From 5456d6fc31a43676f3e05cc6ecebde31d562ccfc Mon Sep 17 00:00:00 2001
From: blikblum <blikblum@lazarus-ide.org>
Date: Tue, 10 Aug 2010 16:52:59 +0000
Subject: [PATCH] wince: avoid sending LM_CHANGE message when clearing
 TRadioButton siblings and when setting TRadioButton checked property
 programatically. Send LM_CHANGE when TRadioButton is unchecked. Don't toggle
 TRadioButton state when it's already checked. Part of 0017139 and 0017104

git-svn-id: trunk@27051 -
---
 lcl/interfaces/wince/wincecallback.inc  | 64 +++++++++++++++----------
 lcl/interfaces/wince/wincewsstdctrls.pp |  3 +-
 2 files changed, 40 insertions(+), 27 deletions(-)

diff --git a/lcl/interfaces/wince/wincecallback.inc b/lcl/interfaces/wince/wincecallback.inc
index 348c6c6658..e6d2017ad5 100644
--- a/lcl/interfaces/wince/wincecallback.inc
+++ b/lcl/interfaces/wince/wincecallback.inc
@@ -544,15 +544,22 @@ Var
   var
     Parent: TWinControl;
     Sibling: TControl;
+    WinControl: TWinControlAccess absolute Sibling;
+    PreviousCheckState: LRESULT;
     i: Integer;
   begin
     Parent := RadioButton.Parent;
-    for i:= 0 to Parent.ControlCount - 1 do begin
+    for i:= 0 to Parent.ControlCount - 1 do
+    begin
       Sibling := Parent.Controls[i];
-      if (Sibling is TRadioButton) and (Sibling<>RadioButton) and
-         (TRadioButton(Sibling).HandleAllocated) then
-         Windows.SendMessageW(TRadioButton(Sibling).Handle, BM_SETCHECK,
-            Windows.WParam(BST_UNCHECKED), 0);
+      if (Sibling is TRadioButton) and (Sibling <> RadioButton) then
+      begin
+        // Pass previous state through LParam so the event handling can decide
+        // when to propagate LM_CHANGE (New State <> Previous State)
+        PreviousCheckState := Windows.SendMessage(WinControl.WindowHandle, BM_GETCHECK, 0, 0);
+        Windows.SendMessage(WinControl.WindowHandle, BM_SETCHECK,
+          Windows.WParam(BST_UNCHECKED), Windows.LParam(PreviousCheckState));
+      end;
     end;
   end;
 
@@ -1053,10 +1060,6 @@ begin
         end;
       end;
     end;
-    BM_SETCHECK:
-    begin
-      LMessage.Msg := LM_CHANGED;
-    end;
     WM_CAPTURECHANGED:
     begin
       LMessage.Msg := LM_CAPTURECHANGED;
@@ -1160,18 +1163,22 @@ begin
                   // in checkboxes (needed by dbcheckbox for null fields) we need
                   // to handle checkbox state ourselves, according to msdn state
                   // sequence goes from checked->cleared->grayed etc.
-                  Flags := SendMessageW(lWinControl.Handle, BM_GETCHECK, 0, 0);
-                  if (Flags=BST_CHECKED) then
-                    Flags := BST_UNCHECKED
-                  else
-                  if (Flags=BST_UNCHECKED) and
-                     TCustomCheckbox(lWinControl).AllowGrayed then
-                    Flags := BST_INDETERMINATE
-                  else
-                    Flags := BST_CHECKED;
-                  Windows.SendMessageW(lWinControl.Handle, BM_SETCHECK,
-                                                      Windows.WPARAM(flags), 0);
-
+                  Flags := SendMessage(lWinControl.Handle, BM_GETCHECK, 0, 0);
+                  //dont update the check state if is TRadioButton and is already checked
+                  if (Flags <> BST_CHECKED) or not (lWinControl is TRadioButton) then
+                  begin
+                    if (Flags=BST_CHECKED) then
+                      Flags := BST_UNCHECKED
+                    else
+                    if (Flags=BST_UNCHECKED) and
+                       TCustomCheckbox(lWinControl).AllowGrayed then
+                      Flags := BST_INDETERMINATE
+                    else
+                      Flags := BST_CHECKED;
+                    //pass a different values in WParam and WParam to force sending LM_CHANGE
+                    Windows.SendMessage(lWinControl.Handle, BM_SETCHECK,
+                      Windows.WPARAM(Flags), Windows.LPARAM(Flags + 1));
+                  end;
                   LMessage.Msg := LM_CLICKED;
                 end;
               BN_KILLFOCUS:
@@ -1847,9 +1854,6 @@ begin
       LMessage.Msg := LM_SETFOCUS;
       if (lWinControl <> nil) and (lWinControl.FCompStyle = csEdit) then
         Windows.SendMessage(Window, EM_SETSEL, 0, -1);
-      // RadioButton functionality
-      if (lWinControl <> nil) and (lWinControl is TRadioButton) then
-        Windows.SendMessage(Window, BM_SETCHECK, BST_CHECKED, 0);
     end;
     WM_SHOWWINDOW:
     begin
@@ -2083,8 +2087,16 @@ begin
     end;
     BM_SETCHECK:
     begin
-      if (WParam=BST_CHECKED) and (lWinControl is TRadioButton) then
-        ClearSiblingRadioButtons(TRadioButton(lWinControl));
+      //LParam holds previous state
+      //Propagate LM_CHANGED when state is changed
+      if LParam <> WParam then
+        LMessage.Msg := LM_CHANGED;
+      if lWinControl is TRadioButton then
+      begin
+        //Uncheck siblings
+        if WParam = BST_CHECKED then
+          ClearSiblingRadioButtons(TRadioButton(lWinControl));
+      end;
     end;
 
     //roozbeh : dont have these on ce!
diff --git a/lcl/interfaces/wince/wincewsstdctrls.pp b/lcl/interfaces/wince/wincewsstdctrls.pp
index eeadb56b27..ded7c5d2a1 100644
--- a/lcl/interfaces/wince/wincewsstdctrls.pp
+++ b/lcl/interfaces/wince/wincewsstdctrls.pp
@@ -1330,7 +1330,8 @@ begin
   else
     Flags := Windows.WParam(BST_INDETERMINATE);
   end;
-  Windows.SendMessage(ACustomCheckBox.Handle, BM_SETCHECK, Flags, 0);
+  //Pass the same state through lParam to avoid the OnChange event be fired
+  Windows.SendMessage(ACustomCheckBox.Handle, BM_SETCHECK, Flags, LPARAM(Flags));
 end;
 
 { TWinCEWSToggleBox }