Binding properties from CustomControl to page in WPF - c#

I want to bind properties from CustomControl to my page, then back to CustomControl and calculate quantity of pages and display it in list.
My code look like.
CustomControl
public partial class CustomControl : UserControl
public CustomControl()
{
InitializeComponent()
}
public int PageSelected
{
get
{
return (int)GetValue(PageSelectedProperty);
}
set
{
SetValue(PageSelectedProperty, value);
}
}
public static readonly DependencyProperty PageSelectedProperty = DependencyProperty.Register("PageSelected", typeof(int), typeof(CustomControl), new PropertyMetadata(null));
public int RecordsPerPage
{
get
{
return (int)GetValue(RecordsPerPageProperty);
}
set
{
SetValue(RecordsPerPageProperty, value);
}
}
public static readonly DependencyProperty RecordsPerPageProperty = DependencyProperty.Register("RecordsPerPage", typeof(int), typeof(CustomControl), new PropertyMetadata(null));
public IList<int> RecordsPerPageList
{
get
{
return (IList<int>)GetValue(RecordsPerPageListProperty);
}
set
{
SetValue(RecordsPerPageListProperty, value);
}
}
public static readonly DependencyProperty RecordsPerPageListProperty = DependencyProperty.Register("RecordsPerPageList", typeof(List<int>), typeof(CustomControl), new PropertyMetadata(null));
public int RecordsCount
{
get
{
return (int)GetValue(RecordsCountProperty);
}
set
{
SetValue(RecordsCountProperty, value);
CreatePagesList();
}
}
public static readonly DependencyProperty RecordsCountProperty = DependencyProperty.Register("RecordsCount", typeof(int), typeof(CustomControl), new PropertyMetadata(null));
public IList<int> PagesList
{
get
{
return (IList<int>)GetValue(PagesListProperty);
}
set
{
SetValue(PagesListProperty, value);
}
}
public static readonly DependencyProperty PagesListProperty = DependencyProperty.Register("PagesList", typeof(List<int>), typeof(CustomControl), new PropertyMetadata(null));
public int PagesCount
{
get
{
return (int)GetValue(PagesCountProperty);
}
set
{
SetValue(PagesCountProperty, value);
}
}
public static readonly DependencyProperty PagesCountProperty = DependencyProperty.Register("PagesCount", typeof(int), typeof(CustomControl), new PropertyMetadata(null));
Custom Control xaml
<UserControl x:Class="Mtrx.CustomControls.CustomControl"
mc:Ignorable="d"
d:DesignHeight="90" Width="200">
<Grid >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="100"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="90" />
</Grid.RowDefinitions>
<ComboBox Width="40" Height="20" Grid.Column="1" Margin="0,5,0,5"
ItemsSource="{Binding RelativeSource={RelativeSource AncestorType=UserControl}, Path=PagesList}"
SelectedItem="{Binding RelativeSource={RelativeSource AncestorType=UserControl}, Path=PageSelected, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
HorizontalContentAlignment="Center"/>
<ComboBox Width="40" Height="20" Grid.Column="9" Margin="0,5,0,5"
ItemsSource="{Binding RelativeSource={RelativeSource AncestorType=UserControl}, Path=RecordsPerPageList, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
SelectedItem="{Binding RelativeSource={RelativeSource AncestorType=UserControl}, Path=RecordsPerPage, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
HorizontalContentAlignment="Center"/>
</Grid>
</UserControl>
Page xaml.cs
public class PageVievModel:AbstractPage
public int RowsCount
{
get
{
