I'm getting the following Binding errors on my code and I don't know how to troubleshoot them. The bindings were generated by VS. I've tried adding presentation.tracesources (which is in the code below) but I get the same output as before.
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='ClimateSolutions.SuperTB', AncestorLevel='1''. BindingExpression:Path=myName; DataItem=null; target element is 'TextBlock' (Name=''); target property is 'Text' (type 'String')
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='ClimateSolutions.SuperTB', AncestorLevel='1''. BindingExpression:Path=isRequired; DataItem=null; target element is 'SuperTB' (Name='email'); target property is 'NoTarget' (type 'Object')
Here's my XAML:
<TextBox x:Class="ClimateSolutions.SuperTB"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d" Height="53" Width="296" FontSize="32"
xmlns:local="clr-namespace:ClimateSolutions"
xmlns:diagnostics="clr-namespace:System.Diagnostics;assembly=WindowsBase"
HorizontalAlignment="Left" Name="Blarg">
<TextBox.Style>
<Style TargetType="TextBox">
<Style.Triggers>
<Trigger Property="Text" Value="">
<Setter Property="Background">
<Setter.Value>
<VisualBrush Stretch="None">
<VisualBrush.Visual>
<TextBlock Foreground="Gray" FontSize="24" Text="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=local:SuperTB, AncestorLevel=1}, Path=myName, diagnostics:PresentationTraceSources.TraceLevel=High}">
</TextBlock>
</VisualBrush.Visual>
</VisualBrush>
</Setter.Value>
</Setter>
</Trigger>
<DataTrigger Binding="{Binding Path=isRequired, RelativeSource={RelativeSource FindAncestor, AncestorType=local:SuperTB, AncestorLevel=1}}" Value="False">
<Setter Property="Text" Value="100" />
</DataTrigger>
</Style.Triggers>
</Style>
</TextBox.Style>
and here's the CS for SuperTB:
namespace ClimateSolutions
{
/// <summary>
/// Interaction logic for SuperTB.xaml
/// </summary>
public partial class SuperTB : TextBox, INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(String Property)
{
var anEvent = this.PropertyChanged;
if (anEvent != null)
{
anEvent(this, new PropertyChangedEventArgs(Property));
}
}
private String MyName = "Unicorns!";
private static DependencyProperty myNameProperty = DependencyProperty.Register("myName", typeof(String), typeof(SuperTB));
public String myName
{
get { return MyName; }
set { MyName = value; NotifyPropertyChanged("myName"); }
}
DependencyProperty isRequiredProperty = DependencyProperty.Register("isRequired", typeof(Boolean), typeof(SuperTB));
public Boolean isRequired
{
get { return (Boolean)GetValue(isRequiredProperty); }
set { SetValue(isRequiredProperty, value); }
}
public SuperTB()
{
InitializeComponent();
myName = "Unicorns!";
}
}
}
EDIT : I have updated the code according to your comment. To summarize, since this is a custom control, you are less dependant on the MVVM pattern to build your component logic (and thus use code behind in you component) as soon as your componennt itself meets this needs (to be sort, make its properties to be as much bindable as you can). For example, in the updated code, you can now bind the default property, but you can also imagine exposing properties to set the foreground colors used to diaplay control name when there is no value, and so forth.
I tried several things with you original code (included solution provided by J cooper) and nothing seemed to work. It seems that there is a lot of issues with your code.
I managed to approach a solution by making your textbox a custom control.
