I have a list picker when clicking on the control to select another item it seems to look like it is going to work but is all white I can sometimes get it to select another item but cant see what is selected until you are off of it. This is how I have it set up. When I set it to full mode the name space is the only thing that shows not the actual name of the item. All I am trying to do is upon loading the view I need to load the listPicker with values.
<phone:PhoneApplicationPage.Resources>
<DataTemplate x:Name="PickerItemTemplate" >
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding TankTypeName}" Style="{StaticResource PhoneTextNormalStyle}"/>
</StackPanel>
</DataTemplate>
<DataTemplate x:Name="PickerFullModeItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding TankTypeName}" Style="{StaticResource PhoneTextNormalStyle}" FontFamily="{StaticResource PhoneFontFamilyLight}"/>
</StackPanel>
</DataTemplate>
</phone:PhoneApplicationPage.Resources>
<!--ContentPanel - place additional content here-->
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<TextBox Height="72" HorizontalAlignment="Left" Margin="0,50,0,0" Name="TextBoxProjectName" Text="" VerticalAlignment="Top" Width="456" />
<TextBlock Height="30" HorizontalAlignment="Left" Margin="12,28,0,0" Name="TextBlockProjectName" Text="Tank Name:" VerticalAlignment="Top" />
<toolkit:ListPicker Header="Tank Type:" ItemsSource="{Binding TankTypes}"
ItemTemplate="{StaticResource PickerItemTemplate}"
FullModeItemTemplate="{Binding PickerFullModeItemTemplate}"
SelectedItems="{Binding SelectedTankTypes,Mode=TwoWay}"
Height="100" HorizontalAlignment="Left"
Margin="6,144,0,0" Name="ListPickerTankType"
VerticalAlignment="Top" Width="444" >
</toolkit:ListPicker>
</Grid>
View Model
private List<TankType> _tankType;
private ObservableCollection<Object> _selectedTankType= new ObservableCollection<object>();
/// <summary>
/// Collection of Tank Type objects.
/// </summary>
public List<TankType> TankTypes
{
get
{
return _tankType;
}
set
{
if (value != _tankType)
{
_tankType = value;
NotifyPropertyChanged("TankType");
}
}
}
public ObservableCollection<object> SelectedTankTypes
{
get
{
return _selectedTankType;
}
set
{
if (_selectedTankType == value)
{
return;
}
_selectedTankType = value;
NotifyPropertyChanged("SelectedTankTypes");
}
}
This is a edit page so in the constructor of the view.
public TaskDetail()
{
InitializeComponent();
var tankTypeViewModel = new ViewModels.TankVewModel();
tankTypeViewModel.GetTankTypes();
ListPickerTankType.DataContext = tankTypeViewModel;
}
Revised OK I removed the height on the listpicker and now can see it made it bigger so the three items are there. I just cant seem to change the font color to black so I can see it when you click on the listpicker.
Figured it out. I needed to remove the height and set the foreground color to black.
Related
I'm very new to WPF and currently learning the concepts of data binding.