return _rowsCount;
}
set
{
if (value != _rowsCount)
{
_rowsCount = value;
RaisePropertyChanged("RowsCount");
}
}
}
private int _rowsCount; //we get it from other place
public int DGRecordsMax
{
get
{
return _dgRecordsMax;
}
set
{
if (value != _dgRecordsMax)
{
_dgRecordsMax = value;
if (value > 0)
{
DataGridRecordsMaxCount = value.ToString();
Settings.Default.Save();
}
RaisePropertyChanged("DGRecordsMax");
}
}
}
private int _dgRecordsMax;
public IList<int> DGRecordsMaxList
{
get
{
return _dGRecordsMaxList;
}
set
{
if (_dGRecordsMaxList != value)
{
_dGRecordsMaxList = value;
RaisePropertyChanged("DGRecordsMaxList");
}
}
}
private IList<int> _dGRecordsMaxList = new List<int>();
public IList<int> PagesList
{
get
{
return _pagesList;
}
set
{
if (_pagesList != value)
{
_pagesList = value;
RaisePropertyChanged("PagesList");
}
}
}
private IList<int> _pagesList = new List<int>();
public int PagesCount
{
get
{
return _pagesCount;
}
set
{
if (value != _pagesCount)
{
_pagesCount = value;
RaisePropertyChanged("PagesCount");
}
}
}
private int _pagesCount;
public IList<int> CurrentPageList
{
get
{
return _currentPageList;
}
set
{
if (_currentPageList != value)
{
_currentPageList = value;
RaisePropertyChanged("CurrentPageList");
}
}
}
private IList<int> _currentPageList;
Page xaml
<UserControl x:Class="SomeClass"
mc:Ignorable="d"
d:DesignHeight="400" d:DesignWidth="800"
IsEnabled="{Binding AllowInput, Converter={StaticResource AnyToBooleanConverter}}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<DockPanel>
<SomeClass:CustomControl Width="280" Height="190"
RecordsCount="{Binding RowsCount, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
RecordsPerPage="{Binding DGRecordsMax, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay }"
RecordsPerPageList="{Binding DGRecordsMaxList, Mode=TwoWay}"
PagesCount="{Binding PagesCount, Mode=TwoWay}"
PageSelected="{Binding CurrentPage, Mode=TwoWay}"
PagesList="{Binding PagesList, Mode=TwoWay}"
RecordsFrom="{Binding RecordsFrom, Mode=TwoWay}"
RecordsTo="{Binding RecordsTo, Mode=TwoWay}"
DockPanel.Dock="Right"
VerticalAlignment="Bottom"/>
</WrapPanel.Resources>
</WrapPanel>
</Grid>
</UserControl>
When I am trying to run my program there are empty lists, earlier when I just kept more properties in Page it was working fine.
I would be greatful for help. It's hard to understand for me how make this two way bindable properties.

I tried to make an example using your code.
For me it worked if I changed both IList and List to ObservableCollection, e.g.
using System.Collections.ObjectModel;
....
public ObservableCollection<int> PagesList
{
get
{
return (ObservableCollection<int>)GetValue ( PagesListProperty );
}
set
{
SetValue ( PagesListProperty, value );
}
}
public static readonly DependencyProperty PagesListProperty = DependencyProperty.Register("PagesList", typeof(ObservableCollection<int>), typeof(CustomControl), new PropertyMetadata(null));
Note that I changed both the Property definition and the DependencyProperty definition.
Your code is a bit messy, for example you have a DockPanel tag which is closed with /WrapPanel, which obviously will not compile.
<DockPanel>
</WrapPanel>

Related

How to set custom properties in an inherited control in xaml

I built a custom control TabularListView based on ListView with a new Property, an ObservableCollection of TabularListViewHeaderColumn.