Here is the Generic.xaml (the visual definition of your control) :
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Question_6514447">
<Style TargetType="{x:Type local:SuperTB2}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:SuperTB2}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<TextBox x:Name="PART_Input">
<TextBox.Style>
<Style TargetType="TextBox">
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=IsRequired}" Value="False">
<Setter Property="Text" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=DefaultTextValue}" />
</DataTrigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>
And here is the code behind of the control :
[TemplatePart(Name = "PART_Input")]
public class SuperTB2 : Control
{
private TextBox PART_Input;
static SuperTB2()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(SuperTB2), new FrameworkPropertyMetadata(typeof(SuperTB2)));
}
public SuperTB2()
{
Loaded += SuperTb2Loaded;
}
public override void OnApplyTemplate()
{
PART_Input = GetTemplateChild("PART_Input") as TextBox;
if (PART_Input != null)
{
PART_Input.GotFocus += PartInputGotFocus;
PART_Input.LostFocus += PartInputLostFocus;
}
}
void PartInputLostFocus(object sender, RoutedEventArgs e)
{
if (PART_Input.Text == string.Empty)
{
PART_Input.Text = Name;
PART_Input.Foreground = new SolidColorBrush(Colors.Gray);
}
}
void PartInputGotFocus(object sender, RoutedEventArgs e)
{
if (PART_Input.Text.Equals(Name))
{
PART_Input.Text = string.Empty;
PART_Input.Foreground = new SolidColorBrush(Colors.Black);
}
}
void SuperTb2Loaded(object sender, RoutedEventArgs e)
{
if (PART_Input.Text == string.Empty)
{
PART_Input.Text = Name;
PART_Input.Foreground = new SolidColorBrush(Colors.Gray);
}
}
private static DependencyProperty myNameProperty =
DependencyProperty.Register("MyName", typeof(string), typeof(SuperTB2), new PropertyMetadata("Unicorns !", NameChanged));
private static void NameChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
}
public string MyName
{
get { return (string)GetValue(myNameProperty); }
set { SetValue(myNameProperty, value); }
}
DependencyProperty isRequiredProperty =
DependencyProperty.Register("IsRequired", typeof(bool), typeof(SuperTB2), new PropertyMetadata(false, IsReqChanged));
private static void IsReqChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
}
public bool IsRequired
{
get { return (bool)GetValue(isRequiredProperty); }
set { SetValue(isRequiredProperty, value); }
}
public string DefaultTextValue
{
get { return (string)GetValue(DefaultTextValueProperty); }
set { SetValue(DefaultTextValueProperty, value); }
}
// Using a DependencyProperty as the backing store for DefaultTextValue. This enables animation, styling, binding, etc...
public static readonly DependencyProperty DefaultTextValueProperty =
DependencyProperty.Register("DefaultTextValue", typeof(string), typeof(SuperTB2), new UIPropertyMetadata("100"));
}
And an example of use of the component :
<Grid>
<StackPanel>
<Question_6514447:SuperTB2 x:Name="FirstName" IsRequired="true" DefaultTextValue="200"/>
</StackPanel>
</Grid>
With this updated code, I think you can acheive almost all the behaviors your needed !
Hope this will help !
Do not use relative source in your binding expressions. Relative source is used to access elements higher in the element tree. It seems as though you were using it in terms of object inheritance.
<Trigger Property="Text" Value="">
<Setter Property="Background">
<Setter.Value>
<VisualBrush Stretch="None">
<VisualBrush.Visual>
<TextBlock Foreground="Gray" FontSize="24" Text="{Binding Path=myName, diagnostics:PresentationTraceSources.TraceLevel=High}">
</TextBlock>
</VisualBrush.Visual>
</VisualBrush>
</Setter.Value>
</Setter>
</Trigger>
<DataTrigger Binding="{Binding Path=isRequired}" Value="False">
<Setter Property="Text" Value="100" />
</DataTrigger>
Related
I have some problem in changing Ellipse Fill value based on data binding a boolean.
true = Lime colour
false = Red colour
My code does not prompt out any error but also does not show fill value colours.