my simplified XAML code. besides my problem (below) it works fine - quick and dirty placing of objects via GUI, will be cleaned up once works:
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="60"/>
<RowDefinition/>
<RowDefinition Height="40"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0">
</Grid>
<Grid Grid.Row="1">
<GroupBox Header="Change Type:" Height="95" Width="100" VerticalAlignment="Top" Margin="270,4,422,0" >
<StackPanel>
<RadioButton x:Name="RbtAdd" HorizontalAlignment="Left" Margin="5" VerticalAlignment="Top" GroupName="modGroup" Checked="ModeRadio_Checked">
<WrapPanel>
<TextBlock Text="Add" Foreground="Green"/>
</WrapPanel>
</RadioButton>
<RadioButton x:Name="RbtPull" HorizontalAlignment="Left" Margin="5" VerticalAlignment="Top" GroupName="modGroup" Checked="ModeRadio_Checked">
<WrapPanel>
<TextBlock Text="Pull" Foreground="Blue"/>
</WrapPanel>
</RadioButton>
<RadioButton x:Name="RbtModify" HorizontalAlignment="Left" Margin="5" VerticalAlignment="Top" GroupName="modGroup" Checked="ModeRadio_Checked">
<WrapPanel>
<TextBlock Text="Modify" Foreground="DarkGray"/>
</WrapPanel>
</RadioButton>
</StackPanel>
</GroupBox>
<TextBlock x:Name="txtCurStock" HorizontalAlignment="Left" Margin="330,181,0,0" TextWrapping="Wrap" Text="{Binding Path=CurrentStock}" VerticalAlignment="Top" FontSize="20" FontWeight="Bold" TextAlignment="Center"/>
<Label Content="Current stock:" HorizontalAlignment="Left" Margin="289,156,0,0" VerticalAlignment="Top"/>
<Label x:Name ="lblOperation" Content="Stock to Pull:" HorizontalAlignment="Left" Margin="507,156,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="txtEntry" HorizontalAlignment="Left" Height="32" Margin="489,181,0,0" TextWrapping="Wrap" TextAlignment="Center" Text="{Binding Path=ModEntry}" VerticalAlignment="Top" Width="120" FontSize="20" FontWeight="Bold" TextChanged="TxtEntry_TextChanged"/>
<Label Content="New Stock" HorizontalAlignment="Right" Margin="714,156,0,0" VerticalAlignment="Top" Width="68"/>
<TextBlock Text="{Binding Path=NewStock}" HorizontalAlignment="Right" Margin="0,186,10,0" TextAlignment="Center" TextWrapping="Wrap" VerticalAlignment="Top" FontSize="20" FontWeight="Bold" Width="68"/>
<TextBox x:Name="txtComment" HorizontalAlignment="Left" Height="86" Margin="289,233,0,0" TextWrapping="Wrap" Text="{Binding Path=ModEntry}" VerticalAlignment="Top" Width="493"/>
<Label Content="Comment:" HorizontalAlignment="Left" Margin="289,207,0,0" VerticalAlignment="Top"/>
<TextBlock x:Name ="txtModindicator" HorizontalAlignment="Left" Margin="433,181,0,0" TextWrapping="Wrap" Text="-" FontSize="20" FontWeight="Bold" VerticalAlignment="Top"/>
<TextBlock x:Name ="txtResindicator" HorizontalAlignment="Left" Margin="663,182,0,0" TextWrapping="Wrap" Text="=" FontSize="20" FontWeight="Bold" VerticalAlignment="Top"/>
</Grid>
</Grid>
now the shortened c# code:
using System.Windows;
using System.Windows.Controls;
using System.ComponentModel;
using System.Runtime.CompilerServices;
namespace SomeWPF
{
/// <summary>
/// Interaction logic for ModifyWindow.xaml
/// </summary>
public partial class MainWindow : INotifyPropertyChanged
{
public enum Mymode
{
add,
pull,
modify
}
public Mymode mode;
public MainWindow()
{
DataContext = this;
InitializeComponent();
CurrentStock = 5;
RbtPull.IsChecked = true;
ModEntry = 1;
}
private void ModeRadio_Checked(object sender, RoutedEventArgs e)
{
if (sender != null)
{
if (sender.Equals(RbtAdd))
{
mode = Mymode.add;
txtModindicator.Text = "+";
txtComment.Text = "Add";
lblOperation.Content = "Stock to Add:";
}
else if (sender.Equals(RbtPull))
{
mode = Mymode.pull;
txtModindicator.Text = "-";
txtComment.Text = "Pull";
lblOperation.Content = "Stock to Pull:";
}
else
{
mode = Mymode.modify;
txtModindicator.Text = "~";
lblOperation.Content = "Corrected Quantity:";
txtComment.Text = "Mod";
}
TxtEntry_TextChanged(sender, null);
}
}
private void TxtEntry_TextChanged(object sender, TextChangedEventArgs e)
{
if (mode == Mymode.add)
{
NewStock = CurrentStock + ModEntry;
}
else if (mode == Mymode.pull)
{
NewStock = CurrentStock - ModEntry;
}
else
{
NewStock = ModEntry;
}
}
#region Binding Stuff
private int _newstock;
public int NewStock
{
get
{
return _newstock;
}
set
{
if (_newstock != value)
{
_newstock = value;
OnPropertyChanged();
}
}
}
private int _modentry;
public int ModEntry
{
get
{
return _modentry;
}
set
{
if (_modentry != value)
{
_modentry = value;
OnPropertyChanged();
}
}
}
private int _currentstock;
public int CurrentStock
{
get
{
return _currentstock;
}
set
{
if (_currentstock != value)
{
_currentstock = value;
OnPropertyChanged();
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
#endregion
}
}
So this window is a popup in a little program for an inventory storage for the users to enter movements of the inventory.