TabularListView:
class TabularListView : ListView
{
public TabularListView()
{
Columns = new ObservableCollection<TabularListViewHeaderColumn>();
}
public ObservableCollection<TabularListViewHeaderColumn> Columns
{
get { return (ObservableCollection<TabularListViewHeaderColumn>)GetValue(ColumnsProperty); }
set { SetValue(ColumnsProperty, value); }
}
public static readonly DependencyProperty ColumnsProperty =
DependencyProperty.Register("Columns", typeof(ObservableCollection<TabularListViewHeaderColumn>), typeof(TabularListView), new PropertyMetadata(new ObservableCollection<TabularListViewHeaderColumn>()));
}
TabularListViewHeaderColumn:
class TabularListViewHeaderColumn : ContentControl
{
public string Title
{
get { return (string)GetValue(TitleProperty); }
set { SetValue(TitleProperty, value); }
}
public static readonly DependencyProperty TitleProperty =
DependencyProperty.Register("Title", typeof(string), typeof(TabularListViewHeaderColumn), new PropertyMetadata(string.Empty));
public string MappingName
{
get { return (string)GetValue(MappingNameProperty); }
set { SetValue(MappingNameProperty, value); }
}
public static readonly DependencyProperty MappingNameProperty =
DependencyProperty.Register("MappingName", typeof(string), typeof(TabularListViewHeaderColumn), new PropertyMetadata(string.Empty));
}
I try to use it like shown below, setting the TabularListViewHeaderColumns directly in XAML:
<Controls:TabularListView>
<Controls:TabularListView.Header>
<ItemsControl>
<DataTemplate>
<Button Content="{Binding Title}" Width="{Binding Width}"
FontWeight="Bold"/>
</DataTemplate>
</ItemsControl>
</Controls:TabularListView.Header>
<Controls:TabularListView.Columns>
<Controls:TabularListViewHeaderColumn Title="Test" MappingName="Inactive" Width="60"/>
<Controls:TabularListViewHeaderColumn Title="Articlenumber" MappingName="DeviceType.ArticleNo" Width="170"/>
<Controls:TabularListViewHeaderColumn Title="Serialnumber" MappingName="SerialNo" Width="170"/>
<Controls:TabularListViewHeaderColumn Title="Inventorynumber" MappingName="EndCustNo" Width="170"/>
<Controls:TabularListViewHeaderColumn Title="Description" MappingName="DeviceType.Description1" Width="300"/>
</Controls:TabularListView.Columns>
</Controls:TabularListView>
Usualy when creating a regular Custom Control like in this example https://social.technet.microsoft.com/wiki/contents/articles/32828.uwp-how-to-create-and-use-custom-control.aspx , I need to bind the respected property to the DependencyProperty, but since I only inherit from ListView and don't have any Xaml, I'm quiet confused how to do so.

Labeled ComboBox in Windows 10 Universal App

similar to my Labeled TextBox, which issues are resolved in:
Labeled TextBox in Windows Universal App
I got two issues in my Labeled Combobox, but first the Code:
Generic.xaml:
<Style TargetType="template:LabeledComboBox">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="template:LabeledComboBox">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<TextBlock Text="{TemplateBinding Label}" FontWeight="Bold" VerticalAlignment="Center" Margin="10,0" />
<ComboBox x:Name="PART_ComboBox" ItemsSource="{TemplateBinding ItemsSource}" SelectedIndex="{TemplateBinding SelectedIndex}" SelectedValue="{TemplateBinding SelectedValue}" SelectedValuePath="{TemplateBinding SelectedValuePath}" DisplayMemberPath="{TemplateBinding DisplayMemberPath}" VerticalAlignment="Center" Margin="20,0,10,0" Grid.Row="1" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
LabeledComboBox.cs:
[TemplatePart(Name = "PART_ComboBox", Type = typeof(ComboBox))]
public sealed class LabeledComboBox : Control, IParameterReturnable
{
public static readonly DependencyProperty LabelProperty = DependencyProperty.Register("Label", typeof(string), typeof(LabeledComboBox), new PropertyMetadata(""));
public string Label
{
get { return GetValue(LabelProperty).ToString(); }
set { SetValue(LabelProperty, value); }
}
public static readonly DependencyProperty ItemsSourceProperty = DependencyProperty.Register("ItemsSource", typeof(object), typeof(LabeledComboBox), new PropertyMetadata(null));
public object ItemsSource
{
get { return GetValue(ItemsSourceProperty); }
set { SetValue(ItemsSourceProperty, value); }
}
public static readonly DependencyProperty SelectedIndexProperty = DependencyProperty.Register("SelectedIndex", typeof(int), typeof(LabeledComboBox), new PropertyMetadata(default(int)));
public int SelectedIndex
{
get { return (int) GetValue(SelectedIndexProperty); }
set { SetValue(SelectedIndexProperty, value); }
