Bug 564795 - [GTK4] Adapt to GtkContainer removal -

gtk_container_get_children

Change-Id: I5d0b2a3a515e1e8b480533492cab686ebfb6895e
Signed-off-by: Paul D'Pong <sdamrong@redhat.com>

15 files changed, 546 insertions, 269 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT Accessibility/gtk/org/eclipse/swt/accessibility/Accessible.java b/bundles/org.eclipse.swt/Eclipse SWT Accessibility/gtk/org/eclipse/swt/accessibility/Accessible.java
index 4188173386..a838f56fee 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT Accessibility/gtk/org/eclipse/swt/accessibility/Accessible.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT Accessibility/gtk/org/eclipse/swt/accessibility/Accessible.java
@@ -493,21 +493,32 @@ public class Accessible {
 
 	long getControlHandle () {
 		long result = control.handle;
+
 		if (control instanceof Label) {
-			long list = GTK.gtk_container_get_children (result);
-			if (list != 0) {
-				long temp = list;
-				while (temp != 0) {
-					long widget = OS.g_list_data( temp);
-					if (GTK.gtk_widget_get_visible (widget)) {
-						result = widget;
+			if (GTK.GTK4) {
+				for (long child = GTK.gtk_widget_get_first_child(result); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+					if (GTK.gtk_widget_get_visible(child)) {
+						result = child;
 						break;
 					}
-					temp = OS.g_list_next (temp);
 				}
-				OS.g_list_free (list);
+			} else {
+				long list = GTK.gtk_container_get_children (result);
+				if (list != 0) {
+					long temp = list;
+					while (temp != 0) {
+						long widget = OS.g_list_data( temp);
+						if (GTK.gtk_widget_get_visible (widget)) {
+							result = widget;
+							break;
+						}
+						temp = OS.g_list_next (temp);
+					}
+					OS.g_list_free (list);
+				}
 			}
 		}
+
 		return result;
 	}
 
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
index 1b54833b89..399ce37b4a 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
@@ -12015,7 +12015,15 @@ JNIEXPORT jlong JNICALL GTK_NATIVE(gtk_1widget_1get_1first_1child)
 {
 	jlong rc = 0;
 	GTK_NATIVE_ENTER(env, that, gtk_1widget_1get_1first_1child_FUNC);
+/*
 	rc = (jlong)gtk_widget_get_first_child((GtkWidget *)arg0);
+*/
+	{
+		GTK_LOAD_FUNCTION(fp, gtk_widget_get_first_child)
+		if (fp) {
+			rc = (jlong)((jlong (CALLING_CONVENTION*)(GtkWidget *))fp)((GtkWidget *)arg0);
+		}
+	}
 	GTK_NATIVE_EXIT(env, that, gtk_1widget_1get_1first_1child_FUNC);
 	return rc;
 }
@@ -12033,6 +12041,26 @@ JNIEXPORT jboolean JNICALL GTK_NATIVE(gtk_1widget_1get_1has_1window)
 }
 #endif
 
+#ifndef NO_gtk_1widget_1get_1last_1child
+JNIEXPORT jlong JNICALL GTK_NATIVE(gtk_1widget_1get_1last_1child)
+	(JNIEnv *env, jclass that, jlong arg0)
+{
+	jlong rc = 0;
+	GTK_NATIVE_ENTER(env, that, gtk_1widget_1get_1last_1child_FUNC);
+/*
+	rc = (jlong)gtk_widget_get_last_child((GtkWidget *)arg0);
+*/
+	{
+		GTK_LOAD_FUNCTION(fp, gtk_widget_get_last_child)
+		if (fp) {
+			rc = (jlong)((jlong (CALLING_CONVENTION*)(GtkWidget *))fp)((GtkWidget *)arg0);
+		}
+	}
+	GTK_NATIVE_EXIT(env, that, gtk_1widget_1get_1last_1child_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_gtk_1widget_1get_1mapped
 JNIEXPORT jboolean JNICALL GTK_NATIVE(gtk_1widget_1get_1mapped)
 	(JNIEnv *env, jclass that, jlong arg0)
@@ -12163,7 +12191,15 @@ JNIEXPORT jlong JNICALL GTK_NATIVE(gtk_1widget_1get_1next_1sibling)
 {
 	jlong rc = 0;
 	GTK_NATIVE_ENTER(env, that, gtk_1widget_1get_1next_1sibling_FUNC);
+/*
 	rc = (jlong)gtk_widget_get_next_sibling((GtkWidget *)arg0);
+*/
+	{
+		GTK_LOAD_FUNCTION(fp, gtk_widget_get_next_sibling)
+		if (fp) {
+			rc = (jlong)((jlong (CALLING_CONVENTION*)(GtkWidget *))fp)((GtkWidget *)arg0);
+		}
+	}
 	GTK_NATIVE_EXIT(env, that, gtk_1widget_1get_1next_1sibling_FUNC);
 	return rc;
 }
@@ -12345,6 +12381,26 @@ fail:
 }
 #endif
 