everything loads fine so far and I now wanted to do the quite simple calculation part. with "old" winforms c# you'd just take the values and update the text property of the result "manually" but of course we (I) want to learn new stuff and do stuff with data binding.
The code also does the calculation, but the trigger is somehow not what I want.
let's say current stock is 5
when window loads, the mode is set to Pull (RbtPull) and the user entry (Binding to ModEntry) is set to 1 via code. The NewStock therefore should be 4 which displays correctly. (yey)
Also the comment field (for debugging for now) displays the ModEntry value 1.
so far so good.
Now I enter 3 in the Stock to Pull field, but nothing happens. (I want it to react "realtime"). The new Stock is still displayed as 4, the comment is still displayed as 1.
When I leave the field (and click into the comment field) - the property change is detected and the Comment Field shows also 3 (=ModEntry) - so it's not "realtime" but only triggers when the field is losing focus, but that would be also acceptable.
The real problem is: The new Stock stays 4 and does not calculate.
Now when I enter the Stock to Pull field again and change the value to let's say 5, the New Stock field updates to 2 (so to the value I entered before 5-3=2)
Overwriting the field with again 5 will change the new Stock to 0.
So it's always "one step behind".
From what I have found i have an idea, that I need some kind of Binding Converter instead of my method of calculating things, but I can't really find anything suitable and am not familiar enough yet with data binding. Have tried out some things already directly in the binding variable code but none worked. If anyone could hint me in the right direction I'd be very thankful. (don't need a silver plate solution but just an idea what way to search (e.g. if the sort of binding I use makes sense at all or if there's something I have to add etc.).
Thanks a lot!
PS: of course if someone is motivated to give a silver plate solution I'd also be grateful. :) - and sorry for the bad english, no native speaker.
#nosale 's second link (see comments) provided the answer to the Problem.
Setting both XAML fields txtEntry and the Result field to UpdateSourceTrigger=PropertyChanged solved the issue.
so the correct block Looks like this now without changes to the c# code:
<Label Content="Current stock:" HorizontalAlignment="Left" Margin="289,156,0,0" VerticalAlignment="Top"/>
<Label x:Name ="lblOperation" Content="Stock to Pull:" HorizontalAlignment="Left" Margin="507,156,0,0" VerticalAlignment="Top"/>
<TextBox x:Name="txtEntry" HorizontalAlignment="Left" Height="32" Margin="489,181,0,0" TextWrapping="Wrap" TextAlignment="Center" Text="{Binding Path=ModEntry, UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Top" Width="120" FontSize="20" FontWeight="Bold" TextChanged="TxtEntry_TextChanged"/>
<Label Content="New Stock" HorizontalAlignment="Right" Margin="714,156,0,0" VerticalAlignment="Top" Width="68"/>
<TextBlock Text="{Binding Path=NewStock, UpdateSourceTrigger=PropertyChanged}" HorizontalAlignment="Right" Margin="0,186,10,0" TextAlignment="Center" TextWrapping="Wrap" VerticalAlignment="Top" FontSize="20" FontWeight="Bold" Width="68"/>
<TextBox x:Name="txtComment" HorizontalAlignment="Left" Height="86" Margin="289,233,0,0" TextWrapping="Wrap" Text="{Binding Path=ModEntry}" VerticalAlignment="Top" Width="493"/>
<Label Content="Comment:" HorizontalAlignment="Left" Margin="289,207,0,0" VerticalAlignment="Top"/>
Reason is, that textboxes have a Default UpdateSourceTrigger=LostFocus and not PropertyChanged to prevent updates with user having entered typos.
