Fit Table Tooltip in a single monitor for Win32

This commit contributes to the fitting of the table tooltip inside a
single monitor if it spans over multiple monitor to avoid any
infinite loop because of rescaling triggered by any DPI_CHANGED events.

contributes to
#62 and
#128

Author: amartya4256

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/CoordinateSystemMapper.java

@@ -35,6 +35,8 @@ interface CoordinateSystemMapper {
 
 	Rectangle translateToDisplayCoordinates(Rectangle rect, int zoom);
 
+	Rectangle getContainingMonitorBoundsInPixels(Point point);
+
 	void setCursorLocation(int x, int y);
 
 	Point getCursorLocation();

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Display.java

@@ -1724,6 +1724,25 @@ public Point getCursorLocation () {
 	return coordinateSystemMapper.getCursorLocation();
 }
 
+Rectangle fitRectangleBoundsIntoMonitor(RECT rect) {
+	Rectangle monitorBounds = coordinateSystemMapper.getContainingMonitorBoundsInPixels(getCursorLocation());
+	int rectWidth = rect.right - rect.left;
+	int rectHeight = rect.bottom - rect.top;
+	if (rect.left < monitorBounds.x) {
+		rect.left = monitorBounds.x;
+	}
+	int monitorBoundsRightEnd = monitorBounds.x + monitorBounds.width;
+	if (rect.right > monitorBoundsRightEnd) {
+		if (rectWidth <= monitorBounds.width) {
+			rect.left = monitorBoundsRightEnd - rectWidth;
+		} else {
+			rect.left = monitorBounds.x;
+		}
+		rectWidth = monitorBoundsRightEnd - rect.left;
+	}
+	return new Rectangle(rect.left, rect.top, rectWidth, rectHeight);
+}
+
 Point getCursorLocationInPixels () {
 	POINT pt = new POINT ();
 	OS.GetCursorPos (pt);

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/MultiZoomCoordinateSystemMapper.java

@@ -271,4 +271,12 @@ private int getApplicableMonitorZoom(Monitor monitor) {
 		return DPIUtil.getZoomForAutoscaleProperty(monitor.zoom);
 	}
 
+	@Override
+	public Rectangle getContainingMonitorBoundsInPixels(Point point) {
+		Monitor monitor = point instanceof MonitorAwarePoint monitorAwarePoint
+				? monitorAwarePoint.getMonitor()
+				:getContainingMonitorForPoints(point.x, point.y);
+		return getMonitorClientAreaInPixels(monitor);
+	}
+
 }

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/SingleZoomCoordinateSystemMapper.java

@@ -105,4 +105,17 @@ public Point getCursorLocation() {
 	public void setCursorLocation(int x, int y) {
 		display.setCursorLocationInPixels(DPIUtil.autoScaleUp(x), DPIUtil.autoScaleUp(y));
 	}
+
+	@Override
+	public Rectangle getContainingMonitorBoundsInPixels(Point point) {
+		int zoom = DPIUtil.getDeviceZoom();
+		point = DPIUtil.scaleUp(point, zoom);
+		for (Monitor monitor : display.getMonitors()) {
+			Rectangle monitorBounds = DPIUtil.scaleUp(monitor.getBounds(), zoom);
+			if (monitorBounds.contains(point)) {
+				return monitorBounds;
+			}
+		}
+		return null;
+	}
 }

