After DrawLine() what is the selected object?

[dontpanic]

Hi,

After I have drawn several objects on the chart such as using DrawLine(), and the user clicks on one of the lines to select it, how do get the tag of the selected object? Is it part of IDrawObject?

Thanks,
Will.

[NinjaTrader_Bertrand]

That's correct Will, the identification would be done over the tag id - https://www.ninjatrader.com/support/...rawobjects.htm

[dontpanic]

Thanks I had missed that information.

Still, I haven't been able to work out firstly how to identify if an object is selected, and then how to delete it. Correction... I guess RemoveDrawObject() would delete it, so I just need to know how to identify the selection.

Thanks,
will.

[koganam]

Thanks I had missed that information.

Still, I haven't been able to work out firstly how to identify if an object is selected, and then how to delete it. Correction... I guess RemoveDrawObject() would delete it, so I just need to know how to identify the selection.

Thanks,
will.

You would have to use unsupported direct C# mouse methods.

[dontpanic]

Hi Koganam,

Mouse Methods? Can you give me more of a hint?

Are you suggesting that I write a method that detects whether my mouse click is in the 'zone' of any part of my draw object? If thats the case that would mean writing a different method for every type of draw object, and for objects like circles, arcs etc that could be very complicated.

Surely there would be a 'selected' property or method somewhere, after all some part of NT has to know that the object is selected so that it can draw the selection corners?

Will.

[koganam]

Hi Koganam,

Mouse Methods? Can you give me more of a hint?

Are you suggesting that I write a method that detects whether my mouse click is in the 'zone' of any part of my draw object? If thats the case that would mean writing a different method for every type of draw object, and for objects like circles, arcs etc that could be very complicated.

Pretty much.

Surely there would be a 'selected' property or method somewhere, after all some part of NT has to know that the object is selected so that it can draw the selection corners?

Will.

That is buried deep in the core of NT, not exposed.

[AlBundy]

Delete manually a selected draw object from the chart.

Hi,

After I have drawn several objects on the chart such as using DrawLine(), and the user clicks on one of the lines to select it, how do get the tag of the selected object? Is it part of IDrawObject?

Thanks,
Will.

This is the code how I do it and it works perfect - I check if the selected object is either Line or Text. The others remain - I need it like this in my code. You can remove the switch and execute the code in the case section.

public void deleteSelectedObject()
{
            Type chartControlType = typeof(ChartControl);
            FieldInfo fi = chartControlType.GetField("selectedObject", BindingFlags.NonPublic | BindingFlags.Instance);
            if ( fi != null )
            {
                if ( fi.GetValue(ChartControl) != null )
                {
                    // an object is selected!
                    IDrawObject clickedObject = (IDrawObject) fi.GetValue(ChartControl);
                    switch ( clickedObject.DrawType )
                    {
                        case DrawType.Line:
                        case DrawType.Text:
                            RemoveDrawObject(clickedObject);
                            break;
                    }
                    Print("Deleted Type=" + clickedObject.DrawType.ToString() + " Tag=" + clickedObject.Tag);
                    // I have to notify NinjaTrader that the object has been removed otherwise it remains in NTs internal structure!
                    ChartControl.ChartPanel.Focus();
                    SendKeys.Send("{ESC}");
                    ChartControl.Invalidate();
                    ChartControl.Refresh();
                }
            }
}

Remember: There is no other way to delete a draw object from the chart which has been added by an indicator. When you try to delete it you receive the message that the indicator, which created the draw object, will be removed as well. You can delete with this method only draw objects created by the indicator which is running the above code.

Also consider with this method you cannot delete a selected manual draw object!

[ninZa]

Remember: There is no other way to delete a draw object from the chart which has been added by an indicator. When you try to delete it you receive the message that the indicator, which created the draw object, will be removed as well. You can delete with this method only draw objects created by the indicator which is running the above code.

Also consider with this method you cannot delete a selected manual draw object!

Thank you for your post.
What about this solution: AllowRemovalOfDrawObjects

http://www.ninjatrader.com/support/helpGuides/nt7/index.html?allowremovalofdrawobjects.htm

// Initialize method of a custom indicator
protected override void Initialize()
{
Add(new Plot(Color.Orange, "SMA"));
AllowRemovalOfDrawObjects = true; // Draw objects can be removed separately from the script
}

Alternatively, you can set the "Locked" property of the draw object to False to enable manual change / removal of the object. For example:

ChartLine line = (ChartLine)DrawLine(...);
line.Locked = false;