}
public static readonly DependencyProperty SelectedValueProperty = DependencyProperty.Register("SelectedValue", typeof(object), typeof(LabeledComboBox), new PropertyMetadata(null));
public object SelectedValue
{
get { return GetValue(SelectedValueProperty); }
set { SetValue(SelectedValueProperty, value); }
}
public static readonly DependencyProperty SelectedValuePathProperty = DependencyProperty.Register("SelectedValuePath", typeof(string), typeof(LabeledComboBox), new PropertyMetadata(default(string)));
public string SelectedValuePath
{
get { return GetValue(SelectedValuePathProperty).ToString(); }
set { SetValue(SelectedValuePathProperty, value); }
}
public static readonly DependencyProperty DisplayMemberPathProperty = DependencyProperty.Register("DisplayMemberPath", typeof(string), typeof(LabeledComboBox), new PropertyMetadata(default(string)));
public string DisplayMemberPath
{
get { return GetValue(DisplayMemberPathProperty).ToString(); }
set { SetValue(DisplayMemberPathProperty, value); }
}
private ComboBox _comboBox;
public LabeledComboBox()
{
this.DefaultStyleKey = typeof(LabeledComboBox);
}
public LabeledComboBox(List<Parameter> parameterList)
{
this.Label = parameterList[0].DisplayName ?? "";
this.ItemsSource = parameterList;
this.SelectedValuePath = "DefaultValue";
this.DisplayMemberPath = "DefaultValue";
this.SelectedIndex = 0;
this.DefaultStyleKey = typeof(LabeledComboBox);
}
protected override void OnApplyTemplate()
{
base.OnApplyTemplate();
_comboBox = GetTemplateChild("PART_ComboBox") as ComboBox;
if (_comboBox != null)
{
_comboBox.SelectionChanged += OnComboBoxSelectionChanged;
if (_comboBox.Items != null)
{
this.SelectedIndex = 0;
_comboBox.SelectedValue = _comboBox.Items[this.SelectedIndex];
}
}
}
private void OnComboBoxSelectionChanged(object sender, SelectionChangedEventArgs e)
{
this.SelectedValue = _comboBox.SelectedValue;
}
public string GetKey()
{
return Label;
}
public string GetValue()
{
return SelectedValue.ToString();
}
}
It will be called in two different ways:
Dynamically in C#:
stackPanel.Add(new LabeledComboBox(parameterList));
Static in Xaml:
<templates:LabeledComboBox Label="Kategorien:" ItemsSource="{Binding ElementName=pageRoot, Path=FeedCategories}" DisplayMemberPath="Name" SelectedValuePath="Name" />
As I said before I got two issues with it:
How can I bind the SelectionChangedEvent to access it in Xaml || C#
As you can see, I try to preselect the first Item, which does not work and I don't know how to do it right
Thank you very much for all helpful and well meant answers in advance!
Instead of creating a custom control and recreating all needed dependency properties, I would suggest you use the Header and HeaderTemplate properties of the built in ComboBox, which will be displayed, just like in your LabeledComboBox, above the selection menu. Additionally the SelectionChanged event will be available.
So the usage in XAML would look like the following:
<ComboBox
DisplayMemberPath="Name"
Header="Kategorien:"
ItemsSource="{Binding ElementName=pageRoot, Path=FeedCategories}"
SelectedValuePath="Name"
SelectionChanged="OnSelectionChanged">
<ComboBox.HeaderTemplate>
<DataTemplate>
<TextBlock
Margin="10,0"
VerticalAlignment="Center"
FontWeight="Bold"
Text="{Binding}" />
</DataTemplate>
</ComboBox.HeaderTemplate>
</ComboBox>
But if you don't want to use the above method, to expose the selection changed event in your LabeledComboBox, add the following code:
private void OnComboBoxSelectionChanged(object sender, SelectionChangedEventArgs e)
{
this.SelectedValue = _comboBox.SelectedValue;
this.RaiseSelectionChanged(e);
}
public event EventHandler<SelectionChangedEventArgs> SelectionChanged;
private void RaiseSelectionChanged(SelectionChangedEventArgs args)
{
if (SelectionChanged != null)
{
SelectionChanged(this, args);
}
}
Then you can use the created SelectionChanged event from XAML.

How to reuse a UserControl in situations where the DataContext is slightly different?

This is my first post on StackOverflow and also my first Question.
I had created a UserControl in WPF with the MVVM Pattern (called Block).
This UserControl should be used in another UserControl, as DataTemplate of a ListBox (called Sector).
The Block Control should be used as standalone and as DataTemplate for different UserControls.
If I set the DataContext in the View of Block, the standalone Version works great, but not as part of the Sector View.
If I don´t set the DataContext in the View of Block, it works in Sector but don’t standalone.