WPF XAML code:
<Ellipse x:Name="damageSpoolSlot1" HorizontalAlignment="Left" Height="45" Stroke="Black" VerticalAlignment="Top" Width="70" Grid.Column="1" Margin="203.4,377.2,0,0" Grid.Row="2">
<Ellipse.Style>
<Style TargetType="{x:Type Ellipse}">
<Style.Triggers>
<DataTrigger Binding="{Binding DamageSpoolSlot1PresenceSensorOn}" Value="false">
<Setter Property="Fill" Value="Red"/>
</DataTrigger>
<DataTrigger Binding="{Binding DamageSpoolSlot1PresenceSensorOn}" Value="true">
<Setter Property="Fill" Value="Lime"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Ellipse.Style>
</Ellipse>
Code-Behind:
Binding myBinding = new Binding("DamageSpoolSlot1PresenceSensorOn")
{
Source = MyBinding.Instance
};
BindingOperations.SetBinding(damageSpoolSlot1, Ellipse.FillProperty, myBinding);
My data binding code:
public class MyBinding : INotifyPropertyChanged
{
private static volatile MyBinding instance;
private static object syncRoot = new Object();
public static MyBinding Instance
{
get
{
if (instance == null)
{
lock (syncRoot)
{
if (instance == null)
instance = new MyBinding();
}
}
return instance;
}
}
public event PropertyChangedEventHandler PropertyChanged;
private bool _DamageSpoolSlot1PresenceSensorOn = false;
public bool DamageSpoolSlot1PresenceSensorOn
{
get { return _DamageSpoolSlot1PresenceSensorOn; }
set
{
if (value != _DamageSpoolSlot1PresenceSensorOn)
{
_DamageSpoolSlot1PresenceSensorOn = value;
OnPropertyChanged("DamageSpoolSlot1PresenceSensorOn");
}
}
}
}
The data triggers in your style bind to the DataContext of the Ellipse. This means they expect an object that has a property DamageSpoolSlot1PresenceSensorOn. However, your binding fails in two ways.
The binding already binds to the DamageSpoolSlot1PresenceSensorOn of the MyBinding.Instance, so the data triggers will try to bind to another sub property DamageSpoolSlot1PresenceSensorOn that simply does not exist, the DataContext already is this property.
The binding binds the Fill property, which expects a Brush, but the data triggers bind to the DataContext of the Ellipse, not the Fill property.
Change the binding like this, so it will deliver the Instace to the DataContext property.
Binding myBinding = new Binding()
{
Source = MyBinding.Instance
};
BindingOperations.SetBinding(damageSpoolSlot1, Ellipse.DataContextProperty, myBinding);
Another simpler option is to create the binding to the MyBinding.Instance directly in XAML. Bind the DataContext property using a binding that specifies the static MyBinding.Instance as Source with the x:Static markup extension.
<Ellipse x:Name="damageSpoolSlot1" HorizontalAlignment="Left" Height="45" Stroke="Black" VerticalAlignment="Top" Width="70" Margin="203.4,377.2,0,0"
DataContext="{Binding Source={x:Static local:MyBinding.Instance}}">
<Ellipse.Style>
<Style TargetType="{x:Type Ellipse}">
<Setter Property="Fill" Value="Red"/>
<Style.Triggers>
<DataTrigger Binding="{Binding DamageSpoolSlot1PresenceSensorOn}" Value="True">
<Setter Property="Fill" Value="Lime"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Ellipse.Style>
</Ellipse>
As #Clemens pointed out, you could also simply set the DataContext in code-behind.
