我正在开发一个WPF应用程序，我必须在ListViews容器内绑定三个不同的GroupBox。
这是显示的XAML：
<GroupBox Header="Zone2 Sensors" Height="250" Name="grpBoxZone2" Width="380" Margin="25,248,90,660" Grid.Column="5" Grid.ColumnSpan="2" Foreground="#FF1E5EE6">
<Grid Height="250" Width="375" MinHeight="250">
<Label Content="Strain" Width="40" Name="labelZone2S" Foreground="#FF1E5EE6" Margin="44,1,291,227" />
<Label Content="Accelerometer" Width="79" Name="labelZone2A" Foreground="#FF1E5EE6" Margin="132,1,164,227" />
<Label Content="Tilt" Name="labelZone2T" Foreground="#FF1E5EE6" Margin="264,1,82,227" />
<ListView Margin="25,42,268,49" Name="lst2" ItemsSource="{Binding}" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" BorderThickness="0" SelectionChanged="lst2_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<Border Padding="5" Background="#FF83A2DA" BorderThickness="1" BorderBrush="Black">
<CheckBox Name="CheckBoxs1" IsChecked="{Binding IsSelected}" Click="CheckBoxs1_Click" Unchecked="CheckBoxs1_Unchecked">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ObjectData}"></TextBlock>
</StackPanel>
</CheckBox>
</Border>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView Margin="134,42,159,111" Name="lstZone2A" ItemsSource="{Binding}" HorizontalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" BorderThickness="0" SelectionChanged="lstZone2A_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<Border Padding="5" Background="#FF83A2DA" BorderThickness="1" BorderBrush="Black">
<CheckBox Name="ChkZone2A" IsChecked="{Binding IsSelected}" Checked="ChkZone2A_Checked" Unchecked="ChkZone2A_Unchecked">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ObjectData}"></TextBlock>
</StackPanel>
</CheckBox>
</Border>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView Margin="249,42,44,156" Name="lstZone2T" ItemsSource="{Binding}" HorizontalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" BorderThickness="0" SelectionChanged="lstZone2T_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<Border Padding="5" Background="#FF83A2DA" BorderThickness="1" BorderBrush="Black">
<CheckBox Name="ChkZone2T" IsChecked="{Binding IsSelected}" Checked="ChkZone2T_Checked" Unchecked="ChkZone2T_Unchecked">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ObjectData}"></TextBlock>
</StackPanel>
</CheckBox>
</Border>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<CheckBox Content="Select ALL Sensors" Margin="14,21,248,213" Name="chkZone2SelectAll" Checked="chkZone2SelectAll_Checked" Unchecked="chkZone2SelectAll_Unchecked" />
</Grid>
</GroupBox>
这是我用来检查和取消选中项目的C＃代码：
private void chkZone2SelectAll_Checked(object sender, RoutedEventArgs e)
{
try
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < lst2.Items.Count; i++)
{
// Get a all list items from listbox
ListBoxItem ListBoxItemObj = (ListBoxItem)lst2.ItemContainerGenerator.ContainerFromItem(lst2.Items[i]);
//bool check = ListBoxItemObj.HasContent;
// find a ContentPresenter of that list item.. [Call FindVisualChild Method]
ContentPresenter ContentPresenterObj = FindVisualChild<ContentPresenter>(ListBoxItemObj);
// call FindName on the DataTemplate of that ContentPresenter
DataTemplate DataTemplateObj = ContentPresenterObj.ContentTemplate;
CheckBox Chk = (CheckBox)DataTemplateObj.FindName("CheckBoxs1", ContentPresenterObj);
Chk.IsChecked = true;
}
for (int i = 0; i < lstZone2A.Items.Count; i++)
{
// Get a all list items from listbox
ListBoxItem ListBoxItemObj = (ListBoxItem)lstZone2A.ItemContainerGenerator.ContainerFromItem(lstZone2A.Items[i]);