My question is, is it the only way to leave the DataContext in the View of Block and set it in the View I used the Control or the ViewModel?
Here is my Code:
Model of Block:
public class BlockModel : ModelBase
{
#region private Variables
string blockName = "Block";
string blockContent = "00000";
#endregion private Variables
#region Properties
public string BlockName
{
get { return blockName; }
set { blockName = value; NotifyPropertyChange("BlockName "); }
}
public string BlockContent
{
get { return blockContent; }
set { blockContent = value; NotifyPropertyChange("BlockContent"); }
}
#endregion Properties
#region ctor
public BlockModel () { }
#endregion ctor
}
ViewModel of Block:
public class BlockViewModel : ViewModelBase
{
#region private Variables
string charToFill = "0";
DelegateCommand fillWithChar;
BlockModel dataModel = new BlockModel();
#endregion private Variables
#region Properties
public Models. BlockModel DataModel
{
get { return dataModel; }
set { dataModel = value; }
}
public string BlockContent
{
get { return dataModel. BlockContent; }
set
{
if (dataModel. BlockContent != value)
{
dataModel. BlockContent = value;
NotifyPropertyChange ("BlockContent");
}
}
}
public string BlockName
{
get { return dataModel. BlockName; }
set
{
if (dataModel. BlockName != value)
{
dataModel. BlockName = value;
NotifyPropertyChange("BlockName");
}
}
}
public string CharToFill
{
get { return charToFill; }
set
{
if (charToFill != value)
{
charToFill = value;
NotifyPropertyChange ("CharToFill");
}
}
}
public ICommand FillWithChar
{
get
{
if (fillWithChar == null)
fillWithChar = new DelegateCommand(FillText);
return fillWithChar;
}
}
#endregion Properties
#region ctor
public BlockViewModel()
{
}
#endregion ctor
#region Methods
private void FillText()
{
CodingBlockContent = CodingBlockContent.PadLeft(32, charToFill[0]);
}
#endregion Methods
}
View of Block:
<UserControl x:Class="…./Block"
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"
xmlns:local="clr-namespace:…/Controls"
mc:Ignorable="d" d:DesignWidth="460" d:DesignHeight="44">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="124" />
<ColumnDefinition Width="301" />
<ColumnDefinition Width="30"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="30"></RowDefinition>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0" Text="{Binding BlockName}"
HorizontalAlignment="Left" VerticalAlignment="Center" FontSize="14" Margin="2,6"/>
<ComboBox FontFamily="Consolas" Grid.Row="00" Grid.Column="1"
Text="{Binding BlockContent, Mode=TwoWay}"
Tag="{Binding BlockName}" Name="cbxBlock" FontSize="14"
HorizontalAlignment="Left" VerticalAlignment="Center" Width="290" Margin="1,4,0,5" IsEditable="True" Height="26">
<ComboBoxItem Content=""></ComboBoxItem>
<ComboBoxItem Content="0000000000000"></ComboBoxItem>
<StackPanel HorizontalAlignment="Left" VerticalAlignment="Top" Orientation="Horizontal">
<TextBox Margin="10,2,0,2" Text="0" Width="24" FontSize="14" Name="tbxChar" MaxLength="1"></TextBox>
<TextBlock Margin="10,2,0,2" Text="auffüllen" VerticalAlignment="Center" FontSize="14"></TextBlock>
<Button Margin="10,2,0,2" Content="Ausführen" Width="100" Command="{Binding FillWithChar}"></Button>
</StackPanel>
</ComboBox>
<TextBlock Grid.Row="0" Width="30" Grid.Column="2" Text="{Binding CodingBlockContent.Length}"
HorizontalAlignment="Left" VerticalAlignment="Center" FontSize="14" Margin="2,6,0,6" Grid.ColumnSpan="2"/>
</Grid>
Model of Sector:
public class SectorModel
{
#region private Variables
int blockAmount = 4;
string sectorNumber = "Sektor";
int blockBegin = 0;
bool isSectorInUse = false;
#endregion private Variables
#region Properties
public string SectorNumber
{
get { return sectorNumber; }
set { sectorNumber = value;}
}
public int BlockBegin
{
get { return blockBegin; }
set
{
blockBegin = value;
}
}
public bool IsSectorInUse
{
get { return isSectorInUse; }
