place a form with Opacity over a main form with datagridview winform

I have a form (named mainForm.cs) with a datagridview on it.

I must to show a picture (with opacity) over a datagrdiview. To achieve this, I made another form (frmPicture) with a picturebox, and apply the opacity property to the form. It also set the opacity = 100 when the mouse get inside the form (frmPicture) and opacity = 30 when the mouse leave the form. And we need to resize on click.

The problem is when I minimize the mainForm, the other form is still in their place.

I must to find the way like Visual Studios does when the methods appears in a list (after typing a开发者_如何转开发 dot) and pressing the Control key to change the opacity of a list.

I hope anybody can help me.

Thanks in advance.

Best regards.

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If you set the Main form as the owner of the form being overlayed, it will minimize with the Main form, i.e.

     OverlayForm form = new OverlayForm();
     form.Show(this);

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I would bet VS uses a ContextMenu or the new ContextMenuStrip, not another form....

Edit - deleted bad advice

HOWEVER, for the situation you're facing now, I would use the Form's Deactivate() event, and hide your other form in that event handler. This way it will hide when your form goes out of focus just like VS.