From f08de69e4e4ff4d565fe3dfdf3ea239c62dfc8a5 Mon Sep 17 00:00:00 2001
From: zoran-vucenovic <zoran-vucenovic@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Sun, 10 Mar 2013 16:02:31 +0000
Subject: [PATCH] When TMonitor.WorkareaRect is not implemented, use
 TMonitor.BoundsRect

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@2697 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 components/ZVDateTimeCtrls/trunk/zvdatetimepicker.pas | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/components/ZVDateTimeCtrls/trunk/zvdatetimepicker.pas b/components/ZVDateTimeCtrls/trunk/zvdatetimepicker.pas
index 236800118..1fcebccaa 100644
--- a/components/ZVDateTimeCtrls/trunk/zvdatetimepicker.pas
+++ b/components/ZVDateTimeCtrls/trunk/zvdatetimepicker.pas
@@ -550,6 +550,7 @@ end;
 
 procedure TDTCalendarForm.AdjustCalendarFormScreenPosition;
 var
+  M: TMonitor;
   R: TRect;
   P: TPoint;
   H, W: Integer;
@@ -558,8 +559,14 @@ begin
   W := Width;
 
   P := DTPicker.ControlToScreen(Point(0, DTPicker.Height));
+  M := Screen.MonitorFromWindow(DTPicker.Handle);
 
-  R := Screen.MonitorFromWindow(DTPicker.Handle).WorkareaRect;
+  R := M.WorkareaRect;
+  // WorkareaRect sometimes is not implemented (gtk2?). Depends on widgetset
+  // and window manager or something like that. Then it returns (0,0,0,0) and
+  // the best we can do is use BoundsRect instead:
+  if (R.Right <= R.Left) or (R.Bottom <= R.Top) then
+    R := M.BoundsRect;
 
   if P.y > R.Bottom - H then
     P.y := P.y - H - DTPicker.Height;