Backgorund
I am currently writing a program that allows a user to select a manufacture from a combo box. The combo box is created in wpf using the following wpf code segment:
<ComboBox Height="23" Margin="40.422,128.423,229.908,0" Name="itemProductManufacture" ToolTip="Click to open drop down menu" VerticalAlignment="Top" Text="Select A Manufacture" SelectionChanged="itemProductManufacture_SelectionChanged" DropDownOpened="itemProductManufacture_DropDownOpened">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ManufactureId}" Width="0"/>
<Image Name="itemManufactureImage" Source="{Binding ManufactureImage}" Height="15" Width="70" Stretch="Uniform"/>
<TextBlock Text="{Binding ManufactureName}"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
The data is provided form a database and each entry has a Image, a name and an Id (intentionally not shown)
Problem
I am trying to code the behaviour of the combo box so when it is open the image height is 50 and when it is closed it is 15 this is so the image is larger when it is first displayed and then smaller once selected so it doesn't take up too much space on the form.
I have tried editing the image propities using code but am unable to accsess it using its name or any other children of the combo box.
Thanks
Jonathan
As you are using data template you won't be able to access the directly by its name.
Try something like this -
Image image = this.itemProductManufacture.ItemTemplate.FindName("itemManufactureImage", this) as Image;
One thing I am not clear is whether you want to change image size for all the items or the selected one? If you need to access the image for a particulat item in combobox you may have to use the ItemContainerGenerator.ContainerFromItem, as explained in following posts -
WPF - ItemsControl - How do I get find my "CheckBox" item that is in the ItemTemplate?
http://www.sitechno.com/Blog/HowToUseAttachedPropertiesAsAnExtensionMechanismForACheckedListbox.aspx
look at this, To know the various ways of finding controls - How can I find WPF controls by name or type?
You can edit image properties from code using binding. Or you can use triggers in Datatemplate. When comboboxitems checked properties change, you can change height property of corresponding image
Try this:
<Image Height = "{Binding Path=IsDropDownOpen,
RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type ComboBox}},
Converter={StaticResource myBoolToHeightConverter}}" />
An example for Converter here
Related
I'm trying to highlight part of text in a textblock from a listbox datatemplate which in turn is bounded to a property of a custom class by using a textbox to search the list for input text. But the problem is that only part of the items are highlighting (most of the ones visible) but when i maximize the window and try to input another character then suddenly all of them gets highlighted my guess where the problem might be is in this piece of code:
ListBoxItem listboxItemFound= (ListBoxItem)this.listBox1.ItemContainerGenerator.ContainerFromItem(TItem);
Since this method is returning a null when the items are not visible but the items are currently in the listbox. Somehow I guess the items listboxItem instances are not yet created until you scroll down or maximize to view more items.
XAML DataTemplate:
<DataTemplate>
<Grid Name="gridOfListbox" Height="25" Margin="0,2">
<DockPanel Name="dockpanelWithTxtBlock">
<TextBlock Name="textbloxk" DockPanel.Dock="Left" FontSize="15" TextAlignment="Center">
<Run Text="" /><Run Background="Yellow" Text="" /><Run Text="{Binding ProductID}" />
</TextBlock>
</DockPanel>
</Grid>
</DataTemplate>
If more code is needed just let me know.
Any help would be greatly appreciated!!
Also if there is any other better way of finding the listboxItem bounded to the custom Item just let me know. Thank you very much!
[Pic of problem] http://i.stack.imgur.com/HViag.png
One way to fix this is to set VirtualizingStackPanel.IsVirtualizing to false for your ListBox. This will cause all of the items to be created right away. The downside to this is if your ListBox has many items, your program will use more memory (since more items will be created), and could potentially run slower depending on the number of items.
A better solution to consider would be to have multiple DataTemplates for this - one without the highlight, and one with. You can set a DataTemplateSelector for your ListBox (using the ItemTemplateSelector property). The selector can choose which template to use based on if the item matches the search term or not.
The tricky part would be writing the template with the highlighted text. You could probably achieve that by having properties on the object the ListBoxItem is bound to for the text before the highlighted text, the highlighted text, and then the remaining text.
I have a XAML ListBox where I am implementing an Image beside that a block of text is there. I want to display a count text in that image. For example for the first block in the image I want to display 1, for the 2nd block I want to display 2. This goes on. Below is the snippet. Can anybody please help me how can I write the count numbers in the image?
<StackPanel Grid.Column="0">
<Image Source="/Assets/Images/pin.png"></Image>
</StackPanel>
<TextBlock Name="locationID" Visibility="Collapsed" ></TextBlock>
</StackPanel>
</StackPanel>
If what you wanna do is display the index of each item of your datasource in your view, there are a couple of ways to do this.
You can save the item's index on a property of the datasource itself and bind that value in your view. This is probably the simplest solution if your collection is static. Cumbersome if dynamic, you would need to manually update the indexes of your collection changes.
