Button in Tracker?

[redundancer]

Is it possible to add a button with OnClick/ Command functionality to a tracker? If yes, how?

I am panning to have a button in the tracker of a ScatterSeries. If you click the button, another plot will be visible with more information about the point.

Thanks in advance!

[VisualMelon]

It may be possible with some platforms, e.g. there are examples for custom trackers for WPF: https://github.com/oxyplot/oxyplot/blob/develop/Source/Examples/WPF/WpfExamples/Examples/CustomTrackerDemo/MainWindow.xaml

Note that you'll need a custom plot controller in order to keep the tracker open after clicking: https://github.com/oxyplot/oxyplot/blob/899ea5b3baf3d2010680f2e607ad5281e3f190e5/Source/Examples/WPF/SimpleDemo/CustomPlotController.cs

In general, may be best to handle clicking of the series manually without the tracker, as it sounds like you won't really be using it as a tracker any more, and that should be achievable on any platform (WinForms, for example, doesn't support custom trackers)

[redundancer]

Also not in the surrounding UserControl:

    <UserControl.Resources>
        <Style TargetType="oxy:TrackerControl">
            <Setter Property="IsHitTestVisible" Value="True" />
        </Style>
    </UserControl.Resources>

[VisualMelon]

I think the problem is that the tracker is below the invisible interaction pane that sits on top of the plot. This may make this rather more difficult than I'd thought.

Yeah, the tracker is put in the overlays part of the PlotView, which is below a transparent mouseGrid that which eats all user input:

oxyplot/Source/OxyPlot.Wpf.Shared/PlotViewBase.cs

Lines 178 to 206 in 196bb74

	public override void OnApplyTemplate()
	{
	base.OnApplyTemplate();
	this.grid = this.GetTemplateChild(PartGrid) as Grid;
	if (this.grid == null)
	{
	return;
	}
	this.plotPresenter = this.CreatePlotPresenter();
	this.grid.Children.Add(this.plotPresenter);
	this.plotPresenter.UpdateLayout();
	this.renderContext = this.CreateRenderContext();
	this.overlays = new Canvas();
	this.grid.Children.Add(this.overlays);
	this.zoomControl = new ContentControl();
	this.zoomControl.Focusable = false;
	this.overlays.Children.Add(this.zoomControl);
	// add additional grid on top of everthing else to fix issue of mouse events getting lost
	// it must be added last so it covers all other controls
	var mouseGrid = new Grid
	{
	Background = Brushes.Transparent // background must be set for hit test to work
	};
	this.grid.Children.Add(mouseGrid);
	}

Off-hand, I can't think how to get around this...

[redundancer]

Oh no :( Thank you very much for your effort!

[VisualMelon]

The commit that added the transparent overlay is from #382

I did some tests, and moving the overlays in front of the mouseGrid didn't seem to cause any issues for me... so it may be enough to just swap them over. This of course may lead to issues with updates as described in #382, but maybe that's acceptable for your use-case (I don't understand #382, so won't try to predict what will happen). This could be done by overriding OnApplyTemplate on PlotView and swapping the last 2 children of the grid after calling the base (or I vaguely recall WPF has Z-index support within panels, but again been a while). This combined with setting IsHitTsetVisible on TrackerControl should be enough, based on some rough testing.

Obviously overloading PlotView is a bit of a pain: can always bodge it if necessary e.g. by hooking something that will be called after OnApplyTemplate.

[redundancer]

Thank you so much! I tried around a lot and it seems like removing the mouseGrid solves my problem. Every functionality i need still works and I can live with not recognizing click events during InvalidatePlot() as described in #382. I will post an answer with all details in case someone else wants to do same thing as me.

[redundancer]

With a lot of help from @VisualMelon I finally managed to create a tracker with working buttons inside. To summarize:

1. To avoid closing of the tracker after release of the left mouse button I created a TrackerManipulator:

internal class StaysOpenTrackerManipulator : OxyPlot.TrackerManipulator
  {
      public StaysOpenTrackerManipulator(IPlotView plotView) : base(plotView)
      {
          Snap = true;
          PointsOnly = true;
      }

      public override void Started(OxyMouseEventArgs e)
      {
           /*
             * Close tracker when clicking. This avoids wrong shaping of the tracker
             * in case it's text is of different length for different points. Additionally,
             * one can close the tracker like this by clicking somewhere else.
             */
          PlotView.HideTracker();
          base.Started(e);
      }

      public override void Completed(OxyMouseEventArgs e)
      {
          // Do nothing to avoid tracker closing.
      }
  }

and add it to the plot controller:

CustomPlotController.BindMouseDown(mouseButton, new DelegatePlotCommand<OxyMouseDownEventArgs>((view, controller, args) =>
                controller.AddMouseManipulator(view, new StaysOpenTrackerManipulator(view), args)));

2. A transparent mouseGrid that is on top of the tracker prevents the tracker control to recognize hits. Removing that mouseControl solved it for me, but it may cause problems described here OxyMouseEvents not caught due to InvalidatePlot() #382. Hence I created my own very simple PlotView:

public class RtpOptimizationPlotView : PlotView
    {
        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            grid.Children.RemoveAt(grid.Children.Count - 1);
        }
    }

3. Add the custom plot view to a user control or so and define the trackercontrol. Note that it is important to set IsHitTestVisible="True" for TrackerControl and point to the correct DataContext for the Buttons' commands:

<UserControl 
    ...
    x:Name="RtOptimizationUserControl">
<views:RtpOptimizationPlotView
      Model="{Binding OptimizationPlotModel, Mode=TwoWay}"
      Controller="{Binding CustomPlotController}">
      <views:RtpOptimizationPlotView.DefaultTrackerTemplate>
          <ControlTemplate>
              <oxy:TrackerControl
                  IsHitTestVisible="True"
                  Position="{Binding Position}" LineExtents="{Binding PlotModel.PlotArea}"
                  BorderThickness="1">
                  <oxy:TrackerControl.Background>
                      <SolidColorBrush Color="LightBlue" />
                  </oxy:TrackerControl.Background>
                  <oxy:TrackerControl.Content>
                      <StackPanel Orientation="Vertical">
                          <TextBlock Text="{Binding}" Margin="7"/>
                          <StackPanel Orientation="Horizontal">
                              <Button 
                                  Command="{Binding DataContext.FirstButtonsCommand, ElementName=RtOptimizationUserControl}">Button 1</Button>
                              <Button
                                  Command="{Binding DataContext.SecondButtonsCommand, ElementName=RtOptimizationUserControl}">Button 2</Button>
                          </StackPanel>
                      </StackPanel>
                  </oxy:TrackerControl.Content>
              </oxy:TrackerControl>
          </ControlTemplate>
      </views:RtpOptimizationPlotView.DefaultTrackerTemplate>
  </views:RtpOptimizationPlotView>
</UserControl>

Thanks a lot to @VisualMelon for all your help!

[VisualMelon]

Thanks for providing this write-up: will be very useful for other people in future to have it clearly presented in one place like this.