I want to have in my application a context menu "DefaultPrinter" which has some binded childs (another MenuItems) representing printer's names. Each child has a property IsCheckable set to true.
<MenuItem Header="DefaultPrinter" ItemsSource="{Binding AllPrinters}">
<MenuItem.ItemContainerStyle>
<Style TargetType="{x:Type MenuItem}">
<Setter Property="IsCheckable" Value="True"/>
</Style>
</MenuItem.ItemContainerStyle>
</MenuItem>
However, of course I want allow only one printer to be checked (this code doesn't suport that). I looked for solution in the Internet, but didn't find anything helpful.
The problem is that MenuItem derieves from ItemsControl and since that it has no concept of items selection (like Selector). I can try to write my own selection, but first, I would like to know is there better and simplier solution for achieving that goal.
Any help will be appreciated.
Could abuse a hidden RadioButton:
<MenuItem.ItemTemplate>
<DataTemplate>
<Grid>
<RadioButton GroupName="Printers"
IsChecked="{Binding IsChecked, RelativeSource={RelativeSource AncestorType=MenuItem}}"
Visibility="Collapsed"/>
<TextBlock Text="{Binding FullName}"/>
</Grid>
</DataTemplate>
</MenuItem.ItemTemplate>
Related
I'm having a weird problem with a simple ContextMenu using MahApps.Metro without any additional styling. When moving the cursor on top of the text or slightly around it, there is no problem. But when moving it further away, still inside the ContextMenu bounds, the Cursor is no longer on top of the MenuItem. Clicking now also doesn't result in any action at all besides closing the ContextMenu.
<ContextMenu ItemsSource="{Binding ContextItems}">
<ContextMenu.ItemTemplate>
<DataTemplate>
<MenuItem Header="{Binding Text}" Command="{Binding Command}"/>
</DataTemplate>
</ContextMenu.ItemTemplate>
</ContextMenu>
What am I doing wrong? Why doesn't the MenuItem use the available space?
If your ContextItems holds a collection with viewmodels then I think this could help you (not tested):
<ContextMenu ItemsSource="{Binding ContextItems}">
<ContextMenu.ItemContainerStyle>
<Style TargetType="MenuItem">
<Setter Property="Header" Value="{Binding Text}" />
<Setter Property="Command" Value="{Binding Command}" />
</Style>
</ContextMenu.ItemContainerStyle>
</ContextMenu>
Command and Text should be the properties on the viewmodel object.
I havent used MahApps.Metro . Though you can override the template like this
<ContextMenu.ItemTemplate>
<DataTemplate>
<MenuItem Header="{Binding Text}" Command="{Binding Command}"/>
<MenuItem.Template>
<ControlTemplate>
<ContentPresenter Content="{Binding Header,RelativeSource={RelativeSource TemplatedParent}}">
</ContentPresenter>
</ControlTemplate>
</MenuItem.Template>
</MenuItem>
</DataTemplate>
</ContextMenu.ItemTemplate>
I hope this will help.
Is it possible to hide a checkbox, but leave its content visible?
<ListBox
ItemsSource ="{Binding MyItemCollection}"
SelectionMode="Single"
Width="300"
Height="320">
<ListBox.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding IsChecked}">
<CheckBox.Content>
<TextBlock Text="{Binding Item.Code}"/>
</CheckBox.Content>
</CheckBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<StackPanel>
<CheckBox Content="Edit Mode"
IsChecked="{Binding Path=EditModeSelected, Mode=TwoWay}">
</CheckBox>
</StackPanel>
I would like to hide the checkboxes in the list box when I turn Edit Mode off (so it should be binded to EditModeSelected), but the text should be left visible.
In order to do so You can keep two TextBlocks. In edit mode visible CheckBox and hide TextBlock and in reader mode vice versa. I hope this may help. As DataTemplate can have only one child here's the fix
Create a Window Resource like below. Two Data Templates were created one for edit mode and another for Reader Mode.