set { isSectorInUse = value;}
}
public int BlockAmount
{
get { return blockAmount; }
set
{
blockAmount = value;;
}
}
#endregion Properties
public SectorModel()
{
}
}
ViewModel of Sector:
public class SectorViewModel : ViewModelBase
{
#region private Variables
SectorModel dataModel = new SectorModel();
ObservableCollection<BlockViewModel> sectorBlocks = new ObservableCollection<BlockViewModel>();
#endregion private Variables
#region Properties
public SectorModel DataModel
{
get { return dataModel; }
set { dataModel = value; }
}
public ObservableCollection<BlockViewModel> SectorBlocks
{
get { return sectorBlocks; }
set { sectorBlocks = value; NotifyPropertyChange ("SectorBlocks"); }
}
public string SectorNumber
{
get { return "Sektor " + DataModel.SectorNumber; }
set { DataModel.SectorNumber = value; NotifyPropertyChange ("SectorNumber"); }
}
public int BlockBegin
{
get { return DataModel.BlockBegin; }
set
{
DataModel.BlockBegin = value;
SetBlocks();
OnPropertyChanged("BlockBegin");
}
}
public bool IsSectorInUse
{
get { return DataModel.IsSectorInUse; }
set { DataModel.IsSectorInUse = value; NotifyPropertyChange ("IsSectorInUse"); }
}
public int BlockAmount
{
get { return DataModel.BlockAmount; }
set
{
DataModel.BlockAmount = value;
SetBlocks();
NotifyPropertyChange ("CodingBlockAmount");
}
}
#endregion Properties
void SetBlocks()
{
while (SectorBlocks.Count != BlockAmount)
{
SectorBlocks.Add(new BlockViewModel());
}
int begin = BlockBegin;
foreach (BlockViewModel block in SectorBlocks)
{
block.CodingBlockName = "Block " + begin.ToString().PadLeft(2, '0');
block++;
}
}
public SectorViewModel()
{
SetBlocks();
}
}
View of Sector:
<UserControl xmlns:Views="clr-namespace:…/RFIDControls" x:Class="…/Sector"
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"
d:DesignHeight="300" d:DesignWidth="473">
<Border BorderBrush="Black" BorderThickness="0,0,0,1">
<Expander Name="expMain" Margin="0,0,4,0">
<Expander.Header>
<Grid Name="grdHeader">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100" />
<ColumnDefinition Width="300" />
<ColumnDefinition Width="30" />
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0" Grid.Row="0" Height="24" Text="{Binding SectorNumber}" HorizontalAlignment="Left" VerticalAlignment="Center" FontSize="14" FontWeight="Bold" Panel.ZIndex="98"/>
<CheckBox Grid.Column="2" VerticalAlignment="Center" IsChecked="{Binding IsSectorInUse}"></CheckBox>
</Grid>
</Expander.Header>
<Grid>
<ListBox ItemsSource="{Binding SectorBlocks}" Name="listBox">
<ListBox.ItemTemplate>
<DataTemplate DataType="{x:Type Views:BlockViewModel}">
<Views:Block/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Expander>
</Border>
Thank you.
With kind regards from Germany
Dominik
PS: I hope my English is not so bad as I suppose
This is a common problem for new users of WPF. You have two possible solutions. When using MVVM, you shouldn't need to set the DataContext of the UserControl anywhere. Instead, you can simply add a DataTemplate to your App.xaml to make the pairing:
<DataTemplate DataType="{x:Type ViewModels:BlockViewModel}">
<Views:BlockView />
</DataTemplate>
In this way, whenever you show an instance of your BlockViewModel, the Framework will display the related BlockView instead (like you have done in your SectorView class).
The alternative option is to not use MVVM for the UserControl (use Bindable DependencyPropertys instead), to not set its DataContext internally and to use RelativeSource Bindings on the elements inside instead:
<TextBlock Grid.Row="0" Grid.Column="0" Text="{Binding DataContext.BlockName,
RelativeSource={RelativeSource AncestorType={
x:Type YourXmlNamespacePrefix:BlockView}}}" HorizontalAlignment="Left"
VerticalAlignment="Center" FontSize="14" Margin="2,6"/>
Using this method, the RelativeSource Binding will look at whatever object is currently set as the DataContext.
