Working around BackBrush.Opacity is in read-only mode

[GARZONJ]

I have found and read the following post regarding this topic:
https://ninjatrader.com/support/foru...read-only-mode

It is not clear to me hot to accomplish setting an opacity value to a background color.

I am using to UI Properties to obtain the brush color and the opacity value.

Brush: hTFBullishTrendBackgroundColor

Opacity as an integer: hTFBullishBackgroundOpacity

if (Closes[1][0] > Closes[1][1])

{



Brush hTFBullishTrendBackgroundColorCopy = hTFBullishTrendBackgroundColor;

hTFBullishTrendBackgroundColorCopy.Opacity = hTFBullishBackgroundOpacity/100d;

hTFBullishTrendBackgroundColorCopy.Freeze();

BackBrush = hTFBullishTrendBackgroundColorCopy;

}

I don't want to use SolidColorBrush to define the brush and transparency value as I am getting this information from the user.


What I am missing? When I ran this code I get the following error:

 Error on calling 'OnBarUpdate' method on bar 95: Cannot set a property on object '#FF3E3D42' because it is in a read-only state.

[NinjaTrader_Jesse]

Hello GARZONJ,

You will need to use a SolidColorBrush to define opacity so that part is going to be required, that is needed if you are copying a color so you can access the Color property.

You also need to create a new brush that is not already created, you can't modify opacity on an existing brush. In what you provided I don't see that part.

SolidColorBrush existingBrush = (SolidColorBrush)UserInputBrushHere; //cast to solidcolor so you can access .Color
Brush newBackBrush = new SolidColorBrush(existingBrush.Color);  // make a brand new brush using the existing color infomration

The other post is really the bare minimum at what you would need to copy the existing brush information and make a new brush with an opacity. You can find more information about working with brushes here: https://ninjatrader.com/support/help...gcustombrushes

If you are taking user input the other post would provide a good structure for taking the color input. You could replace BackBrush in that sample with your user input brush, the null check should not be needed if you are setting a default.
I look forward to being of further assistance.