+#ifndef NO_gtk_1widget_1get_1prev_1sibling
+JNIEXPORT jlong JNICALL GTK_NATIVE(gtk_1widget_1get_1prev_1sibling)
+	(JNIEnv *env, jclass that, jlong arg0)
+{
+	jlong rc = 0;
+	GTK_NATIVE_ENTER(env, that, gtk_1widget_1get_1prev_1sibling_FUNC);
+/*
+	rc = (jlong)gtk_widget_get_prev_sibling((GtkWidget *)arg0);
+*/
+	{
+		GTK_LOAD_FUNCTION(fp, gtk_widget_get_prev_sibling)
+		if (fp) {
+			rc = (jlong)((jlong (CALLING_CONVENTION*)(GtkWidget *))fp)((GtkWidget *)arg0);
+		}
+	}
+	GTK_NATIVE_EXIT(env, that, gtk_1widget_1get_1prev_1sibling_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_gtk_1widget_1get_1realized
 JNIEXPORT jboolean JNICALL GTK_NATIVE(gtk_1widget_1get_1realized)
 	(JNIEnv *env, jclass that, jlong arg0)
@@ -13169,6 +13225,24 @@ fail:
 }
 #endif
 
+#ifndef NO_gtk_1widget_1unparent
+JNIEXPORT void JNICALL GTK_NATIVE(gtk_1widget_1unparent)
+	(JNIEnv *env, jclass that, jlong arg0)
+{
+	GTK_NATIVE_ENTER(env, that, gtk_1widget_1unparent_FUNC);
+/*
+	gtk_widget_unparent((GtkWidget *)arg0);
+*/
+	{
+		GTK_LOAD_FUNCTION(fp, gtk_widget_unparent)
+		if (fp) {
+			((void (CALLING_CONVENTION*)(GtkWidget *))fp)((GtkWidget *)arg0);
+		}
+	}
+	GTK_NATIVE_EXIT(env, that, gtk_1widget_1unparent_FUNC);
+}
+#endif
+
 #ifndef NO_gtk_1window_1activate_1default
 JNIEXPORT jboolean JNICALL GTK_NATIVE(gtk_1window_1activate_1default)
 	(JNIEnv *env, jclass that, jlong arg0)
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.h b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.h
index fd7b43b694..4513ebf592 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.h
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.h
@@ -550,8 +550,6 @@
 #define NO_gdk_1device_1warp__JII
 #define NO_gtk_1widget_1measure
 #define NO_gtk_1style_1context_1add_1provider_1for_1display
-#define NO_gtk_1widget_1get_1first_1child
-#define NO_gtk_1widget_1get_1next_1sibling
 #define NO_gtk_1css_1provider_1load_1from_1data__I_3BI
 #define NO_gtk_1css_1provider_1load_1from_1data__J_3BJ
 #define NO_gdk_1display_1is_1composited
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
index 8b2a31fc41..68b71bf2c9 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
@@ -951,6 +951,7 @@ char * GTK_nativeFunctionNames[] = {
 	"gtk_1widget_1get_1events",
 	"gtk_1widget_1get_1first_1child",
 	"gtk_1widget_1get_1has_1window",
+	"gtk_1widget_1get_1last_1child",
 	"gtk_1widget_1get_1mapped",
 	"gtk_1widget_1get_1margin_1bottom",
 	"gtk_1widget_1get_1margin_1end",
@@ -968,6 +969,7 @@ char * GTK_nativeFunctionNames[] = {
 	"gtk_1widget_1get_1preferred_1height_1for_1width",
 	"gtk_1widget_1get_1preferred_1size",
 	"gtk_1widget_1get_1preferred_1width_1for_1height",
+	"gtk_1widget_1get_1prev_1sibling",
 	"gtk_1widget_1get_1realized",
 	"gtk_1widget_1get_1scale_1factor",