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Table.java

@@ -7158,82 +7158,87 @@ LRESULT wmNotifyToolTip (NMHDR hdr, long wParam, long lParam) {
 		case OS.TTN_SHOW: {
 			LRESULT result = super.wmNotify (hdr, wParam, lParam);
 			if (result != null) return result;
-			if (hdr.code != OS.TTN_SHOW) tipRequested = true;
-			long code = callWindowProc (handle, OS.WM_NOTIFY, wParam, lParam);
-			if (hdr.code != OS.TTN_SHOW) tipRequested = false;
 			if (toolTipText != null) break;
-			if (isCustomToolTip ()) {
-				LVHITTESTINFO pinfo = new LVHITTESTINFO ();
-				int pos = OS.GetMessagePos ();
-				POINT pt = new POINT();
-				OS.POINTSTOPOINT (pt, pos);
-				OS.ScreenToClient (handle, pt);
-				pinfo.x = pt.x;
-				pinfo.y = pt.y;
-				/*
-				*  Bug in Windows.  When LVM_SUBITEMHITTEST is used to hittest
-				*  a point that is above the table, instead of returning -1 to
-				*  indicate that the hittest failed, a negative index is returned.
-				*  The fix is to consider any value that is negative a failure.
-				*/
-				if (OS.SendMessage (handle, OS.LVM_SUBITEMHITTEST, 0, pinfo) >= 0) {
-					TableItem item = _getItem (pinfo.iItem);
-					long hDC = OS.GetDC (handle);
-					long oldFont = 0, newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
-					if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
-					long hFont = item.fontHandle (pinfo.iSubItem);
-					if (hFont != -1) hFont = OS.SelectObject (hDC, hFont);
-					Event event = sendMeasureItemEvent (item, pinfo.iItem, pinfo.iSubItem, hDC);
-					if (!isDisposed () && !item.isDisposed ()) {
-						RECT itemRect = new RECT ();
-						Rectangle boundsInPixels = DPIUtil.scaleUp(event.getBounds(), getZoom());
-						OS.SetRect (itemRect, boundsInPixels.x, boundsInPixels.y, boundsInPixels.x + boundsInPixels.width, boundsInPixels.y + boundsInPixels.height);
-						if (hdr.code == OS.TTN_SHOW) {
-							RECT toolRect = toolTipRect (itemRect);
-							OS.MapWindowPoints (handle, 0, toolRect, 2);
-							long hwndToolTip = OS.SendMessage (handle, OS.LVM_GETTOOLTIPS, 0, 0);
-							int flags = OS.SWP_NOACTIVATE | OS.SWP_NOZORDER;
-							int width = toolRect.right - toolRect.left, height = toolRect.bottom - toolRect.top;
-							OS.SetWindowPos (hwndToolTip, 0, toolRect.left , toolRect.top, width, height, flags);
-						} else {
-							NMTTDISPINFO lpnmtdi = new NMTTDISPINFO ();
-							OS.MoveMemory (lpnmtdi, lParam, NMTTDISPINFO.sizeof);
-							if (lpnmtdi.lpszText != 0) {
-								OS.MoveMemory (lpnmtdi.lpszText, new char [1], 2);
-								OS.MoveMemory (lParam, lpnmtdi, NMTTDISPINFO.sizeof);
-							}
-							RECT cellRect = item.getBounds (pinfo.iItem, pinfo.iSubItem, true, true, true, true, hDC);
-							RECT clientRect = new RECT ();
-							OS.GetClientRect (handle, clientRect);
-							if (itemRect.right > cellRect.right || itemRect.right > clientRect.right) {
-								//TEMPORARY CODE
-								String string = " ";
+			if (isCustomToolTip () || hdr.code == OS.TTN_SHOW) {
+				result = positionTooltip(hdr, lParam);
+			}
+			return result;
+		}
+	}
+	return null;
+}
+
+private LRESULT positionTooltip(NMHDR hdr, long lParam) {
+	LRESULT result = null;
+	LVHITTESTINFO pinfo = new LVHITTESTINFO ();
+	int pos = OS.GetMessagePos ();
+	POINT pt = new POINT();
+	OS.POINTSTOPOINT (pt, pos);
+	OS.ScreenToClient (handle, pt);
+	pinfo.x = pt.x;
+	pinfo.y = pt.y;
+	/*
+	*  Bug in Windows.  When LVM_SUBITEMHITTEST is used to hittest