Sounds like Block act as an control, which seems participate in other usercontrol or part of Template, in my opinion, mvvm doesn't work in here, you should use Dependency property instead.
Forgive my poor english.

refreshing a Combobox after the ItemSource changes in my view model

I have a combobox that need to be populated based on the selection of another combobox.
When i set the Mode to TwoWay, i get am exception stating the Property QueryNames is ReadOnly. I have spent hours on this issue now. am i doing the right thing? any ideas?
My view looks like this:
<StackPanel Orientation="Horizontal" Height="Auto" Name="stackPanel1" Width="Auto" Grid.Row="1">
<Label Content="Select Module:" Height="30" Name="labelModule" Width="Auto"></Label>
<ComboBox Height="24" Name="comboBoxModule" Width="150" ItemsSource="{Binding QueryModules}" SelectedItem="{Binding SelectedQueryModule}" SelectionChanged="comboBoxModule_SelectionChanged" />
<Label Content="Select the query you wish to run:" Height="30" Name="labelQuery" Width="Auto" Visibility="Collapsed" />
<ComboBox Height="Auto" Name="comboBoxQuery" Width="300" IsEditable="True" ItemsSource="{Binding QueryNames, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" SelectedItem="{Binding SelectedQueryNames, Mode=TwoWay}" SelectedValuePath="Key" DisplayMemberPath="Value" Visibility="Collapsed" />
<Button Content="Run Query" Height="23" Name="ButtonQuery" Width="75" Visibility="Collapsed"/>
</StackPanel>
My view model is here:
public QueriesViewModel()
{
_service = new QueriesService();
var queryModules = _service.GetQueryGroups();
m_queryModules = new ObservableCollection<string>(queryModules);
m_ReadOnlyQueryModules = new ReadOnlyObservableCollection<string>(m_queryModules);
}
private readonly IQueriesService _service;
#region QueryModules
private readonly ObservableCollection<string> m_queryModules;
private readonly ReadOnlyObservableCollection<string> m_ReadOnlyQueryModules;
private string m_SelectedQueryModule;
public string SelectedQueryModule
{
get
{
return m_SelectedQueryModule;
}
set
{
if (m_SelectedQueryModule != value)
{
m_SelectedQueryModule = value;
OnPropertyChanged("SelectedQueryModule");
var queryNames = _service.GetQueryNames(m_SelectedQueryModule);
m_queryNames = new Dictionary<int, string>(queryNames);
m_ReadOnlyQueryNames = new Dictionary<int, string>(m_queryNames);
OnPropertyChanged("SelectedQueryNames");
//this.QueryNames = m_ReadOnlyQueryNames; //NOTE: Unable to do this, throws an exception stating the QueryNames property is read only.
}
}
}
public ReadOnlyObservableCollection<string> QueryModules { get { return m_ReadOnlyQueryModules; } }
#endregion
#region QueryNames
private Dictionary<int, string> m_queryNames;
private Dictionary<int, string> m_ReadOnlyQueryNames;
private string m_SelectedQueryNames;
public string SelectedQueryNames
{
get
{
return m_SelectedQueryNames;
}
set
{
if (m_SelectedQueryNames != value)
{
m_SelectedQueryNames = value;
OnPropertyChanged("SelectedQueryNames");
}
}
}
public Dictionary<int, string> QueryNames { get { return m_ReadOnlyQueryNames; } }
#endregion
I think you only need to raise PropertyChanged event for QueryNames property
if (m_SelectedQueryModule != value)
{
m_SelectedQueryModule = value;
OnPropertyChanged("SelectedQueryModule");
var queryNames = _service.GetQueryNames(m_SelectedQueryModule);
m_queryNames = new Dictionary<int, string>(queryNames);
//RAISE PROPERTY CHANGED AFTER YOU SET NEW VALUE FOR m_queryNames
OnPropertyChanged("QueryNames");
m_ReadOnlyQueryNames = new Dictionary<int, string>(m_queryNames);
OnPropertyChanged("SelectedQueryNames");
}

Custom UserControl with ContentControl field

I have a UserControl which acts as a wrapper for a ContentControl, which is simply a title to the ContentControl.