 	"gtk_1widget_1get_1screen",
@@ -1028,6 +1030,7 @@ char * GTK_nativeFunctionNames[] = {
 	"gtk_1widget_1style_1get__J_3B_3IJ",
 	"gtk_1widget_1style_1get__J_3B_3JJ",
 	"gtk_1widget_1translate_1coordinates",
+	"gtk_1widget_1unparent",
 	"gtk_1window_1activate_1default",
 	"gtk_1window_1add_1accel_1group",
 	"gtk_1window_1deiconify",
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
index 420b414ed1..e5a4136060 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
@@ -949,6 +949,7 @@ typedef enum {
 	gtk_1widget_1get_1events_FUNC,
 	gtk_1widget_1get_1first_1child_FUNC,
 	gtk_1widget_1get_1has_1window_FUNC,
+	gtk_1widget_1get_1last_1child_FUNC,
 	gtk_1widget_1get_1mapped_FUNC,
 	gtk_1widget_1get_1margin_1bottom_FUNC,
 	gtk_1widget_1get_1margin_1end_FUNC,
@@ -966,6 +967,7 @@ typedef enum {
 	gtk_1widget_1get_1preferred_1height_1for_1width_FUNC,
 	gtk_1widget_1get_1preferred_1size_FUNC,
 	gtk_1widget_1get_1preferred_1width_1for_1height_FUNC,
+	gtk_1widget_1get_1prev_1sibling_FUNC,
 	gtk_1widget_1get_1realized_FUNC,
 	gtk_1widget_1get_1scale_1factor_FUNC,
 	gtk_1widget_1get_1screen_FUNC,
@@ -1026,6 +1028,7 @@ typedef enum {
 	gtk_1widget_1style_1get__J_3B_3IJ_FUNC,
 	gtk_1widget_1style_1get__J_3B_3JJ_FUNC,
 	gtk_1widget_1translate_1coordinates_FUNC,
+	gtk_1widget_1unparent_FUNC,
 	gtk_1window_1activate_1default_FUNC,
 	gtk_1window_1add_1accel_1group_FUNC,
 	gtk_1window_1deiconify_FUNC,
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
index c7cd359205..3d05358992 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
@@ -255,13 +255,36 @@ public class GTK extends OS {
 	/** @param widget cast=(GtkWidget *) */
 	public static final native boolean gtk_widget_get_sensitive(long widget);
 
-	/** @param widget cast=(GtkWidget *) */
-	/* [GTK4 only, if-def'd in os.h] */
+	/**
+	 * @method flags=dynamic
+	 * @param widget cast=(GtkWidget *)
+	 * */
+	/* [GTK4 only] */
 	public static final native long gtk_widget_get_first_child(long widget);
-
-	/** @param widget cast=(GtkWidget *) */
-	/* [GTK4 only, if-def'd in os.h] */
+	/**
+	 * @method flags=dynamic
+	 * @param widget cast=(GtkWidget *)
+	 * */
+	/* [GTK4 only] */
+	public static final native long gtk_widget_get_last_child(long widget);
+	/**
+	 * @method flags=dynamic
+	 * @param widget cast=(GtkWidget *)
+	 * */
+	/* [GTK4 only] */
 	public static final native long gtk_widget_get_next_sibling(long widget);
+	/**
+	 * @method flags=dynamic
+	 * @param widget cast=(GtkWidget *)
+	 * */
+	/* [GTK4 only] */
+	public static final native long gtk_widget_get_prev_sibling(long widget);
+	/**
+	 * @method flags=dynamic
+	 * @param widget cast=(GtkWidget *)
+	 * */
+	/* [GTK4 only] */
+	public static final native void gtk_widget_unparent(long widget);
 