<Window.Resources>
<DataTemplate x:Key="EditModeTemplate">
<CheckBox IsChecked="{Binding IsChecked}">
<CheckBox.Content>
<TextBlock Text="{Binding Item.Code}"/>
</CheckBox.Content>
</CheckBox>
</DataTemplate>
<DataTemplate x:Key="ReaderModeTemplate">
<TextBlock Text="{Binding Item.Code}"/>
</DataTemplate>
</Window.Resources>
Now in .cs file assign the Date Template as per requirements.
if (EditMode)
{
DemoCollection.ItemTemplate = this.Resources["EditModeTemplate"] as DataTemplate;
}
else
{
DemoCollection.ItemTemplate = this.Resources["ReaderModeTemplate"] as DataTemplate;
}
3 possible solutions come in my mind - two of them more or less "hacks" and one more or less clean solution:
A checkbox and textblock for every item - you can get problems with margins etc
A checkbox with no content (which is only visible when in edit mode), and a textblock which is always visible
Take the default controltemplate for checkbox (Default ControlTemplate for CheckBox) and bind the visibility of the checkbox
Here is a Xaml only solution pulled from a project I am working on. In this case "ShowCheck" is a field in the current binding context saying whether or not to show the check.
<CheckBox Content="{Binding Name}">
<CheckBox.Style>
<Style TargetType="CheckBox">
<Style.Triggers>
<DataTrigger Binding="{Binding ShowCheck}" Value="False">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="CheckBox">
<ContentControl Content="{TemplateBinding Content}"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</CheckBox.Style>
</CheckBox>
Basically if the checkbox should be invisible, then I use a style and a trigger to change the checkbox's template to something without the checkbox. My implementation the content is just a string, so this works. If you were putting more complicated objects into the checkbox, you might need to shuttle the ContentTemplate, ContentTemplateSelector, and related fields into the ContentControl that is used to replace the checkbox
Feel free to suggest an alternate approach to my problem if this isn't the best way to go about it.
I have a ToolBarTray and a TreeView. The tree has 2 items that are Concrete1 and Concrete2 classes respectively. I want the toolbar to have a different menu depending on which type of item is selected in the tree.
<ToolBarTray DockPanel.Dock="Top">
<ToolBar>
<ToolBar.Style>
<Style TargetType="{x:Type ToolBar}">
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=tree, Path=SelectedItem, Converter={StaticResource convert}}" Value="{x:Type root:Concrete1}">
<!--what do i do here??-->
</DataTrigger>
<DataTrigger Binding="{Binding ElementName=tree, Path=SelectedItem, Converter={StaticResource convert}}" Value="{x:Type root:Concrete2}">
<!--what do i do here??-->
</DataTrigger>
</Style.Triggers>
</Style>
</ToolBar.Style>
<ToolBar.Resources>
<Menu x:Key="awd">
<MenuItem Header="AWD"></MenuItem>
</Menu>
<Menu x:Key="dwa">
<MenuItem Header="DWA"></MenuItem>
</Menu>
</ToolBar.Resources>
</ToolBar>
</ToolBarTray>
<TreeView x:Name="tree" ItemsSource="{Binding Families}"></TreeView>
I've gotten as far as being able to set any regular property (background, etc) of the toolbar depending on which item is selected. I don't know how to proceed to add specific Menus to the toolbar.
I think I've figured it out. I've only done this with a ContextMenu and outside of a style trigger but I imagine it would be the same principle.
<TreeView>
<TreeView.ContextMenu>
<ContextMenu>
<StaticResourceExtension ResourceKey="myMenuItem"></StaticResourceExtension>
</ContextMenu>
</TreeView.ContextMenu>
</TreeView>
So I'm trying to alter some XAML code to add in a context menu that will change the number of decimal places of a value. My XAML is a little weak though and I'm getting a bit lost.
The code I have right now is:
<MenuItem Header="{DynamicResource DecimalPlaces}" ItemsSource="{Binding MenuItems}">
<ExclusiveMenuItem:ExclusiveMenuItem Header="{DynamicResource oneDecimal}" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
<ExclusiveMenuItem:ExclusiveMenuItem Header="{DynamicResource twoDecimal}" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
</MenuItem>
This will at least make the menu appear, but the problem is the DecimalPlaces handles ints (I've just put oneDecimal and twoDecimal in as placeholders for now) and I want the dynamic resource to be an int, preferably to go from one to ten too.
So my question is: how can I set the dynamic resource to an integer rather than a specific variable and is there a way to dynamically generate this menu (as opposed to writing 10 different entries), maybe based on an array or something?
Sorry if this is a pretty simple question, like I said, my XAML is a bit weak. Any help greatly appreciated.
If I understand your question correctly, I don't think a DynamicResource is what you need. A DynamicResource is a Resource that will get resolved at Runtime. This is usually used for theming.