something new learned: WPF is cool and automatically handles non plausible values like null or strings and marks the field red! :)
thanks again for the links!
In UWP C#, I have one ListView in upper row & another in lower row. When I drag a listitem from upper ListView & drop it on lower ListView, I am getting the source. But, I am unable to get the destination. ie) the listview item/(Folder object in my case) where I dropped.
<ListView Name="ListviewCars"
CanDragItems="True" DragItemsStarting="ListviewCars_DragItemsStarting"
SelectionMode="Single" IsItemClickEnabled="True"
DataContext="Cars" ItemsSource="{Binding CarsCollection}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Background="Transparent" Height="80" Orientation="Horizontal"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate >
<DataTemplate>
<Grid Name="GrdCars" >
<Grid Height="80" Width="90" Padding="5">
<Grid.Background>
<ImageBrush Stretch="Uniform" ImageSource="Assets/car.png"/>
</Grid.Background>
<TextBlock Text="{Binding Name}" FontWeight="Bold" TextWrapping="Wrap" TextAlignment="Center"
HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView Name="GrdViewImg" ScrollViewer.VerticalScrollBarVisibility="Disabled"
AllowDrop="True" DragOver="Image_DragOver"
Drop="Image_OnDrop"
DataContext="Folders" ItemsSource="{Binding FolderCollection}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Background="Transparent" Height="80" Orientation="Horizontal" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate >
<DataTemplate>
<Grid Name="GrdForFolderMenu" RightTapped="GrdForFolderMenu_RightTapped">
<Grid Height="80" Width="90" Padding="5">
<Grid.Background>
<ImageBrush Stretch="UniformToFill" ImageSource="Assets/Folderimage.png"/>
</Grid.Background>
<TextBlock Text="{Binding Name}" FontWeight="Bold" TextWrapping="Wrap" TextAlignment="Center" HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
I have found a simple solution myself. I get the source from DragItemsStarting event of the SoureListView. and target item (as mentioned by ashchuk) from a Grid placed inside Datatemplate of Target ListView. as shown below. Everything works fine now!
(Cars is my Source custom list item. Folders is my Target custom list item)
private void SoureListView_DragItemsStarting(object sender, DragItemsStartingEventArgs e)
{
Cars x = e.Items[0] as Cars;
string DraggedSourceCar = x.Name;
e.Data.Properties.Add("myArgs", DraggedSourceCar);
}
private void GridInsideDatatemplateOfTargetListview_Drop(object sender, DragEventArgs e)
{
var x = sender as Grid;
var y = x.DataContext as Folders;
string toMoveFolderName = y.Name;
string DraggedSourceCar = e.DataView.Properties["myArgs"].ToString();
Debug.WriteLine(DraggedSourceCar + Environment.NewLine + toMoveFolderName );
}
private void TargetListview_DragOver(object sender, DragEventArgs e)
{
e.AcceptedOperation = DataPackageOperation.Copy;
}
You have to find out by yourself = DragEventArgs.GetPosition() in the destination drop, then the underlying item with smoe helper functions
public static object GetObjectAtPoint<ItemContainer>(this ItemsControl control, Point p)
where ItemContainer : DependencyObject
{
// ItemContainer - can be ListViewItem, or TreeViewItem and so on(depends on control)
ItemContainer obj = GetContainerAtPoint<ItemContainer>(control, p);
if (obj == null)
return null;
return control.ItemContainerGenerator.ItemFromContainer(obj);
}
public static ItemContainer GetContainerAtPoint<ItemContainer>(this ItemsControl control, Point p)
where ItemContainer : DependencyObject
{
HitTestResult result = VisualTreeHelper.HitTest(control, p);
if (result != null)
{
DependencyObject obj = result.VisualHit;
while (VisualTreeHelper.GetParent(obj) != null && !(obj is ItemContainer))
{
obj = VisualTreeHelper.GetParent(obj);
}
// Will return null if not found
return obj as ItemContainer;
}
else return null;
}
Did you checked this sample?