 	/**
 	 * @param widget cast=(GtkWidget *)
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Composite.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Composite.java
index aa7a1fd4c1..82a53ae261 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Composite.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Composite.java
@@ -159,32 +159,44 @@ static int checkStyle (int style) {
 	return style;
 }
 
-Control [] _getChildren () {
-	long parentHandle = parentingHandle ();
-	//TODO: GTK4 no GTKContainer, and GtkWidget has no get_children function
-	long list = GTK.GTK4 ? 0 : GTK.gtk_container_get_children (parentHandle);
-	if (list == 0) return new Control [0];
-	int count = OS.g_list_length (list);
-	Control [] children = new Control [count];
-	int i = 0;
-	long temp = list;
-	while (temp != 0) {
-		long handle = OS.g_list_data (temp);
-		if (handle != 0) {
-			Widget widget = display.getWidget (handle);
-			if (widget != null && widget != this) {
-				if (widget instanceof Control) {
-					children [i++] = (Control) widget;
+Control[] _getChildren () {
+	long parentHandle = parentingHandle();
+
+	if (GTK.GTK4) {
+		ArrayList<Control> childrenList = new ArrayList<>();
+		for (long child = GTK.gtk_widget_get_first_child(parentHandle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			Widget childWidget = display.getWidget(child);
+			if (childWidget != null && childWidget instanceof Control && childWidget != this) {
+				childrenList.add((Control)childWidget);
+			}
+		}
+
+		return childrenList.toArray(new Control[childrenList.size()]);
+	} else {
+		long list = GTK.gtk_container_get_children (parentHandle);
+		if (list == 0) return new Control [0];
+		int count = OS.g_list_length (list);
+		Control [] children = new Control [count];
+		int i = 0;
+		long temp = list;
+		while (temp != 0) {
+			long handle = OS.g_list_data (temp);
+			if (handle != 0) {
+				Widget widget = display.getWidget (handle);
+				if (widget != null && widget != this) {
+					if (widget instanceof Control) {
+						children [i++] = (Control) widget;
+					}
 				}
 			}
+			temp = OS.g_list_next (temp);
 		}
-		temp = OS.g_list_next (temp);
+		OS.g_list_free (list);
+		if (i == count) return children;
+		Control [] newChildren = new Control [i];
+		System.arraycopy (children, 0, newChildren, 0, i);
+		return newChildren;
 	}
-	OS.g_list_free (list);
-	if (i == count) return children;
-	Control [] newChildren = new Control [i];
-	System.arraycopy (children, 0, newChildren, 0, i);
-	return newChildren;
 }
 
 Control [] _getTabList () {
@@ -745,14 +757,24 @@ public Control [] getChildren () {
 }
 
 int getChildrenCount () {
-	/*
-	* NOTE: The current implementation will count
-	* non-registered children.
-	*/
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return 0;
-	int count = OS.g_list_length (list);
-	OS.g_list_free (list);
+	int count = 0;
+
+	if (GTK.GTK4) {
+		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			count++;
+		}
+	} else {
+		/*
+		* NOTE: The current implementation will count
+		* non-registered children.
+		*/
+		long list = GTK.gtk_container_get_children(handle);
+		if (list != 0) {
+			count = OS.g_list_length(list);
+			OS.g_list_free(list);
+		}
+	}
+
 	return count;
 }
 