+	*  a point that is above the table, instead of returning -1 to
+	*  indicate that the hittest failed, a negative index is returned.
+	*  The fix is to consider any value that is negative a failure.
+	*/
+	if (OS.SendMessage (handle, OS.LVM_SUBITEMHITTEST, 0, pinfo) >= 0) {
+		TableItem item = _getItem (pinfo.iItem);
+		long hDC = OS.GetDC (handle);
+		long oldFont = 0, newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
+		if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
+		long hFont = item.fontHandle (pinfo.iSubItem);
+		if (hFont != -1) hFont = OS.SelectObject (hDC, hFont);
+		Event event = sendMeasureItemEvent (item, pinfo.iItem, pinfo.iSubItem, hDC);
+		if (!isDisposed () && !item.isDisposed ()) {
+			RECT itemRect = new RECT ();
+			Rectangle boundsInPixels = DPIUtil.scaleUp(event.getBounds(), getZoom());
+			OS.SetRect (itemRect, boundsInPixels.x, boundsInPixels.y, boundsInPixels.x + boundsInPixels.width, boundsInPixels.y + boundsInPixels.height);
+			if (hdr.code == OS.TTN_SHOW) {
+				RECT toolRect = isCustomToolTip() ? toolTipRect (itemRect) : itemRect;
+				OS.MapWindowPoints (handle, 0, toolRect, 2);
+				long hwndToolTip = OS.SendMessage (handle, OS.LVM_GETTOOLTIPS, 0, 0);
+				int flags = OS.SWP_NOACTIVATE | OS.SWP_NOZORDER;
+				Rectangle adjustedTooltipBounds = getDisplay().fitRectangleBoundsIntoMonitor(toolRect);
+				OS.SetWindowPos(hwndToolTip, 0, adjustedTooltipBounds.x, adjustedTooltipBounds.y,
+						adjustedTooltipBounds.width, adjustedTooltipBounds.height, flags);
+				result = LRESULT.ONE;
+			} else {
+				NMTTDISPINFO lpnmtdi = new NMTTDISPINFO ();
+				OS.MoveMemory (lpnmtdi, lParam, NMTTDISPINFO.sizeof);
+				if (lpnmtdi.lpszText != 0) {
+					OS.MoveMemory (lpnmtdi.lpszText, new char [1], 2);
+					OS.MoveMemory (lParam, lpnmtdi, NMTTDISPINFO.sizeof);
+				}
+				RECT cellRect = item.getBounds (pinfo.iItem, pinfo.iSubItem, true, true, true, true, hDC);
+				RECT clientRect = new RECT ();
+				OS.GetClientRect (handle, clientRect);
+				if (itemRect.right > cellRect.right || itemRect.right > clientRect.right) {
+					//TEMPORARY CODE
+					String string = " ";
 //								String string = null;
 //								if (pinfo.iSubItem == 0) {
 //									string = item.text;
 //								} else {
 //									String [] strings  = item.strings;
 //									if (strings != null) string = strings [pinfo.iSubItem];
 //								}
-								if (string != null) {
-									Shell shell = getShell ();
-									char [] chars = new char [string.length () + 1];
-									string.getChars (0, string.length (), chars, 0);
-									shell.setToolTipText (lpnmtdi, chars);
-									OS.MoveMemory (lParam, lpnmtdi, NMTTDISPINFO.sizeof);
-								}
-							}
-						}
+					if (string != null) {
+						Shell shell = getShell ();
+						char [] chars = new char [string.length () + 1];
+						string.getChars (0, string.length (), chars, 0);
+						shell.setToolTipText (lpnmtdi, chars);
+						OS.MoveMemory (lParam, lpnmtdi, NMTTDISPINFO.sizeof);
 					}
-					if (hFont != -1) hFont = OS.SelectObject (hDC, hFont);
-					if (newFont != 0) OS.SelectObject (hDC, oldFont);
-					OS.ReleaseDC (handle, hDC);
 				}
 			}
-			return new LRESULT (code);
 		}
+		if (hFont != -1) hFont = OS.SelectObject (hDC, hFont);
+		if (newFont != 0) OS.SelectObject (hDC, oldFont);
+		OS.ReleaseDC (handle, hDC);
 	}
-	return null;
+	return result;
 }
 