You could expose the collection in the app level (making it global), write a converter and provide the item of the collection to it. Then you could search and return the index of that item in your global datasource.
You could implement a multibinding with the Cimbalino Toolkit providing both the item and the datasource and return the index.
here you go
<Grid Grid.Column="0">
<Grid.Background>
<ImageBrush ImageSource="/Assets/Images/pin.png"/>
</Grid.Background>
<TextBlock Text="text on image" Name="locationID" />
</Grid>
whole idea is to place the image as background of grid and place the text as content of the grid.
I have created a RadioButton style which I use across my application. The display part of which uses the content presenter to display whatever content I added to the button:
<ContentPresenter>
<ContentPresenter.ContentTemplate>
<DataTemplate>
<Grid>
<TextBlock Text="{TemplateBinding Content}" />
</Grid>
</DataTemplate>
</ContentPresenter.ContentTemplate>
</ContentPresenter>
I'm then attempting to bind a decimal with a string formatter to the styled button like so:
<RadioButton Content="{Binding Stake, StringFormat={}{0:C}}" Style="{DynamicResource NeutralSelectorButtonStyle}" />
Stake is a decimal within a ViewModel which is set as the DataContext. When I run this up the content coming through is blank.
I made a change using a label in the DataTemplate rather than a TextBlock, this displayed the decimal but had not formatted it.
Can anyone explain why this is happening and possibly provide a solution.
If you require any more information just ask :)
Thanks in advance.
You are almost there just instead of setting the string format inside binding you should use ContentStringFormat property when in ContentControls.
Take a look at this Label (it works with any content control):
<Label Content="{Binding Path=MaxLevelofInvestment}" ContentStringFormat="Amount is {0}"/>
ContentPresenter also has this property:
http://msdn.microsoft.com/en-us/library/system.windows.controls.contentpresenter.contentstringformat%28v=vs.110%29.aspx
Try it out. I hope it works for you.
I have a panorama control in which I have create a header template to add a list picker inside it. (Just like the peoples hub to select social accounts)
<DataTemplate x:Key="PanoramaItemHeaderTemplate">
<ContentPresenter>
<StackPanel Height="129">
<TextBlock Text="{Binding}" FontSize="72" Margin="0,7,0,0" />
<toolkit:ListPicker x:Name="listPick" Margin="0,-21,0,0" BorderThickness="0">
<toolkit:ListPickerItem Content="twitter"></toolkit:ListPickerItem>
</toolkit:ListPicker>
</StackPanel>
</ContentPresenter>
</DataTemplate>
The panorama control is inside the MainPage.xaml file and I want to have access to the listpicker from the code behind to be able to populate it, and handle it selection events.
I don't know how to do this. I tried adding the x:name property to the list picker I don't have access to it in the MainPage code behind.
Any idea on how to approach this is very welcomed, thanks!
From what you have now, the quickest way to do what you want is to traverse the visual tree
See here for the implementation:
How to access a specific item in a Listbox with DataTemplate?
You cannot access the ListPicker by x:Name because it is not unambiguous: there is a ListPicker generated for each PanoramaItem in your Panorama. So the first question is, is it really the think you want to do? If so you need to populate it using a binding (ItemSource)
You can access an element inside another resource, consider this example:
<Grid Name="myGrid">
<StackPanel x:Name="stack1">
<TextBlock x:Name="abc"/>
</StackPanel>
</Grid>
We can only access the Grid myGrid in code by default. To get reference to the StackPanel we can do this:
StackPanel myStack=myGrid.FindName("stack1") as Stackpanel;
After that we can get reference to the TextBlock:
TextBlock myTextBlock=myStack.FindName("abc") as TextBlock;
You can modify myTextBlock after that as you may like. You can apply the same technique in your case and it will work.
Hope that helps :).
I have a WPF textBox that is declared as ReadOnly
<TextBox IsReadOnly="True" IsTabStop="False" Width="200" />
So, User can not write anything into the TextBox or delete the content but it still allows user to drag the text from this textbox and drop it in any other textbox that caused the text removed from the first textbox(the read-only one) and thats unexpected. Is it a bug?
how can I get rid of this?
I tried the following code :
<StackPanel>
<TextBox IsReadOnly="True">Hello</TextBox>
<TextBox></TextBox>
</StackPanel>
When I drag-and-drop the text (after selection) from the first TexbtBox to the second one, the text is copied, but not removed from the first TextBox. I tried it under .NET 3.5 and .NET 4.0 targets.
If you want to get rid of your bug without trying to understand it (since it shouldn't happen), you can just put an empty control (Canvas will be ok) on top of your TextBox, with its Background property set to transparent.
<Grid>
<TextBox IsReadOnly="True" IsTabStop="False" Width="200" />
<Canvas Background="Transparent"/>
</Grid>
But the text won't be selectable anymore...