@@ -1445,56 +1467,49 @@ void connectFixedHandleDraw () {
  */
 void propagateDraw (long container, long cairo) {
 	if (container == fixedHandle) {
-		long list = GTK.gtk_container_get_children (container);
-		long temp = list;
-		while (temp != 0) {
-			long child = OS.g_list_data (temp);
-			if (child != 0) {
-				Widget widget = display.getWidget (child);
-				if (widget != this) {
-					if (noChildDrawing) {
-						Boolean childLowered = childrenLowered.get(widget);
-						if (childLowered == null) {
-							childrenLowered.put(widget, false);
-							childLowered = false;
-						}
-						GtkAllocation allocation = new GtkAllocation ();
-						GTK.gtk_widget_get_allocation(child, allocation);
-						if (allocation.y < 0) {
-							if (!childLowered) {
-								if (GTK.GTK4) {
-									long surface = gtk_widget_get_surface(child);
-									GDK.gdk_toplevel_lower(surface);
-								} else {
+		if (GTK.GTK4) {
+			for (long child = GTK.gtk_widget_get_first_child(container); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+				//TODO: GTK4 no gtk_container_propagate_draw. Possibly not required at all.
+			}
+		} else {
+			long list = GTK.gtk_container_get_children (container);
+			long temp = list;
+			while (temp != 0) {
+				long child = OS.g_list_data (temp);
+				if (child != 0) {
+					Widget widget = display.getWidget (child);
+					if (widget != this) {
+						if (noChildDrawing) {
+							Boolean childLowered = childrenLowered.get(widget);
+							if (childLowered == null) {
+								childrenLowered.put(widget, false);
+								childLowered = false;
+							}
+							GtkAllocation allocation = new GtkAllocation ();
+							GTK.gtk_widget_get_allocation(child, allocation);
+							if (allocation.y < 0) {
+								if (!childLowered) {
 									long window = gtk_widget_get_window(child);
 									GDK.gdk_window_lower(window);
+									childrenLowered.put(widget, true);
 								}
-								childrenLowered.put(widget, true);
-							}
-						} else {
-							if (childLowered) {
-								if (GTK.GTK4) {
-									long surface = gtk_widget_get_surface(child);
-									int width = GDK.gdk_surface_get_width(surface);
-									int height = GDK.gdk_surface_get_height(surface);
-									long layout = GDK.gdk_toplevel_layout_new(width, height);
-									GDK.gdk_toplevel_present(surface, width, height, layout);
-								} else {
+							} else {
+								if (childLowered) {
 									long window = gtk_widget_get_window(child);
 									GDK.gdk_window_raise(window);
+									childrenLowered.put(widget, false);
 								}
-								childrenLowered.put(widget, false);
+								GTK.gtk_container_propagate_draw(container, child, cairo);
 							}
+						} else {
 							GTK.gtk_container_propagate_draw(container, child, cairo);
 						}
-					} else {
-						GTK.gtk_container_propagate_draw(container, child, cairo);
 					}
 				}
+				temp = OS.g_list_next (temp);
 			}
-			temp = OS.g_list_next (temp);
+			OS.g_list_free (list);
 		}
-		OS.g_list_free (list);
 	}
 }
 
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
index 40d4390450..e012e61938 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
@@ -1431,27 +1431,41 @@ public void setRegion (Region region) {
 }
 
 void setRelations () {
-	long parentHandle = parent.parentingHandle ();
-	long list = GTK.gtk_container_get_children (parentHandle);
-	if (list == 0) return;
-	int count = OS.g_list_length (list);
-	if (count > 1) {
-		/*
-		 * the receiver is the last item in the list, so its predecessor will
-		 * be the second-last item in the list
-		 */
-		long handle = OS.g_list_nth_data (list, count - 2);
-		if (handle != 0) {
-			Widget widget = display.getWidget (handle);
-			if (widget != null && widget != this) {
-				if (widget instanceof Control) {
-					Control sibling = (Control)widget;
-					sibling.addRelation (this);
-				}
+	long parentHandle = parent.parentingHandle();
+	long handle = 0;
+
+	if (GTK.GTK4) {
+		int count = 0;
+		for (long child = GTK.gtk_widget_get_first_child(parentHandle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			count++;
+		}
+
+		if (count > 1) {
+			handle = GTK.gtk_widget_get_prev_sibling(GTK.gtk_widget_get_last_child(parentHandle));
+		}
+	} else {
+		long list = GTK.gtk_container_get_children (parentHandle);
+		if (list == 0) return;
+		int count = OS.g_list_length (list);
+		if (count > 1) {
+			/*
+			 * the receiver is the last item in the list, so its predecessor will
+			 * be the second-last item in the list
+			 */
+			handle = OS.g_list_nth_data (list, count - 2);
+		}
+		OS.g_list_free (list);
+	}
+
+	if (handle != 0) {
+		Widget widget = display.getWidget (handle);
+		if (widget != null && widget != this) {
+			if (widget instanceof Control) {
+				Control sibling = (Control)widget;
+				sibling.addRelation (this);
 			}
 		}
 	}
-	OS.g_list_free (list);
 }
 
