How to add new setter programatically in existing ItemContainerStyle in WPF? - wpf

Question

I have item container style for list view like below :
<ListView.ItemContainerStyle>
<Style>
<Setter Property="Padding" Value="0"></Setter>
<Setter Property="Margin" Value="0,0,0,-1"></Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=EventType}" Value="2">
<Setter Property="Background" Value="Green"/>
<Setter Property="Foreground" Value="White"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ListView.ItemContainerStyle>
Now I need to add new setter for context menu programatically based on item data. How can I do it ?
Please guide me.....
Thanks

Answer 1

I have to display Images dynamically and show/hide depends on state of checkboxes using Style and DataTrigger.
<Image Source="/WpfApplication;component/Imgs/img1_1.png">
<Image.Style>
<Style>
<Setter Property="Image.Visibility" Value="Collapsed"></Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=isDisplayingImgSet1, Path=IsChecked}" Value="True">
<Setter Property="Image.Visibility" Value="Visible"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Image.Style>
After spec modification i have to create checkboxes dynamically, then to set Style.
At beginning, I have the same error message.
Image img = new Image();
//..
img.Style.Setters.Add(setter);
img.Style.Triggers.Add(trigger);
//..After a 'SetterBaseCollection' is in use (sealed), it cannot be modified.
The solution is to create a style object and Affect it to Image.Style
//Visibility
DataTrigger trigger = new DataTrigger();
trigger.Binding = new Binding
{
ElementName = "isDisplayingImgSet"+NumSet,
Path = new PropertyPath(CheckBox.IsCheckedProperty)
};
trigger.Value = "True";
trigger.Setters.Add(new Setter(ContentControl.VisibilityProperty, Visibility.Visible));
Setter setter = new Setter(ContentControl.VisibilityProperty, Visibility.Collapsed);
Style style = new Style(typeof(Image));
style.Setters.Add(setter);
style.Triggers.Add(trigger);
img.Style = style;
Hope that helping you
PS : It's my first post

Answer 2

I have implemented logic to add setter dynamically in existing style like below :
listview1.ItemContainerStyle.Setters.Add(new Setter(Control.ContextMenuProperty,GetItemContextMenu(txtName.Text)));
But it gives me following error :
"After a 'SetterBaseCollection' is in use (sealed), it cannot be modified."
I think it is not possible to add new setter in sealed style. So I have got another temporary solution like assign context menu to whole listview rather than it's item on preview mouse right click event. So context menu will be same for all items then managed in coding based on data of selected item.

Answer 3

<ListView.ItemContainerStyle>
<Style>
<Setter Property="Padding" Value="0"></Setter>
<Setter Property="Margin" Value="0,0,0,-1"></Setter>
<Setter Property="ContextMenu">
<Setter.Value>
<ContextMenu/>
</Setter.Value>
</Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=EventType}" Value="2">
<Setter Property="Background" Value="Green"/>
<Setter Property="Foreground" Value="White"></Setter>
<Setter Property="ContextMenu">
<Setter.Value>
<ContextMenu/>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ListView.ItemContainerStyle>

Answer 4

If you create a new Style() and "re-add" the the setters, you can get around this issue if you are using Telerik.
private static void AddColumnSetter(GridViewColumn gridColumn, SetterBase setter)
{
var setters = new SetterBaseCollection();
if (gridColumn.CellStyle != null)
{
foreach (SetterBase setterBase in gridColumn.CellStyle.Setters)
{
setters.Add(setterBase);
}
}
setters.Add(setter);
gridColumn.CellStyle = new Style();
foreach (var setr in setters)
{
gridColumn.CellStyle.Setters.Add(setr);
}
}