// find a ContentPresenter of that list item.. [Call FindVisualChild Method]
ContentPresenter ContentPresenterObj = FindVisualChild<ContentPresenter>(ListBoxItemObj);
// call FindName on the DataTemplate of that ContentPresenter
DataTemplate DataTemplateObj = ContentPresenterObj.ContentTemplate;
CheckBox Chk = (CheckBox)DataTemplateObj.FindName("ChkZone2A", ContentPresenterObj);
Chk.IsChecked = true;
}
for (int i = 0; i < lstZone2T.Items.Count; i++)
{
// Get a all list items from listbox
ListBoxItem ListBoxItemObj = (ListBoxItem)lstZone2T.ItemContainerGenerator.ContainerFromItem(lstZone2T.Items[i]);
// find a ContentPresenter of that list item.. [Call FindVisualChild Method]
ContentPresenter ContentPresenterObj = FindVisualChild<ContentPresenter>(ListBoxItemObj);
// call FindName on the DataTemplate of that ContentPresenter
DataTemplate DataTemplateObj = ContentPresenterObj.ContentTemplate;
CheckBox Chk = (CheckBox)DataTemplateObj.FindName("ChkZone2T", ContentPresenterObj);
Chk.IsChecked = true;
}
foreach (TripInfo cbObject in lst2.Items)
{
cbObject.IsSelected = true;
}
foreach (TripInfo cbObject in lstZone2A.Items)
{
cbObject.IsSelected = true;
}
foreach (TripInfo cbObject in lstZone2T.Items)
{
cbObject.IsSelected = true;
}
foreach (TripInfo cbObject in lst2.Items)
{
if (cbObject.IsSelected)
{
if (SelectedSensser != null)
{
if (SelectedSensser.Contains(cbObject.ObjectData.ToString())) { }
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
}
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
SelectedSensser += sb.ToString().Trim();
sb.Clear();
}
}
foreach (TripInfo cbObject in lstZone2A.Items)
{
if (cbObject.IsSelected)
{
if (SelectedSensser != null)
{
if (SelectedSensser.Contains(cbObject.ObjectData.ToString())) { }
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
}
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
SelectedSensser += sb.ToString().Trim();
sb.Clear();
}
}
foreach (TripInfo cbObject in lstZone2T.Items)
{
if (cbObject.IsSelected)
{
if (SelectedSensser != null)
{
if (SelectedSensser.Contains(cbObject.ObjectData.ToString())) { }
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
}
else
{
sb.AppendFormat("{0}, ", cbObject.ObjectData.ToString());
}
SelectedSensser += sb.ToString().Trim();
sb.Clear();
}
}
}
catch (Exception ex) { throw ex; }
}
private ChildControl FindVisualChild<ChildControl>(DependencyObject DependencyObj) where ChildControl : DependencyObject
{
int count = VisualTreeHelper.GetChildrenCount(DependencyObj);
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(DependencyObj); i++)
{
DependencyObject Child = VisualTreeHelper.GetChild(DependencyObj, i);
if (Child != null && Child is ChildControl)
{
return (ChildControl)Child;
}
else
{
ChildControl ChildOfChild = FindVisualChild<ChildControl>(Child);
if (ChildOfChild != null)
{
return ChildOfChild;
}
}
}
return null;
}
public class TripInfo
{
public TripInfo(string objectData) { ObjectData = objectData; }
public TripInfo(bool isSelected, string objectData)
{
IsSelected = isSelected;
ObjectData = objectData;
}
public Boolean IsSelected
{ get; set; }
public String ObjectData
{ get; set; }
}
但是，当它到达第8个索引时，这会给我以下错误，但ListItems计数显示10个元素：
Value cannot be null.
Parameter name: element
答案 0 :(得分：0)
感谢所有刚访问此问题的人。我找到了解决方案。这有点棘手 :-)。列在垂直滚动下的列表项，或者你可以说FindVisualChild类找不到那些不可见的项目。当我增加listview的高度和找到的所有项目时。
答案 1 :(得分：0)
我发现您正在使用Binding和Templates来显示您的数据
您可以轻松地在视图模型上调用ICommand并将所有项目设置为IsSelected=True。如果你已经正确实现了INotifyPropertyChanged它应该可以工作，你就不再需要代码隐藏/ FindVisual了。