damageSpoolSlot1.DataContext = MyBinding.Instance;
I have dynamic Datagrid where columns creating programmatically and assigning items. After update I'm getting binding errors and I don't know how avoid them,
It seems that the styles are binded to Items in Visual tree and when updating items the triggers running on orphan data
<local:PerBalanceReportDataGrid Background="Transparent" RowBackground="Transparent" Panel.ZIndex="1000"
FrozenColumnCount="1"
ScrollViewer.CanContentScroll="True"
HorizontalScrollBarVisibility="Visible"
ScrollViewer.ScrollChanged="PerBalanceReportDataGrid_ScrollChanged"
Grid.Row="1"
ColumnWidth="150"
x:Name="PerBalanceReportDataGrid" >
<local:PerBalanceReportDataGrid.CellStyle>
<Style TargetType="DataGridCell">
<Setter Property="Foreground" Value="{Binding RelativeSource={RelativeSource Mode=Self}, Converter={StaticResource textToColorConverter}}"/>
<Setter Property="FontWeight" Value="{Binding RelativeSource={RelativeSource Mode=Self}, Converter={StaticResource textToBoldConverter}}"/>
</Style>
</local:PerBalanceReportDataGrid.CellStyle>
<local:PerBalanceReportDataGrid.RowStyle>
<Style TargetType="DataGridRow">
<Setter Property="Background" Value="Transparent"/>
</Style>
</local:PerBalanceReportDataGrid.RowStyle>
<local:PerBalanceReportDataGrid.ColumnHeaderStyle>
<Style TargetType="DataGridColumnHeader">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="SeparatorVisibility" Value="Hidden" />
</Style>
</local:PerBalanceReportDataGrid.ColumnHeaderStyle>
</local:PerBalanceReportDataGrid>
public class ExtendedDataGrid<TDynamicRowType, TCellDataType> : DataGrid where TDynamicRowType : DynamicDataRow<TCellDataType>
{
public static readonly DependencyProperty DataTableProperty =
DependencyProperty.Register(
"DataTable",
typeof(DataTable<TDynamicRowType, TCellDataType>),
typeof(ExtendedDataGrid<TDynamicRowType, TCellDataType>),
new PropertyMetadata(null, OnDataTablePropertyChanged));
public DataTable<TDynamicRowType, TCellDataType> DataTable
{
get { return (DataTable<TDynamicRowType, TCellDataType>)GetValue(DataTableProperty); }
set { SetValue(DataTableProperty, value); }
}
private static void OnDataTablePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
if (d is ExtendedDataGrid<TDynamicRowType, TCellDataType> grid)
grid.Init();
}
private void Init()
{
if (DataTable == null)
return;
ItemsSource = null;
Columns.Clear();
SetValue(DataGridReadOnlyBehavior<TDynamicRowType>.PredicateProperty, DataTable.IsReadOnlyPredicate);
Columns.AddRange(DataTable.Columns.Select(FromInfo));
ItemsSource = DataTable.Rows;
ICollectionView view = CollectionViewSource.GetDefaultView(ItemsSource);
view.GroupDescriptions.AddRange(
DataTable.GroupByProperties.Select(x => new PropertyGroupDescription(x)));
ExtendedColumn<TCellDataType> FromInfo(ColumnInfo info) => new (info);
}
}
public class PerBalanceReportDataGrid : ExtendedDataGrid<PerBalanceReportDataRow, string>
{
static PerBalanceReportDataGrid() =>
DefaultStyleKeyProperty.OverrideMetadata(
typeof(PerBalanceReportDataGrid),
new FrameworkPropertyMetadata(typeof(PerBalanceReportDataGrid)));
}
After I'm updating the table I'm getting the following errors
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.DataGridRow', AncestorLevel='1''. BindingExpression:Path=Foreground; DataItem=null; target element is 'DataGridCell' (Name=''); target property is 'Foreground' (type 'Brush')
In a WPF Project I have some restyled DataGridColumnHeaders of a DataGrid which show a ComboBox for each DataGridColumnHeader. When the user selects from the ComboBox's the SelectionChanged handler (in the code behind) updates an Array of ColumnOptionViewModel objects on the MainWindowViewModel with the newest selection.
At this point some code also works out if there are any duplicate selections in this array, and then sets an IsDuplicate Boolean property on the ColumnOptionViewModel that are duplicates. The idea is that a DataTrigger picks up the change in IsDuplicate and changes the Background of a TextBlock in the DataTemplate of the ItemTemplate for the duplicate ComboBox's to Red.
However, this trigger is not firing. The IsDuplicate properties are being set ok, and everything else works as expected. What am I doing wrong?
