oaz/avaloniagraphcontrol

A graph layout panel for AvaloniaUI

avaloniagraphcontrol's Issues

How do I move nodes with the mouse?

'A 'Binding' cannot be set on the 'Source' property of type 'GraphView'.

State Machine Many Composites (Horizontal) in the sample app crashes sometimes

State Machine Many Composites (Horizontal) in the sample app crashes sometimes. Exception comes from MSAGL. I'm using the latest version of MSAGL from github.

The crash doesn't happen every time I select this graph, but it happens often.

Proposal to add ability to use a different brush for some edges

Hi.

I want to be able to color some edges in my graph differently. I've found that it's possible to change the color of all edges using Styles, but I haven't figured out how to color an edge separately. Please enlighten me, if you have the solution.

If not, I propose that we expand the Edge class to take a brush color and use that in the Connection class for setting the Brush property. I can submit a pull request if you think it's a good idea. Please say so if you think another approach is needed.

Regards, Kristian.

Context menu for edges

I would like to add a context menu to remove edges.
I'm not sure if it is the best way, but I added this to the GraphPanel:

<agc:GraphPanel.DataTemplates>
	<DataTemplate DataType="{x:Type agc:Edge}">
		<agc:Connection>
			<agc:Connection.ContextMenu>
				<ContextMenu>
					<MenuItem Command="{Binding $parent.DataContext.RemoveEdge}" CommandParameter="{Binding}" Header="Remove edge"/>
				</ContextMenu>
			</agc:Connection.ContextMenu>
		</agc:Connection>
	</DataTemplate>
</agc:GraphPanel.DataTemplates>

The binding to a method works if I use the code behind and Click="MyMethod", but how do I bind to a view model method (with the xaml above, the context menu item is disabled)?
When I use Command="{Binding RemoveEdge}", the menu item is enabled, but the viewmodel method doesn't get called.

I need to pass the edge somehow as parameter. With the code behind approach the Edge is the DataContext property of MenuItem (which is the sender:

public void MyMethod(object sender, Avalonia.Interactivity.RoutedEventArgs e)
{
}

Another question is if it is possible to specify the thickness of the connection line? I only saw a Brush property. Since the line is pretty thin it would be helpful to make it a bit thicker on hover.

Drag and Drop

In MSAGL, it allows you to drag and drop/ move the nodes around. With this it doesn't seem to let me. Is there anything I can add to allow me to do that?

Usage in ScrollViewer causes InvalidOperationException

Hi, thanks for this great project 👍 I just have an issue when using it as a child of ScrollViewer, e.g. when modifying MainWindow.xaml in the sample the following way:

...
    </StackPanel>
    <ScrollViewer Grid.Column="0" Grid.Row="1">
      <agc:GraphPanel Background="WhiteSmoke" Graph="{Binding SelectedItem, ElementName=graphs}" Zoom="{Binding Value, ElementName=zoomer}" LayoutMethod="{Binding SelectedItem, ElementName=layoutMethods}">
...
      </agc:GraphPanel>
    </ScrollViewer>
  </Grid>
...

The following exception is thrown:

System.InvalidOperationException
  HResult=0x80131509
  Message=Invalid size returned for Measure.
  Source=Avalonia.Layout
  StackTrace:
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Controls.Presenters.ScrollContentPresenter.MeasureOverride(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   at Avalonia.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   at Avalonia.Controls.Grid.MeasureOverride(Size constraint)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureOverride(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   at Avalonia.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   at Avalonia.Controls.Grid.MeasureOverride(Size constraint)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.LayoutHelper.MeasureChild(ILayoutable control, Size availableSize, Thickness padding)
   at Avalonia.Layout.LayoutHelper.MeasureChild(ILayoutable control, Size availableSize, Thickness padding, Thickness borderThickness)
   at Avalonia.Controls.Presenters.ContentPresenter.MeasureOverride(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.LayoutHelper.MeasureChild(ILayoutable control, Size availableSize, Thickness padding)
   at Avalonia.Controls.Primitives.VisualLayerManager.MeasureOverride(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.LayoutHelper.MeasureChild(ILayoutable control, Size availableSize, Thickness padding)
   at Avalonia.Layout.LayoutHelper.MeasureChild(ILayoutable control, Size availableSize, Thickness padding, Thickness borderThickness)
   at Avalonia.Controls.Border.MeasureOverride(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.Layoutable.MeasureOverride(Size availableSize)
   at Avalonia.Controls.Window.MeasureOverride(Size availableSize)
   at Avalonia.Controls.WindowBase.MeasureCore(Size availableSize)
   at Avalonia.Layout.Layoutable.Measure(Size availableSize)
   at Avalonia.Layout.LayoutManager.Measure(ILayoutable control)
   at Avalonia.Layout.LayoutManager.ExecuteInitialLayoutPass(ILayoutRoot root)
   at Avalonia.Controls.Window.Show()
   at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.Start(String[] args)
   at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime[T](T builder, String[] args, ShutdownMode shutdownMode)
   at AvaloniaGraphControlSample.Program.Main(String[] args) in C:\iolevel\playground\AvaloniaGraphControl\sample\Program.cs:line 13

I'll attach a PR which should fix it.