I have an ObservableCollection of ViewModels in my main ViewModel. The binding seems to work fine since I can switch views. However, raising the ViewModelBase OnPropertyChanged method (which work for other stuff) in an element of the ObservableCollection result in a null PropertyChanged value in ViewModelBase.
Here's my main code snippets:
In my main ViewModel Constructor:
public EditorViewModel()
{
base.DisplayName = Strings.EditorName;
_availableEditors = new ObservableCollection<ViewModelBase>();
AvailableEditors.Add(new GBARomViewModel(646, 384));
AvailableEditors.Add(new MonsterViewModel(800, 500));
CurrentEditor = _availableEditors[0];
}
At GBA ROM loading, ViewModel and Model properties are updated:
void RequestOpenRom()
{
OpenFileDialog dlg = new OpenFileDialog();
dlg.DefaultExt = ".gba";
dlg.Filter = "GBA ROM (.gba)|*.gba|All files (*.*)|*.*";
dlg.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
Nullable<bool> result = dlg.ShowDialog();
if (result == true)
{
if(CurrentEditor is GBARomViewModel)
{
(CurrentEditor as GBARomViewModel).ReadRom(dlg.FileName);
}
}
}
In my main View: Variation of TabControl (to have view switching and view states preservation).
<controls:TabControlEx ItemsSource="{Binding AvailableEditors}"
SelectedItem="{Binding CurrentEditor}"
Style="{StaticResource BlankTabControlTemplate}"
MinWidth="{Binding CurrentEditorWidth}"
MinHeight="{Binding CurrentEditorHeight}"
MaxWidth="{Binding CurrentEditorWidth}"
MaxHeight="{Binding CurrentEditorHeight}"
Width="{Binding CurrentEditorWidth}"
Height="{Binding CurrentEditorHeight}"
HorizontalAlignment="Left"
VerticalAlignment="Top">
<controls:TabControlEx.Resources>
<DataTemplate DataType="{x:Type vm:GBARomViewModel}">
<vw:GBARomView />
</DataTemplate>
<DataTemplate DataType="{x:Type vm:MonsterViewModel}">
<vw:MonsterView />
</DataTemplate>
</controls:TabControlEx.Resources>
</controls:TabControlEx>
In GBARomViewModel (child ViewModel, element of AvailableEditors)
public String CRC32
{
get
{
return _rom.CRC32;
}
set
{
if (value.Equals(_rom.CRC32))
{
return;
}
_rom.CRC32 = value;
OnPropertyChanged("CRC32");
}
}
Property binding in child View
Now this is a UserControl so I'll put its code as well after. Other properties at startup work such as LabelWidth and the LabelValue. Giving a default value to TextBoxValue in XAML also work.
<StackPanel VerticalAlignment="Bottom" HorizontalAlignment="Left" Margin="10, 0, 0, 10" Width="300">
<dlb:DefaultLabelBox LabelWidth="82" TextBoxWidth="100" HorizontalAlignment="Left" LabelValue="{x:Static p:Strings.RomTitle}" TextBoxValue="{Binding Title}" />
<dlb:DefaultLabelBox LabelWidth="82" TextBoxWidth="100" HorizontalAlignment="Left" LabelValue="{x:Static p:Strings.RomGameCode}" TextBoxValue="{Binding GameCode}" />
<dlb:DefaultLabelBox LabelWidth="82" TextBoxWidth="100" HorizontalAlignment="Left" LabelValue="{x:Static p:Strings.RomRomSize}" TextBoxValue="{Binding RomSize}" />
<dlb:DefaultLabelBox LabelWidth="82" TextBoxWidth="100" HorizontalAlignment="Left" LabelValue="{x:Static p:Strings.RomCRC32}" TextBoxValue="{Binding CRC32}" />
<dlb:DefaultLabelBox LabelWidth="82" TextBoxWidth="200" HorizontalAlignment="Left" LabelValue="{x:Static p:Strings.RomMD5Checksum}" TextBoxValue="{Binding MD5Checksum}"/>
</StackPanel>
DefaultLabelBox.cs
<UserControl x:Name="uc">
<StackPanel>
<TextBlock Text="{Binding Path=LabelValue, ElementName=uc}"
Width="{Binding Path=LabelWidth, ElementName=uc}"/>
<Label Content="{Binding Path=TextBoxValue, Mode=OneWay, ElementName=uc}"
Width="{Binding Path=TextBoxWidth, ElementName=uc}"/>
</StackPanel>
</UserControl>
DefaultLabelBox.xaml.cs
public string TextBoxValue
{
get {
return (string)GetValue(TextBoxValueProperty);
}
set {
SetValue(TextBoxValueProperty, value);
}
}
public static readonly DependencyProperty TextBoxValueProperty =
DependencyProperty.Register("TextBoxValue", typeof(string), typeof(DefaultLabelBox), new PropertyMetadata(default(string)));
Control Template
<Style TargetType="dlb:DefaultLabelBox">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="dlb:DefaultLabelBox">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding LabelValue, RelativeSource={RelativeSource TemplatedParent}}"
MinWidth="20"
Width="{Binding LabelWidth, RelativeSource={RelativeSource TemplatedParent}}"
VerticalAlignment="Center"
FontFamily="Mangal"
Height="20"
FontSize="13"/>
<Label Content="{Binding TextBoxValue, Mode=OneWay, RelativeSource={RelativeSource TemplatedParent}}"
BorderBrush="{StaticResource DefaultLabelBoxBorderBrush}"
BorderThickness="1"
Padding="1,1,1,1"
Background="{StaticResource DefaultLabelBoxBackgroundBrush}"
Foreground="{StaticResource DefaultLabelBoxForeground}"
MinWidth="60"
Height="20"
VerticalAlignment="Center"
FontFamily="Mangal"
Width="{Binding TextBoxWidth, RelativeSource={RelativeSource TemplatedParent}}"
FontSize="13"/>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
I tried a few things but being new to MVVM I don't know if I have a DataContext issue of a binding one. Any help would be appreciated.
Edit: I made changes to some code to illustrate the working solution for me as well as adding the ControlTemplate I had forgot. I'm not sure if Mode=OneWay is mandatory in UserControl and ControlTemplate but it's working now so I'm leaving it as it is.
