Context menu for multiple selection

GoDiagram (6 and previous)
1

Hello!

I understand that we can show the context menu for a GoObject by overriding OnContextClick. How can I control the context menu for multiple selection?

Thanks,

Pradip

2

If you can’t put the code on a particular GoObject class, perhaps because there is more than one class to which it would apply, you should associate the code with the GoView, by implementing a GoView.ObjectContextClicked event handler. And maybe a GoView.BackgroundContextClicked event handler too, depending on what you want your application to do.
Remember to set GoView.ContextClickSingleSelection to false.

3

I tried the following code. It works correctly except that I don’t want the MessageBox 2 appearing. What am I missing?

public partial class Form1 : Form
{
    private View view;
    private Fb fb;
    private Var var;

    public Form1()
    {
          InitializeComponent();
          InitGoObjects();
          Controls.Add(view);
    }

    private void InitGoObjects()
    {
          view = new View();
          view.Dock = DockStyle.Fill;
          view.ContextClickSingleSelection = false;

          fb = new Fb();
          fb.Initialize(null, 0, "Top", "Bottom", 4, 2);
          fb.Position = new PointF(40, 40);
          view.Document.Add(fb);

          var = new Var();
          var.Text = "foo";
          var.Position = new PointF(200, 80);
          view.Document.Add(var);
    }
}

public class Fb : GoGeneralNode
{
    public override bool OnContextClick(GoInputEventArgs evt, GoView view)
    {
          MessageBox.Show("1");
          return base.OnContextClick(evt, view);
    }
}

public class Var : GoText
{
    public override bool OnContextClick(GoInputEventArgs evt, GoView view)
    {
          MessageBox.Show("2");
          return base.OnContextClick(evt, view);
    }
}

public class View : GoView
{
    public View()
    {
          ObjectContextClicked += new GoObjectEventHandler(View_ObjectContextClicked);
    }

    void View_ObjectContextClicked(object sender, GoObjectEventArgs e)
    {
          foreach (GoObject obj in Selection)
              MessageBox.Show(obj.ToString());
    }
}

Thanks in advance.

Pradip

4

I thought you were implying you couldn’t put the context menu code in the individual classes. So you should only have your code in the view’s ObjectContextClicked event handler.

5

In the above code, each class - Fb and Var - have custom context menus. Also, if I select both Fb and Var, then I want to show a different context menu. Extending this further, if I have 3 different classes selected, the context menu will be different from all the previous ones. How can I achieve this?

Sorry if I have not been clear earlier. Please let me know if you need further clarification.

Thanks,

Pradip

6

That’s right – you need to put all the context-menu creating code in the view’s handler, because you apparently want to decide what to show based on the Selection. So you can’t have any in overrides of GoObject.OnContextClick.