Here is the XAML for the Window:
<Window x:Class="TestDataGrid.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:TestDataGrid"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<DataGrid Grid.Row="1" x:Name="dataGrid" ItemsSource="{Binding Records}">
<DataGrid.ColumnHeaderStyle>
<Style TargetType="DataGridColumnHeader">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<StackPanel>
<ComboBox x:Name="cbo"
ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}},Path=DataContext.ColumnOptions}"
SelectionChanged="cbo_SelectionChanged">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock x:Name="txt" Text="{Binding Name}"/>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding ElementName=cbo, Path=SelectedItem.IsDuplicate}">
<Setter TargetName="txt" Property="Background" Value="Red"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DataGrid.ColumnHeaderStyle>
</DataGrid>
</Grid>
CODE BEHIND:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.DataContext = new MainWindowViewModel(RecordProvider.GetRecords());
}
private void cbo_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
var vm = (MainWindowViewModel)DataContext;
var selectionChangedCombo = (ComboBox)e.Source;
var dataGridColumnHeader = selectionChangedCombo.TemplatedParent as DataGridColumnHeader;
vm.ColumnSelections[dataGridColumnHeader.DisplayIndex] = selectionChangedCombo.SelectedItem as ColumnOptionViewModel;
CheckForDuplicates();
}
private void CheckForDuplicates()
{
var vm = (MainWindowViewModel)DataContext;
var duplicates = vm.ColumnSelections.GroupBy(x => x.Name)
.Where(g => g.Skip(1).Any())
.SelectMany(g => g);
foreach (var option in duplicates)
{
option.IsDuplicate = true;
}
}
}
MainWindowViewModel :
public class MainWindowViewModel : ViewModelBase
{
public ObservableCollection<ColumnOptionViewModel> _columnOptions = new ObservableCollection<ColumnOptionViewModel>();
public ObservableCollection<RecordViewModel> _records = new ObservableCollection<RecordViewModel>();
ColumnOptionViewModel[] _columnSelections = new ColumnOptionViewModel[3];
public MainWindowViewModel(IEnumerable<Record> records)
{
foreach (var rec in records)
{
Records.Add(new RecordViewModel(rec));
}
ColumnOptions.Add(new ColumnOptionViewModel(TestDataGrid.ColumnOptions.ColumnOption1));
ColumnOptions.Add(new ColumnOptionViewModel(TestDataGrid.ColumnOptions.ColumnOption2));
ColumnOptions.Add(new ColumnOptionViewModel(TestDataGrid.ColumnOptions.ColumnOption3));
ColumnSelections[0] = ColumnOptions[0];
ColumnSelections[1] = ColumnOptions[1];
ColumnSelections[2] = ColumnOptions[2];
}
public ObservableCollection<ColumnOptionViewModel> ColumnOptions
{
get { return _columnOptions; }
set { _columnOptions = value; }
}
public ColumnOptionViewModel[] ColumnSelections
{
get { return _columnSelections; }
set { _columnSelections = value; }
}
public ObservableCollection<RecordViewModel> Records
{
get { return _records; }
set { _records = value; }
}
}
ColumnOptionViewModel :
public class ColumnOptionViewModel : ViewModelBase
{
ColumnOptions _colOption;
public ColumnOptionViewModel(ColumnOptions colOption )
{
_colOption = colOption;
}
public string Name
{
get { return _colOption.ToString(); }
}
public override string ToString()
{
return Name;
}
private bool _isDuplicate = false;
public bool IsDuplicate
{
get { return _isDuplicate; }
set
{ _isDuplicate = value;
OnPropertyChanged();
}
}
}
EDIT:
ViewModelBase :
public abstract class ViewModelBase : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
If you are trying to bind to the IsDuplicate property of the SelectedItem in the ComboBox you could use a RelativeSource.
You should also set the Value property of the DataTrigger to true/false depending on when you want the Background property of the TextBlock to be set to Red:
<ComboBox x:Name="cbo" ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}},Path=DataContext.ColumnOptions}"
SelectionChanged="cbo_SelectionChanged">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock x:Name="txt" Text="{Binding Name}"/>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding Path=SelectedItem.IsDuplicate, RelativeSource={RelativeSource AncestorType=ComboBox}}" Value="True">
<Setter TargetName="txt" Property="Background" Value="Red"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
As #mm8 said, the Value is not chosen in your DataTrigger.