 LRESULT wmNotifyToolTip (NMTTCUSTOMDRAW nmcd, long lParam) {

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Tree.java

@@ -8175,15 +8175,10 @@ private LRESULT positionTooltip(NMHDR hdr, long wParam, long lParam, boolean man
 		// triggers additional display messages to SWT, creating an infinite loop
 		// of positioning and re-scaling events.
 		// Refer: https://github.com/eclipse-platform/eclipse.platform.swt/issues/557
-		Point cursorLocation = display.getCursorLocation();
-		Rectangle monitorBounds = cursorLocation instanceof MonitorAwarePoint monitorAwarePoint
-				? getContainingMonitorBoundsInMultiZoomCoordinateSystem(monitorAwarePoint)
-				: getContainingMonitorBoundsInSingleZoomCoordinateSystem(cursorLocation);
-		if (monitorBounds != null) {
-			Rectangle adjustedTooltipBounds = fitTooltipBoundsIntoMonitor(toolRect, monitorBounds);
-			OS.SetWindowPos (hdr.hwndFrom, 0, adjustedTooltipBounds.x, adjustedTooltipBounds.y, adjustedTooltipBounds.width, adjustedTooltipBounds.height, flags);
-			result = LRESULT.ONE;
-		}
+
+		Rectangle adjustedTooltipBounds = getDisplay().fitRectangleBoundsIntoMonitor(toolRect);
+		OS.SetWindowPos (hdr.hwndFrom, 0, adjustedTooltipBounds.x, adjustedTooltipBounds.y, adjustedTooltipBounds.width, adjustedTooltipBounds.height, flags);
+		result = LRESULT.ONE;
 	} else if (!managedTooltip) {
 		// If managedTooltip is false and the cursor is not over the valid part of the
 		// target cell, Windows may still try to display the default tooltip. Since we
@@ -8196,39 +8191,6 @@ private LRESULT positionTooltip(NMHDR hdr, long wParam, long lParam, boolean man
 	return result;
 }
 
-/**
- * Adjust the tool tip to fit in a single monitor either by shifting its position or by adjusting it's width.
- */
-private Rectangle fitTooltipBoundsIntoMonitor(RECT tooltipBounds, Rectangle monitorBounds) {
-	int tooltipWidth = tooltipBounds.right - tooltipBounds.left;
-	int tooltipHeight = tooltipBounds.bottom - tooltipBounds.top;
-	if (tooltipBounds.left < monitorBounds.x) {
-		tooltipBounds.left = monitorBounds.x;
-	}
-	int monitorBoundsRightEnd = monitorBounds.x + monitorBounds.width;
-	if (tooltipBounds.right > monitorBoundsRightEnd) {
-		if (tooltipWidth <= monitorBounds.width) {
-			tooltipBounds.left = monitorBoundsRightEnd - tooltipWidth;
-		} else {
-			tooltipBounds.left = monitorBounds.x;
-		}
-		tooltipWidth = monitorBoundsRightEnd - tooltipBounds.left;
-	}
-	return new Rectangle(tooltipBounds.left, tooltipBounds.top, tooltipWidth, tooltipHeight);
-}
-
-private Rectangle getContainingMonitorBoundsInSingleZoomCoordinateSystem(Point point) {
-	int zoom = getZoom();
-	point = DPIUtil.scaleUp(point, zoom);
-	for (Monitor monitor : display.getMonitors()) {
-		Rectangle monitorBounds = DPIUtil.scaleUp(monitor.getBounds(), zoom);
-		if (monitorBounds.contains(point)) {
-			return monitorBounds;
-		}
-	}
-	return null;
-}
-
 private Rectangle getContainingMonitorBoundsInMultiZoomCoordinateSystem(MonitorAwarePoint point) {
 	Monitor monitor = point.getMonitor();
 	return new Rectangle(monitor.x, monitor.y, DPIUtil.scaleUp(monitor.width, monitor.zoom),