After some research I found what DragEventArgs contains an OriginalSource property with Name matches the name of target list when Drop event invoked.
I'm not checked it with folders and subfolders, but maybe OriginalSource will contain folder where item dropped.
<TextBlock Grid.Row="1" Margin="8,4"
VerticalAlignment="Bottom"
Text="All Items"/>
<ListView x:Name="SourceListView"
Grid.Row="2" Margin="8,4"
SelectionMode="Extended"
CanDragItems="True"
DragItemsStarting="SourceListView_DragItemsStarting"/>
<TextBlock Grid.Row="1" Grid.Column="1" Margin="8,4"
VerticalAlignment="Bottom"
Text="Selection"/>
<ListView x:Name="TargetListView"
Grid.Row="2" Grid.Column="1" Margin="8,4"
AllowDrop="True" CanReorderItems="True" CanDragItems="True"
DragOver="TargetListView_DragOver"
Drop="TargetListView_Drop"
DragItemsStarting="TargetListView_DragItemsStarting"
DragItemsCompleted="TargetListView_DragItemsCompleted"/>
And here is printscreen with fired breakpoint:
EDIT:
To get an item inside of TargetList you can do a trick.
I think you use DataTemplate to display custom list items ("folders"). You can see a sample below. As you see I add Grid_DragOver trigger.
<Page.Resources>
<DataTemplate x:Key="ListViewDataTemplate">
<Grid Margin="20,5" DragOver="Grid_DragOver"
BorderBrush="White" BorderThickness="5" AllowDrop="True">
<TextBlock Margin="10" LineHeight="40" FontSize="32" FontWeight="Bold"/>
</Grid>
</DataTemplate>
</Page.Resources>
This way Grid_DragOver will be invoked when mouse pointer enter inside the Grid in DataTemplate.
And if you use binding List<YourFolderClass> as data source, you'll get folder in DataContext. For example I used this:
var SampleData = new ObservableCollection<string>
{
"My Research Paper",
"Electricity Bill",
"My To-do list",
"TV sales receipt",
"Water Bill",
"Grocery List",
"Superbowl schedule",
"World Cup E-ticket"
};
You can see all code in gist.
I have implemented textblock in Listbox ItemTemplate/data template. It is databound to "Data" which is getting read from an xml file. Everything works fine but, the text is getting trimmed in textblocks and a there ia a blank space. I know the reason and it is due to limitations in textblock. Now i tried to use, Scrollable TextBlock for WP7 from Alex Yakhnin's Blog but I am not able to understand how to implement this in my project?