If that doesn't work, you can try using Trigger directly on TextBlock instead of DataTemplate.Triggers:
<TextBlock>
<TextBlock.Style>
<Style TargetType="TextBlock">
<Setter Property="Background" Value="White"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=IsDuplicate}" Value="True">
<Setter Property="Background" Value="Red"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
Also, background and foreground values in controls that have selectable items can be tricky. For example, you may want to disable default selection colors (unfortunately then you will have to manage selected/focused background yourself):
<ComboBox.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="Transparent" />
</ComboBox.Resources>
I have a Xaml page with style property for a text box. Whenever a user clicks the button with the textbox empty I need to display the validation error. Right now even when the textbox is empty and the button is pressed, a messagebox with empty text pops up. Even the Applicatin Exception is not working.. Please help...
Xaml:
<Window.Resources>
<Style TargetType="{x:Type TextBox}">
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<DockPanel LastChildFill="True">
<TextBlock DockPanel.Dock="Right"
Foreground="Orange"
FontSize="12pt">
!!!!
</TextBlock>
<Border BorderBrush="Green" BorderThickness="1">
<AdornedElementPlaceholder />
</Border>
</DockPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<Setter Property="ToolTip"
Value="{Binding RelativeSource={RelativeSource Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
My ViewModel Class:
public class Customer
{
private string _Text;
public string text
{
get
{
return _Text;
}
set
{
_Text = value;
if (string.IsNullOrEmpty(value))
{
throw new ApplicationException("Name is Mandatory");
}
}
}
public Customer()
{
}
private RelayCommand<object> _commandOkInstance;
public ICommand CommandOk
{
get
{
if (_commandOkInstance == null)
_commandOkInstance = new RelayCommand<object>(OkCommand);
return _commandOkInstance;
}
}
public void OkCommand(object obj)
{
MessageBox.Show(_Text);
}
}
Main Window.cs:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Customer c = new Customer();
this.DataContext = c;
}
}
I am creating an animation control and where I am trying to use data triggers. The issue is the dp property which I created is not getting changed/called when the trigger is fired. Here is the summary of behaviour I noticed.
1) The code behind of never gets called.
2) Property appears in XAML intellisense but the changes given in XAML never gets applied (design/runtime). But if I replace 'IsSpinning' in "public static readonly DependencyProperty IsSpinningProperty = DependencyProperty.Register("IsSpinning", typeof(bool), typeof(ProgressWaitSpinner), new UIPropertyMetadata(false));" to something else( say 'xyz') it starts working for property assignment, but throws runtime exception if styles are enabled.
3) When running the sample, The rectangle should be hidden instead of showing as Chocolate color, which is not happening.
4) Setter for changing color is working, which is from the user control, however the setter property on newly created property is not working.
I created a simplified sample here which shows the problem. Anyone got a clue what is going on please?