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Background="Green" Grid.Row="0">
<TextBlock Text="{Binding Header}" Style="{StaticResource HeaderStyle}" Margin="12, 10, 0, 10" />
</Grid>
<ContentControl HorizontalAlignment="Stretch" HorizontalContentAlignment="Stretch" Content="{Binding Body}" Grid.Row="1"/>
</Grid>
And here's where I try to use the control:
<gbl:ListHeader Grid.Row="1" Visibility="{Binding HasMovies, Converter={StaticResource VisibilityConverter}}" Header="{Binding Path=LocalizedResources.movie_list_header, Source={StaticResource LocalizedStrings}}" >
<gbl:ListHeader.Body>
<ListBox SelectionChanged="ListBoxContainerSelectionChanged" ItemsSource="{Binding Movies}" ItemContainerStyle="{StaticResource HeaderListBoxItemStyle}">
<ListBox.ItemTemplate>
<DataTemplate>
<gbl:MovieItemControl Header="{Binding MovieTitle}" Description="{Binding FormattedDescription}" Detail="{Binding FormattedDetail}" Opacity="{Binding IsSuppressed, Converter={StaticResource DimIfTrueConverter}}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</gbl:ListHeader.Body>
The DataBinding to the list happens, however nothing displays in the control. I'm guessing that it's still there, but too small to see (undefined h/w).
Is there something that I'm doing wrong? The header shows fine, so the control appears to be working somewhat.
Edit:
Here's the code-behind for ListHeader:
public partial class ListHeader : UserControl
{
private readonly ListHeaderData _data = new ListHeaderData();
public ListHeader()
{
InitializeComponent();
DataContext = _data;
}
public string Header
{
get { return (string)GetValue(HeaderProperty); }
set { SetValue(HeaderProperty, value); }
}
// Using a DependencyProperty as the backing store for Header. This enables animation, styling, binding, etc...
public static readonly DependencyProperty HeaderProperty =
DependencyProperty.Register("Header", typeof(string), typeof(ListHeader), new PropertyMetadata("",HeaderPropertyChanged) );
private static void HeaderPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var lh = d as ListHeader;
if (lh != null)
lh._data.Header = e.NewValue as string;
}
public object Body
{
get { return GetValue(BodyProperty); }
set { SetValue(BodyProperty, value); }
}
// Using a DependencyProperty as the backing store for Body. This enables animation, styling, binding, etc...
public static readonly DependencyProperty BodyProperty =
DependencyProperty.Register("Body", typeof(object), typeof(ListHeader), new PropertyMetadata(null, BodyPropertyChanged));
private static void BodyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var lh = d as ListHeader;
if (lh != null)
lh._data.Body = e.NewValue;
}
}
public class ListHeaderData : ViewModelBase
{
public ListHeaderData()
{
if (IsInDesignMode)
{
Header = "Custom Header Goes Here";
Body = new Grid() { Background = new SolidColorBrush(Colors.Yellow) };
}
}
private string _header;
public string Header
{
get { return _header; }
set { _header = value; RaisePropertyChanged("Header"); }
}
private object _body;
public object Body
{
get { return _body; }
set { _body = value; RaisePropertyChanged("Body");}
}
}
In addition to what i said in my comment you appear to bind to your DataContext in the UserControl declaration which is a Bad Thing and the problem of all this.
You appear to want to bind to the properties of the UserControl but you bind directly to the properties of the DataContext which is your ViewModel, hence setting the Body property on an instance in XAML does nothing as the property is sidestepped by the internal binding.
UserControls should for all i know do bindings like this:
<UserControl Name="control" ...>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid Background="Green" Grid.Row="0">
<TextBlock Text="{Binding Header, ElementName=control}" Style="{StaticResource HeaderStyle}" Margin="12, 10, 0, 10" />
</Grid>
<ContentControl HorizontalAlignment="Stretch" HorizontalContentAlignment="Stretch" Content="{Binding Body, ElementName=control}" Grid.Row="1"/>
</Grid>
Get rid of those dependency property changed callbacks and change the property code in ViewModels to this format to make sure it changed:
private int _MyProperty = 0;
public int MyProperty
{
get { return _MyProperty; }
set
{
if (_MyProperty != value)
{
_MyProperty = value;
OnPropertyChanged("MyProperty");
}
}
}

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