 /**
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Menu.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Menu.java
index f9c3c9b7e6..1c3dbe9c49 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Menu.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Menu.java
@@ -13,6 +13,8 @@
  *******************************************************************************/
 package org.eclipse.swt.widgets;
 
+import java.util.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.events.*;
 import org.eclipse.swt.graphics.*;
@@ -561,14 +563,34 @@ public boolean getEnabled () {
  */
 public MenuItem getItem (int index) {
 	checkWidget();
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
-	int count = OS.g_list_length (list);
-	if (!(0 <= index && index < count)) error (SWT.ERROR_INVALID_RANGE);
-	long data = OS.g_list_nth_data (list, index);
-	OS.g_list_free (list);
-	if (data == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
-	return (MenuItem) display.getWidget (data);
+
+	if (GTK.GTK4) {
+		long itemHandle = GTK.gtk_widget_get_first_child(handle);
+		if (itemHandle == 0) error(SWT.ERROR_CANNOT_GET_ITEM);
+
+		int childIndex = 0;
+		while (itemHandle != 0) {
+			if (childIndex == index) {
+				break;
+			}
+			childIndex++;
+			itemHandle = GTK.gtk_widget_get_next_sibling(itemHandle);
+		}
+
+		if (index < 0 || index >= childIndex) error(SWT.ERROR_INVALID_RANGE);
+		if (itemHandle == 0) error(SWT.ERROR_CANNOT_GET_ITEM);
+
+		return (MenuItem) display.getWidget(itemHandle);
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
+		int count = OS.g_list_length (list);
+		if (!(0 <= index && index < count)) error (SWT.ERROR_INVALID_RANGE);
+		long data = OS.g_list_nth_data (list, index);
+		OS.g_list_free (list);
+		if (data == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
+		return (MenuItem) display.getWidget(data);
+	}
 }
 
 /**
@@ -583,11 +605,23 @@ public MenuItem getItem (int index) {
  */
 public int getItemCount () {
 	checkWidget();
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return 0;
-	int count = OS.g_list_length (list);
-	OS.g_list_free (list);
-	return Math.max (0, count);
+
+	int count = 0;
+	if (GTK.GTK4) {
+		long itemHandle = GTK.gtk_widget_get_first_child(handle);
+		if (itemHandle == 0) return 0;
+		while (itemHandle != 0) {
+			count++;
+			itemHandle = GTK.gtk_widget_get_next_sibling(itemHandle);
+		}
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) return 0;
+		count = OS.g_list_length (list);
+		OS.g_list_free (list);
+	}
+
+	return Math.max(0, count);
 }
 
