twm's blog

A few weeks ago I added the option to set the alignment and anchors properties for controls that support them to the GExperts Rename Component expert. After having used it for a while I found that the navigation using arrow keys left something to desire. It just wasn’t intuitive, e.g.: Pressing the down arrow key while the “Top” button had the focus moved the focus to the “Left” button. Pressing down again moved it to the “Client” button and again to the “Right” button.

The intuitive way would be that the up arrow key moves the focus to the control above the current one, the down arrow key move the focus to the control below the current one etc., like this:

So, how do you get the dialog to behave like this?

My first try was to write OnKeyDown handlers for the buttons, but that didn’t work, the handlers were never called. The second try was an OnKeyDown handler for the form and setting its KeyPreview property to true. Again, this didn’t work, the handler was never called. WTF?

Some googling turned up this question on StackOverflow and an answer that worked for me: Adding a DialogKey message handler to the form. (Thanks Sertak Kyuz”! I always appreciate it when somebody supports my lazyiness.). So I added the following code to GX_CompRename:

procedure TfmCompRename.DialogKey(var Msg: TWMKey);
begin
  // make the selection of alignment and anchors via arrow keys more intuitive
  case Msg.CharCode of
    VK_DOWN: begin
        if ActiveControl = b_AlignTop then
          b_AlignClient.SetFocus
        else if (ActiveControl = b_AlignClient) or (ActiveControl = b_AlignLeft) or (ActiveControl = b_AlignRight) then
          b_AlignBottom.SetFocus
        else if (ActiveControl = b_AnchorTop) or (ActiveControl = b_AnchorLeft) or (ActiveControl = b_AnchorRight) then
          b_AnchorBottom.SetFocus
        else
          inherited;
      end;
    VK_UP: begin
        if ActiveControl = b_AlignBottom then
          b_AlignClient.SetFocus
        else if (ActiveControl = b_AlignClient) or (ActiveControl = b_AlignLeft) or (ActiveControl = b_AlignRight) then
          b_AlignTop.SetFocus
        else if (ActiveControl = b_AlignNone) or (ActiveControl = b_AlignCustom)then
          b_AlignBottom.SetFocus
        else if (ActiveControl = b_AnchorBottom) or (ActiveControl = b_AnchorLeft) or (ActiveControl = b_AnchorRight) then
          b_AnchorTop.SetFocus
        else
          inherited;
      end;
    VK_RIGHT: begin
        if ActiveControl = b_AlignLeft then
          b_AlignClient.SetFocus
        else if ActiveControl = b_AlignClient then
          b_AlignRight.SetFocus
        else if (ActiveControl = b_AnchorTop) or (ActiveControl = b_AnchorBottom) or (ActiveControl = b_AnchorLeft) then
          b_AnchorRight.SetFocus
        else
          inherited;
      end;
    VK_LEFT: begin
        if ActiveControl = b_AlignRight then
          b_AlignClient.SetFocus
        else if ActiveControl = b_AlignClient then
          b_AlignLeft.SetFocus
        else if (ActiveControl = b_AnchorTop) or (ActiveControl = b_AnchorBottom) or (ActiveControl = b_AnchorRight) then
          b_AnchorLeft.SetFocus
        else
          inherited;
      end;
  else
    inherited;
  end;
end;

Now it works as shown in the picture.

It’s a small improvement, but one that makes me a bit more efficient. It took me about 2 hours to implement and test properly. So, according to XKCD it’s time well spent: I definitely use it more that 5 times a day, so spending 2 hours to save one second is fine. It saves those two hours across five years. And since I am not the only one using GExperts I hope I have saved a lot more than those two hours.

Speaking about saving time: Did you know that you can configure the Rename Components expert to automatically pop up for new controls when you drop them on a form?

You might have become used to it, but probably every Delphi developer has at one time wondered why the Messages window is still visible (and takes up valuable screen real estate) even if it is empty. And even worse, if you close it manually, it automatically comes back when you compile your project.

I too, had become used to it, but got reminded of this nuisance by a recent post from Graeme Geldenhuys on Google+:

How to auto close Message View window on successful compilation.
This was asked for in Delphi 7, but it seems with Delphi XE3 (what I’m using) it’s still not possible. Anybody know of a 3rd party add-in or hidden Delphi setting that will close the Message View after a successful compilation?

If I save my “desktop environment” while the Message View window is closed, then compile it doesn’t display the Message View – if no errors occurred. If a error occurs, then the Message View automatically appears. After I fixed the compilation error and recompile, the Message View stays there and doesn’t close. At this point I want it to close automatically. It is so damn annoying. I need all the screen (editor) space I can get, and the always visible Message View is taking up vital space.

Any known solution for this? Once again, Lazarus IDE does this perfectly.

As far as I know, there is no solution, neither in the Delphi IDE itself nor in any plugin I am aware of. (Update: There actually is one) Until today that is: I have just committed a change to the GExperts repository with the following description:

new IDE enhancement: Automatically close message window (if no errors, warnings or hints)

It is, like most IDE enhancements in GExperts, a hack. It works by hooking the Progress window and when it closes, checks whether there were any hints, warnings or errors. If there are none, it starts a timer that will wait for 1000 ms and then search and close the Messages window.

It works for me, your mileage may vary, of course. If you want to test it, for now you have to compile your own GExperts DLL. Don’t forget to actually enable that option on the IDE page of the configuration dialog!