TabWidget: Change automatic focus behavior on current page change

We now only set focus to a descendant if the TabWidget already contains the focus.

2 files changed, 35 insertions, 22 deletions

diff --git a/tabwidget.go b/tabwidget.go
index 55412fb5..64958836 100644
--- a/tabwidget.go
+++ b/tabwidget.go
@@ -295,7 +295,17 @@ func (tw *TabWidget) onSelChange() {
 		page.SetVisible(true)
 		tw.RequestLayout()
 		page.Invalidate()
-		tw.pages.At(tw.currentIndex).focusFirstCandidateDescendant()
+
+		var containsFocus bool
+		tw.forEachDescendantRaw(uintptr(win.GetFocus()), func(hwnd win.HWND, lParam uintptr) bool {
+			if hwnd == win.HWND(lParam) {
+				containsFocus = true
+			}
+			return !containsFocus
+		})
+		if containsFocus {
+			tw.pages.At(tw.currentIndex).focusFirstCandidateDescendant()
+		}
 	}
 
 	tw.Invalidate()
@@ -490,26 +500,6 @@ func tabWidgetTabWndProc(hwnd win.HWND, msg uint32, wParam, lParam uintptr) uint
 		}
 
 		return 0
-
-	case win.WM_LBUTTONDOWN:
-		x := win.GET_X_LPARAM(lParam)
-		y := win.GET_Y_LPARAM(lParam)
-
-		hti := win.TCHITTESTINFO{
-			Pt: win.POINT{x, y},
-		}
-
-		i := int(win.SendMessage(hwnd, win.TCM_HITTEST, 0, uintptr(unsafe.Pointer(&hti))))
-
-		if i == -1 {
-			break
-		}
-
-		ret := win.CallWindowProc(tw.tabOrigWndProcPtr, hwnd, msg, wParam, lParam)
-
-		tw.pages.At(i).focusFirstCandidateDescendant()
-
-		return ret
 	}
 
 	return win.CallWindowProc(tw.tabOrigWndProcPtr, hwnd, msg, wParam, lParam)
diff --git a/window.go b/window.go
index 4233bc4d..21fdd2ea 100644
--- a/window.go
+++ b/window.go
@@ -452,6 +452,7 @@ var (
 func init() {
 	AppendToWalkInit(func() {
 		forEachDescendantCallbackPtr = syscall.NewCallback(forEachDescendant)
+		forEachDescendantRawCallbackPtr = syscall.NewCallback(forEachDescendantRaw)
 		dialogBaseUnitsUTF16StringPtr = syscall.StringToUTF16Ptr("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz")
 	})
 }
@@ -1259,7 +1260,7 @@ func (wb *WindowBase) Form() Form {
 }
 
 func forEachDescendant(hwnd win.HWND, lParam uintptr) uintptr {
-	if window := windowFromHandle(hwnd); window != nil && forEachDescendantCallback(window.(Widget)) {
+	if window := windowFromHandle(hwnd); window == nil || forEachDescendantCallback(window.(Widget)) {
 		return 1
 	}
 
@@ -1280,6 +1281,28 @@ func (wb *WindowBase) ForEachDescendant(f func(widget Widget) bool) {
 	win.EnumChildWindows(wb.hWnd, forEachDescendantCallbackPtr, 0)
 }
 
+func forEachDescendantRaw(hwnd win.HWND, lParam uintptr) uintptr {
+	if forEachDescendantRawCallback(hwnd, lParam) {
+		return 1
+	}
+
+	return 0
+}
+
+var (
+	forEachDescendantRawCallbackPtr uintptr
+	forEachDescendantRawCallback    func(hwnd win.HWND, lParam uintptr) bool
+)
+
+func (wb *WindowBase) forEachDescendantRaw(lParam uintptr, f func(hwnd win.HWND, lParam uintptr) bool) {
+	forEachDescendantRawCallback = f
+	defer func() {
+		forEachDescendantRawCallback = nil
+	}()
+
+	win.EnumChildWindows(wb.hWnd, forEachDescendantRawCallbackPtr, lParam)
+}
+
 // Visible returns if the *WindowBase is visible.
 func (wb *WindowBase) Visible() bool {
 	return win.IsWindowVisible(wb.hWnd)