It's a little hard to understand exactly what you're trying to do, but if you just want the header to display some text, just set it.
<MenuItem Header="{DynamicResource DecimalPlaces}" ItemsSource="{Binding MenuItems}">
<ExclusiveMenuItem:ExclusiveMenuItem Header="1" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
<ExclusiveMenuItem:ExclusiveMenuItem Header="2" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
<ExclusiveMenuItem:ExclusiveMenuItem Header="OneDecimal" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
<ExclusiveMenuItem:ExclusiveMenuItem Header="TwoDecimal" IsCheckable="True" IsChecked="{Binding Path=DecimalPlaces}"/>
</MenuItem>
If it needs some data coming from your MenuItems, then use an ItemTemplate or ItemContainerStyle.
<MenuItem Header="{DynamicResource DecimalPlaces}" ItemsSource="{Binding MenuItems}">
<MenuItem.ItemContainerStyle>
<Style TargetType="MenuItem">
<Setter Property="Header" Value="{Binding SomeProperty}" />
<Setter Property="IsCheckable" Value="True" />
<Setter Property="IsChecked" Value="{Binding Path=DecimalPlaces}" />
</Style>
</MenuItem.ItemContainerStyle>
</MenuItem>
I have an Expander control with its IsExpanded property bound to a bool in the mvvm model. The binding works fine until you dont touch the expander. Once you click the arrow in the expander to expand, the binding stops working. Setting the bool ShowPreview to false in the model doesn't collapse the expander.
<Expander Name="pExpander"
IsExpanded="{Binding Path=ShowPreview,Mode=OneWay}"
Header="Preview">
<TextBlock Text="{Binding Path=Message, Mode=OneWay}"></TextBlock>
</Expander>
If you remove Mode=OneWay does that fix the problem?
Upon reading your other CTQ (changes to the GUI do not affect the model), I don't have a good suggestion for how to limit the change being seen by the underlying data. What is the difference in:
myModel.MyProperty = true; // in *your* code behind
And
myModel.MyProperty = true; // done by a binding
What caught me out here is that IsExpanded is OneWay by default, so
<Style TargetType="TreeViewItem">
<Setter Property="IsExpanded" Value="{Binding Expanded}"/>
</Style>
doesn't work the way I expected. Only if you add Mode=TwoWay, then it works (i.e. the item starts paying attention to my Expanded property, and updating it), as in
<Style TargetType="TreeViewItem">
<Setter Property="IsExpanded" Value="{Binding Expanded, Mode=TwoWay}"/>
</Style>
With Silverlight I do this:
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:ei="http://schemas.microsoft.com/expression/2010/interactions"
<Expander Name="pExpander" IsExpanded="True" Header="Preview">
<i:Interaction.Triggers>
<ei:PropertyChangedTrigger Binding="{Binding ShowPreview, Mode=OneWay}">
<ei:ChangePropertyAction PropertyName="IsExpanded" Value="{Binding ShowPreview, Mode=OneWay}"/>
</ei:PropertyChangedTrigger>
</i:Interaction.Triggers>
<TextBlock Text="{Binding Path=Message, Mode=OneWay}"></TextBlock>
</Expander>
<Expander Name="pExpander1" IsExpanded="True" Header="Preview 1">
<i:Interaction.Triggers>
<ei:PropertyChangedTrigger Binding="{Binding ShowPreview, Mode=OneWay}">
<ei:ChangePropertyAction PropertyName="IsExpanded" Value="{Binding ShowPreview, Mode=OneWay}"/>
</ei:PropertyChangedTrigger>
</i:Interaction.Triggers>
<TextBlock Text="{Binding Path=Message1, Mode=OneWay}"></TextBlock>
</Expander>
//...
The binding is not lost when you manualy expand/collapse one Expander...
Do three things,
Make sure your ViewModel is implementing INotifyPropertyChanged. Your ui wont know about the change if your view model doesnt inform it when the property changes
Change the Mode to TwoWay, you want your view model updated when the expander changes and you want your expander updated when the view model changes
Lastly if the above two don't work use a debug converter to ascertain if your binding is failing. there is an example here of how to do this. This is a technique every wpf developer needs.
I know there was an issue with radio buttons that they would lose their bindings when another button in the group was set, i don't think that is the issue here, however a debug converter will help you figure this out.