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c#.netimagewinformstoolstripbutton

c# & winforms - unable to set Image of ToolStripButton

This seems like a fairly basic thing to do, but for some reason it just fails silently:

    /// <summary>
    /// Sets the button to show it's busy image
    /// </summary>
    public void SetBusy()
    {
        if (Control is Button)
        { ((Button)Control).Image = BusyImage; }
        else if (Control is ToolStripButton)
        { ((ToolStripButton)Control).Image = BusyImage; }
    }

BusyImage is set using BusyImage = Properties.Resources.Busy;

If I debug this, I can see that the image appears to be setting correctly (if I hover over the Image member when at a breakpoint I can see it change), but it doesn't actually change the image when you look at the button.

I have noticed that this works when all the above code is hosted in the same Project file as the UI, but when it's shipped out to a different project (but within the same Solution), it fails silently.

Any ideas where I'm going wrong?

Thanks

EDIT 1: Even trying to set the Image to a file from the Resources of the same project as the ToolStripButton doesn't work (still fails silently).

Interestingly, it works absolutely fine when using a normal Button, regardless of which project the images are in.

Why the difference in behaviour between Button and ToolStripButton?

EDIT 2: It appears that moving the code that sets the image into the same project as the ToolStripButton works. However, I would like to keep it in a separate project if at all possible...

Solution

  • Finally figured this out. To cut a long story short, I had some ToolStripButtons hidden somewhere in my form, only visible in the combobox in the designer's properties window (even when you select it from there, you can't see it on the form anywhere). I was passing the name of one of these to the ImageButton instead of the correct one (which had a default name like toolStripButton3)...

    I'd love to know how it happened, I suspect user error on my part...but then again I find it strange that VS will allow a ToolStripButton to exist when it doesn't appear on any ToolStrip on the form.

    Either way, my code seems to work quite happily now. The reason it appeared to work when run from the same project was that I was using a different button to test the theory.

    Lots of process of elimination got it down to just two buttons that weren't playing ball; on a hunch I decided to compare the properties of the working and non-working buttons, whereupon I discovered the issue...