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copied!<p>I think you want a control that can contain other controls — like <code>TPanel</code> can do — and a control that can display the contents of the window underneath it — like <code>TImage</code> can do when its <code>Transparent</code> property is set. It appears you are under the mistaken impression that if you put one control on top of another, you'll get the behavior of both combined. <em>That's</em> what's wrong.</p> <p>First thing you should do is get rid of the <code>TImage</code> control. That's just making things more complicated than they need to be. When you need to draw a brush pattern on the panel, draw it directly onto the panel.</p> <p>Next, realize that the <code>ws_ex_Transparent</code> window style controls whether <em>siblings</em> of the window are painted first. That says nothing about whether the <em>parent</em> of the window gets repainted. If the parent of your panel has the <code>ws_ClipChildren</code> style set, then it will not paint itself underneath where your panel supposedly is. It looks like it would help you if the parent of your panel control had the <code>ws_ex_Composited</code> style set, but as a component writer, you don't get control over your controls' parents.</p> <p><code>TImage</code> is able to appear transparent because it is not a windowed control. It has no window handle, so the OS rules about painting and clipping don't apply to it. From Windows' point of view, <code>TImage</code> doesn't exist at all. What we in the Delphi world perceive as the <code>TImage</code> painting itself is really the parent window deferring to a separate subroutine to paint a certain region of the parent window. Because of that, the <code>TImage</code> painting code can simply not paint over some of the parent's area.</p> <p>If I were doing this, I'd ask myself whether the control with the brush pattern really needed to be a container control. Could I instead just use an ordinary <code>TImage</code> with a repeating brush pattern drawn on it? Other controls can still go on top of it, but they won't be considered children of the pattern control.</p>

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