UserControl XAML:
<UserControl x:Class="CustomControls.ProgressWaitSpinner"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:CustomControls"
Height="191" Width="191">
<Grid x:Name="LayoutRoot">
<Label Height="32" Name="label1" VerticalAlignment="Top" />
</Grid>
</UserControl>
UserControl Code:
using System.Windows;
using System.Windows.Controls;
namespace CustomControls
{
public partial class ProgressWaitSpinner : UserControl
{
public ProgressWaitSpinner(){InitializeComponent();}
public bool IsSpinning
{
get
{
return (bool)GetValue(IsSpinningProperty);
}
set
{
if (value == true)
{
this.Visibility = System.Windows.Visibility.Visible;
}
else
{
this.Visibility = System.Windows.Visibility.Hidden;
}
SetValue(IsSpinningProperty, value);
}
}
public static readonly DependencyProperty IsSpinningProperty = DependencyProperty.Register("IsSpinning", typeof(bool), typeof(ProgressWaitSpinner), new UIPropertyMetadata(false));
}
}
MainWindow XAML:
<Window x:Class="WPFSpinnerWait.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:usrctrl="clr-namespace:CustomControls"
Title="MainWindow" Height="208" Width="228">
<Grid>
<usrctrl:ProgressWaitSpinner Height="40" x:Name="WaitSpinner" Margin="110,103,0,0" HorizontalAlignment="Left" Width="84" VerticalAlignment="Top">
<usrctrl:ProgressWaitSpinner.Style>
<Style>
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=label1, Path=Content}" Value="NotStarted"></Condition>
</MultiDataTrigger.Conditions>
<Setter Property="usrctrl:ProgressWaitSpinner.Background" Value="Red" />
<Setter Property="usrctrl:ProgressWaitSpinner.IsSpinning" Value="false"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=label1, Path=Content}" Value="Running"></Condition>
</MultiDataTrigger.Conditions>
<Setter Property="usrctrl:ProgressWaitSpinner.Background" Value="Chocolate" />
<Setter Property="usrctrl:ProgressWaitSpinner.IsSpinning" Value="true" />
</MultiDataTrigger>
</Style.Triggers>
</Style>
</usrctrl:ProgressWaitSpinner.Style>
</usrctrl:ProgressWaitSpinner>
<Button Content="NotStarted" Height="28" HorizontalAlignment="Left" Margin="38,22,0,0" Name="checkBox1" VerticalAlignment="Top" Width="136" Click="checkBox1_Checked" />
<Button Content="Running" Height="30" HorizontalAlignment="Left" Margin="38,56,0,0" Name="checkBox2" VerticalAlignment="Top" Width="136" Click="checkBox1_Checked" />
<Label Content="NotStarted" DataContext="usrctrl:ProgressWaitSpinner" Height="25" HorizontalAlignment="Left" Margin="38,92,0,0" Name="label1" VerticalAlignment="Top" Width="114" />
</Grid>
</Window>
MainWindow Code:
using System.Windows;
using System.Windows.Controls;
namespace WPFSpinnerWait
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void checkBox1_Checked(object sender, RoutedEventArgs e)
{
label1.Content = ((Button)sender).Content.ToString();
}
}
}
The code behind won't get called, DependancyProperties do not use the backing property when the property is change/used in Xaml, thay are only there for use in code behind as a helper, thay have no use in Xaml bindings
You can use the PropertyChanged event of the DependancyProperty instead
public bool IsSpinning
{
get { return (bool)GetValue(IsSpinningProperty); }
set { SetValue(IsSpinningProperty, value); }
}
// Using a DependencyProperty as the backing store for IsSpinning. This enables animation, styling, binding, etc...
public static readonly DependencyProperty IsSpinningProperty =
DependencyProperty.Register("IsSpinning", typeof(bool), typeof(ProgressWaitSpinner), new PropertyMetadata(false, OnIsSpinningChanged));
private static void OnIsSpinningChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
if (((bool)e.NewValue) == true)
{
(d as ProgressWaitSpinner).Visibility = System.Windows.Visibility.Visible;
}
else
{
(d as ProgressWaitSpinner).Visibility = System.Windows.Visibility.Hidden;
}
}
Edit:
For your second question, Try adding the TargetType for your Style so you can access the properties directly
<Style TargetType="{x:Type usrctrl:ProgressWaitSpinner}">
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=label1, Path=Content}" Value="NotStarted"></Condition>
</MultiDataTrigger.Conditions>
<Setter Property="Background" Value="Red" />
<Setter Property="IsSpinning" Value="false"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=label1, Path=Content}" Value="Running"></Condition>
</MultiDataTrigger.Conditions>
<Setter Property="Background" Value="Chocolate" />
<Setter Property="IsSpinning" Value="true" />
</MultiDataTrigger>
</Style.Triggers>
</Style>