，就會出現問題。
爲什麼你處理複選框檢查事件youself - 你不能使用雙向綁定？請參閱http://stackoverflow.com/questions/8642660/checkbox-two-way-binding-doesnt-work – Jay
我現在試過，但問題仍然存在。 –
我編輯了我的問題。我最小的例子中的列表似乎太短了。僅當您檢查最底部的項目並在此之後滾動時纔會出現問題。或者你可以用更多的對象擴展列表。 –