C# CODE:
string XMLTagNameBody = "page";
private void ParseHeaderBody()
{
XDocument SunderGutkaXMLInstance = XDocument.Load(xmlFileToOpen);
var XMLBody = from query in SunderGutkaXMLInstance.Descendants(XMLTagNameBody)
select new BodyContentClass
{
Data = (string)query.Element("data"),
};
ListBoxDisplayContent.ItemsSource = XMLBody;
}
public class BodyContentClass
{
string book;
string data;
public string Book
{
get { return book; }
set { book = value; }
}
public string Data
{
get { return data; }
set { data = value; }
}
}
XAML Code:
<ListBox Margin="0,25,0,32"
x:Name="ListBoxDisplayContent"
FontSize="48"
HorizontalAlignment="Center">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel x:Name="ListBoxDisplayContentStackPanel"
Margin="10"
HorizontalAlignment="Center">
<TextBlock x:Name="MainContentDisplayTextBlock"
TextWrapping="Wrap"
Text="{Binding Data}"
TextAlignment="Center"
HorizontalAlignment="Center" />
<Image x:Name="dividerImage"
Stretch="Fill"
Source="/Assets/MainContentDivider.png"
Opacity="1"></Image>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Links for Alex Yakhnin's Blog/Scrollable TextBlock for WP7:
http://social.msdn.microsoft.com/Forums/windowsapps/en-US/3af9bc99-2526-49fc-b4a5-4170e12d11ab/do-textblocks-have-a-max-line-limit-if-so-how-do-i-increase-it?forum=wpdevelop
http://blogs.msdn.com/b/priozersk/archive/2010/09/08/creating-scrollable-textblock-for-wp7.aspx
You can create a custom control and than it can be added to your project like:
<StackPanel x:Name="ListBoxDisplayContentStackPanel" Margin="10"
HorizontalAlignment="Center">
<my:ScrollableTextBlock Text="{Binding Data}"
HorizontalAlignment="Left" Name="scrollableTextBlock1"
VerticalAlignment="Top" Height="618" Width="427" Margin="12,-11,0,0" />
<TextBlock x:Name="MainContentDisplayTextBlock"
TextWrapping="Wrap"
TextAlignment="Center"
HorizontalAlignment="Center" />
<Image x:Name="dividerImage"
Stretch="Fill"
Source="/Assets/MainContentDivider.png"
Opacity="1"></Image>
</StackPanel>
Where my is the namespace of your control.
I have following xaml code:
<Window x:Class="WPF_les_3.Oefening_4"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Oefening_4" Height="300" Width="300">
<StackPanel Width="auto" Margin="20px">
<ComboBox Width="100" SelectionChanged="ComboBox_Selected" x:Name="comboBox">
<ComboBoxItem>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="Red" Height="20" Width="20"/>
<TextBlock Text=" Red"/>
</StackPanel>
</ComboBoxItem>
<ComboBoxItem>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="Yellow" Height="20" Width="20"/>
<TextBlock Text=" Yellow"/>
</StackPanel>
</ComboBoxItem>
<ComboBoxItem>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="Green" Height="20" Width="20"/>
<TextBlock Text=" Green"/>
</StackPanel>
</ComboBoxItem>
</ComboBox>
</StackPanel>
As you see, inside my ComboboxItems I have a rectangle and a textblock. Now I want to retreive the fill color of the rectangle (or the text of the textblock, it's the same) when my selectionchanged event is handled, so I can change the background of the window according to the selected color (which is the goal of the excercise).
To elaborate on my comment above, this is the Correct way to achieve what you need in WPF:
First of all, create a proper ViewModel that contains the list of available colors and a SelectedColor property:
public class ColorsViewModel
{
public ObservableCollection<string> Colors { get; private set; }
private string _selectedColor;
public string SelectedColor
{
get { return _selectedColor; }
set
{
_selectedColor = value;
MessageBox.Show("Selected Color: " + value); //message box here to show the code is actually working.
}
}
//... More code here in a moment
}
Then, make sure you populate the color collection with relevant data. In the case of colors specifically, WPF has built-in TypeConverters that can convert from (for example) string to System.Windows.Media.Color implicitly, therefore we can leverage that to simplify our code and use simple strings:
//Continuation of the above code
public ColorsViewModel()
{
Colors = new ObservableCollection<string>
{
"Red",
"Green",
"Blue",
"Yellow",
};
}
And finally create the UI in XAML using proper DataBinding:
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<ComboBox ItemsSource="{Binding Colors}"
SelectedItem="{Binding SelectedColor}"
VerticalAlignment="Center" HorizontalAlignment="Center">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="{Binding}" Height="20" Width="20"/>
<TextBlock Text="{Binding}"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</Window>
Result:
The change event is fired and the ComboBox.SelectedItem has the info you need.
