TableView: Display header tool tips for too narrow columns

2 files changed, 63 insertions, 12 deletions

diff --git a/tableview.go b/tableview.go
index b0593ef3..a570079d 100644
--- a/tableview.go
+++ b/tableview.go
@@ -246,6 +246,9 @@ func NewTableViewWithCfg(parent Container, cfg *TableViewCfg) (*TableView, error
 	win.SendMessage(tv.hwndFrozenLV, win.WM_CHANGEUISTATE, uintptr(win.MAKELONG(win.UIS_SET, win.UISF_HIDEFOCUS)), 0)
 	win.SendMessage(tv.hwndNormalLV, win.WM_CHANGEUISTATE, uintptr(win.MAKELONG(win.UIS_SET, win.UISF_HIDEFOCUS)), 0)
 
+	tv.group.toolTip.addTool(tv.hwndFrozenHdr, false)
+	tv.group.toolTip.addTool(tv.hwndNormalHdr, false)
+
 	tv.applyFont(parent.Font())
 
 	tv.style.dpi = tv.DPI()
@@ -343,11 +346,13 @@ func (tv *TableView) Dispose() {
 	}
 
 	if tv.hwndFrozenLV != 0 {
+		tv.group.toolTip.removeTool(tv.hwndFrozenHdr)
 		win.DestroyWindow(tv.hwndFrozenLV)
 		tv.hwndFrozenLV = 0
 	}
 
 	if tv.hwndNormalLV != 0 {
+		tv.group.toolTip.removeTool(tv.hwndNormalHdr)
 		win.DestroyWindow(tv.hwndNormalLV)
 		tv.hwndNormalLV = 0
 	}
@@ -2439,6 +2444,45 @@ func tableViewHdrWndProc(hwnd win.HWND, msg uint32, wp, lp uintptr) uintptr {
 		hdl.Pwpos.Cy = int32(tv.customHeaderHeight)
 
 		return result
+
+	case win.WM_MOUSEMOVE, win.WM_LBUTTONDOWN, win.WM_LBUTTONUP, win.WM_MBUTTONDOWN, win.WM_MBUTTONUP, win.WM_RBUTTONDOWN, win.WM_RBUTTONUP:
+		hti := win.HDHITTESTINFO{Pt: win.POINT{int32(win.GET_X_LPARAM(lp)), int32(win.GET_Y_LPARAM(lp))}}
+		win.SendMessage(hwnd, win.HDM_HITTEST, 0, uintptr(unsafe.Pointer(&hti)))
+		if hti.IItem == -1 {
+			tv.group.toolTip.setText(hwnd, "")
+			break
+		}
+
+		col := tv.fromLVColIdx(hwnd == tv.hwndFrozenHdr, hti.IItem)
+		text := tv.columns.At(col).TitleEffective()
+
+		var rc win.RECT
+		if 0 == win.SendMessage(hwnd, win.HDM_GETITEMRECT, uintptr(hti.IItem), uintptr(unsafe.Pointer(&rc))) {
+			tv.group.toolTip.setText(hwnd, "")
+			break
+		}
+
+		size := calculateTextSize(text, tv.Font(), tv.DPI(), 0, hwnd)
+		if size.Width <= rectangleFromRECT(rc).Width-int(win.SendMessage(hwnd, win.HDM_GETBITMAPMARGIN, 0, 0)) {
+			tv.group.toolTip.setText(hwnd, "")
+			break
+		}
+
+		if tv.group.toolTip.text(hwnd) == text {
+			break
+		}
+
+		tv.group.toolTip.setText(hwnd, text)
+
+		m := win.MSG{
+			HWnd:    hwnd,
+			Message: msg,
+			WParam:  wp,
+			LParam:  lp,
+			Pt:      hti.Pt,
+		}
+
+		tv.group.toolTip.SendMessage(win.TTM_RELAYEVENT, 0, uintptr(unsafe.Pointer(&m)))
 	}
 
 	return win.CallWindowProc(origWndProcPtr, hwnd, msg, wp, lp)
diff --git a/tooltip.go b/tooltip.go
index 5b6f9283..e16866cf 100644
--- a/tooltip.go
+++ b/tooltip.go
@@ -114,7 +114,7 @@ func (tt *ToolTip) track(tool Widget) error {
 		return nil
 	}
 
-	ti := tt.toolInfo(tool)
+	ti := tt.toolInfo(tool.Handle())
 	if ti == nil {
 		return newError("unknown tool")
 	}
@@ -146,7 +146,7 @@ func (tt *ToolTip) track(tool Widget) error {
 }
 
 func (tt *ToolTip) untrack(tool Widget) error {
-	ti := tt.toolInfo(tool)
+	ti := tt.toolInfo(tool.Handle())
 	if ti == nil {
 		return newError("unknown tool")
 	}
@@ -157,15 +157,14 @@ func (tt *ToolTip) untrack(tool Widget) error {
 }
 
 func (tt *ToolTip) AddTool(tool Widget) error {
-	return tt.addTool(tool, false)
+	return tt.addTool(tt.hwndForTool(tool), false)
 }
 
 func (tt *ToolTip) addTrackedTool(tool Widget) error {
-	return tt.addTool(tool, true)
+	return tt.addTool(tt.hwndForTool(tool), true)
 }
 
-func (tt *ToolTip) addTool(tool Widget, track bool) error {
-	hwnd := tt.hwndForTool(tool)
+func (tt *ToolTip) addTool(hwnd win.HWND, track bool) error {
 	if hwnd == 0 {
 		return nil
 	}
@@ -189,8 +188,10 @@ func (tt *ToolTip) addTool(tool Widget, track bool) error {
 }
 
 func (tt *ToolTip) RemoveTool(tool Widget) error {
-	hwnd := tt.hwndForTool(tool)
+	return tt.removeTool(tt.hwndForTool(tool))
+}
 
+func (tt *ToolTip) removeTool(hwnd win.HWND) error {
 	var ti win.TOOLINFO
 	ti.CbSize = uint32(unsafe.Sizeof(ti))
 	ti.Hwnd = hwnd
@@ -202,7 +203,11 @@ func (tt *ToolTip) RemoveTool(tool Widget) error {
 }
 
 func (tt *ToolTip) Text(tool Widget) string {
-	ti := tt.toolInfo(tool)
+	return tt.text(tt.hwndForTool(tool))
+}
+
+func (tt *ToolTip) text(hwnd win.HWND) string {
+	ti := tt.toolInfo(hwnd)
 	if ti == nil {
 		return ""
 	}
@@ -211,7 +216,11 @@ func (tt *ToolTip) Text(tool Widget) string {
 }
 
 func (tt *ToolTip) SetText(tool Widget, text string) error {
-	ti := tt.toolInfo(tool)
+	return tt.setText(tt.hwndForTool(tool), text)
+}
+
+func (tt *ToolTip) setText(hwnd win.HWND, text string) error {
+	ti := tt.toolInfo(hwnd)
 	if ti == nil {
 		return newError("unknown tool")
 	}
@@ -236,12 +245,10 @@ func (tt *ToolTip) SetText(tool Widget, text string) error {
 	return nil
 }
 
-func (tt *ToolTip) toolInfo(tool Widget) *win.TOOLINFO {
+func (tt *ToolTip) toolInfo(hwnd win.HWND) *win.TOOLINFO {
 	var ti win.TOOLINFO
 	var buf [maxToolTipTextLen]uint16
 
-	hwnd := tt.hwndForTool(tool)
-
 	ti.CbSize = uint32(unsafe.Sizeof(ti))
 	ti.Hwnd = hwnd
 	ti.UId = uintptr(hwnd)