New Post: Horizontal Scroll Bar Issue

I have the horizontal scroll bar working OK and when the end user is typing it functions as expected however when setting the text of the document programmatically the scroll bar does not show until the container is clicked, the container is at the top of the zorder and as its just had its text drawn then its redrawn so how do I make the scroll bar show without the document being clicked?

Using Windows so its the winapi or a Scintilla function.