You have to analyze the SelectedItem like my following method:
private void comboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ComboBoxItem comboBoxItem = this.comboBox.SelectedItem as ComboBoxItem;
if (comboBoxItem != null)
{
StackPanel stackPanel = comboBoxItem.Content as StackPanel;
if(stackPanel != null && stackPanel.Children[0] is Rectangle)
{
var fill = (stackPanel.Children[0] as Rectangle).Fill;
}
}
}
Here you get the fill of the rectangle and can handle this or do your stuff.
But be patient, this code is created exactly for you sample (ComboBoxItem with Content StackPanel with Children[0] as Rectangle). Changes will iterrupt the process ;)
Im trying to add items to the combo box from the code behind to the item template but im getting null. This is what I have so far:
XAML:
<ListBox x:Name="lsbCiertoYFalsoInsideTemplate" Margin="40,0,0,0" ItemTemplate="{StaticResource CiertoYFalsoExcerciseDataTemplate}"/>
App.xaml:
<DataTemplate x:Key="CiertoYFalsoExcerciseDataTemplate">
<Grid>
<StackPanel x:Name="stckCiertoYFalsoInsideTemplate" Margin="0" Orientation="Vertical" Width="1100">
<StackPanel x:Name="stckPreguntasCiertoYFalso" Orientation="Horizontal">
<Grid Height="50" Width="65" DataContext="{Binding CustomValueList}" VerticalAlignment="Top">
<ComboBox x:Name="cbExercises" Style="{StaticResource SA_ComboBoxStyle}" ItemsSource="{Binding CustomOption}" BorderBrush="#CC8C8C8C" VerticalAlignment="Top">
</ComboBox>
</Grid>
<TextBlock HorizontalAlignment="Center" Margin="5,3,0,0" TextWrapping="Wrap" Text="{Binding QuestionNumber}" VerticalAlignment="Top" FontWeight="Bold" Foreground="Black" Width="26" FontFamily="{Binding FontFamily, Source={StaticResource TextBlockStyleManager}}" FontSize="{Binding FontSize, Source={StaticResource TextBlockStyleManager}}"/>
<TextBlock TextWrapping="Wrap" Text="{Binding Question}" Foreground="Black" VerticalAlignment="Top" FontSize="{Binding FontSize, Source={StaticResource TextBlockStyleManager}}" Margin="10,3,0,0" Width="968" FontFamily="{Binding FontFamily, Source={StaticResource TextBlockStyleManager}}"/>
</StackPanel>
</StackPanel>
</Grid>
</DataTemplate>
The error im getting is object out of range.
Code:
private void ComboBoxExercises()
{
ComboBox comboBox = new ComboBox();
ComboboxItem item = new ComboboxItem();
item.Text = "A";
comboBox = (ComboBox)lsbCiertoYFalsoInsideTemplate.FindName("cbExercises");
comboBox.SelectedIndex = 0;
comboBox.Items.Add(item);
}
public class ComboboxItem
{
public string Text { get; set; }
public override string ToString()
{
return Text;
}
}
There's a disconnect in what you're trying to do here. You've specified an ItemTemplate - which defines how each item in the list will look.
But then you're trying to get one single ComboBox back out via the FindName function. Which leads me to believe that you're really intending to set the Template, not the ItemTemplate.
That said, I think the error you're getting is because you're setting the SelectedIndex to 0 when the ComboBox has no items in it. You're telling it to select the first one, but there's nothing to select. You should add the item first, then select it.