 /**
@@ -608,25 +642,40 @@ public int getItemCount () {
  */
 public MenuItem [] getItems () {
 	checkWidget();
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return new MenuItem [0];
-	long originalList = list;
-	int count = OS.g_list_length (list);
-	MenuItem [] items = new MenuItem [count];
-	int index = 0;
-	for (int i=0; i<count; i++) {
-		long data = OS.g_list_data (list);
-		MenuItem item = (MenuItem) display.getWidget (data);
-		if (item != null) items [index++] = item;
-		list = OS.g_list_next (list);
-	}
-	OS.g_list_free (originalList);
-	if (index != items.length) {
-		MenuItem [] newItems = new MenuItem [index];
-		System.arraycopy (items, 0, newItems, 0, index);
-		items = newItems;
+
+	if (GTK.GTK4) {
+		long itemHandle = GTK.gtk_widget_get_first_child(handle);
+		if (itemHandle == 0) return new MenuItem[0];
+
+		ArrayList<MenuItem> items = new ArrayList<>();
+		while (itemHandle != 0) {
+			MenuItem item = (MenuItem) display.getWidget(itemHandle);
+			if (item != null) items.add(item);
+			itemHandle = GTK.gtk_widget_get_next_sibling(itemHandle);
+		}
+
+		return items.toArray(new MenuItem[items.size()]);
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) return new MenuItem [0];
+		long originalList = list;
+		int count = OS.g_list_length (list);
+		MenuItem [] items = new MenuItem [count];
+		int index = 0;
+		for (int i=0; i<count; i++) {
+			long data = OS.g_list_data (list);
+			MenuItem item = (MenuItem) display.getWidget (data);
+			if (item != null) items [index++] = item;
+			list = OS.g_list_next (list);
+		}
+		OS.g_list_free (originalList);
+		if (index != items.length) {
+			MenuItem [] newItems = new MenuItem [index];
+			System.arraycopy (items, 0, newItems, 0, index);
+			items = newItems;
+		}
+		return items;
 	}
-	return items;
 }
 
 @Override
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
index b957fa4421..db4b2b3548 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Shell.java
@@ -2898,12 +2898,19 @@ void showWidget () {
 			display.activeShell = this;
 			display.activePending = true;
 		}
-		long children = GTK.gtk_container_get_children (shellHandle), list = children;
-		while (list != 0) {
-			GTK.gtk_container_remove (shellHandle, OS.g_list_data (list));
-			list = OS.g_list_next(list);
+
+		if (GTK.GTK4) {
+			for (long child = GTK.gtk_widget_get_first_child(shellHandle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+				GTK.gtk_widget_unparent(child);
+			}
+		} else {
+			long list = GTK.gtk_container_get_children (shellHandle);
+			while (list != 0) {
+				GTK.gtk_container_remove (shellHandle, OS.g_list_data (list));
+				list = OS.g_list_next(list);
+			}
+			OS.g_list_free (list);
 		}
-		OS.g_list_free (list);
 	}
 
 	if (GTK.GTK4) {
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/TabFolder.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/TabFolder.java
index 768b0c23d7..d518cfaf43 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/TabFolder.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/TabFolder.java
@@ -14,6 +14,8 @@
 package org.eclipse.swt.widgets;
 
 
+import java.util.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.events.*;
 import org.eclipse.swt.graphics.*;
@@ -277,12 +279,19 @@ void createWidget (int index) {
 }
 
 void createItem (TabItem item, int index) {
-	long list = GTK.gtk_container_get_children (handle);
 	int itemCount = 0;
-	if (list != 0) {
-		itemCount = OS.g_list_length (list);
-		OS.g_list_free (list);
+	if (GTK.GTK4) {
+		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			itemCount++;
+		}
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list != 0) {
+			itemCount = OS.g_list_length (list);
+			OS.g_list_free (list);
+		}
 	}
+
 	if (!(0 <= index && index <= itemCount)) error (SWT.ERROR_INVALID_RANGE);
 	if (itemCount == items.length) {
 		TabItem [] newItems = new TabItem [items.length + 4];
@@ -373,40 +382,59 @@ long eventHandle () {
 
 @Override
 Control[] _getChildren() {
-	Control [] directChildren = super._getChildren ();
+	Control[] directChildren = super._getChildren();
 	int directCount = directChildren.length;
-	int count = items == null ? 0 : items.length;
-	Control [] children = new Control [count + directCount];
-	int i = 0;
-	for (int j = 0; j < count; j++) {
-		TabItem tabItem = items[j];
+	int itemCount = items == null ? 0 : items.length;
+	Control[] children = new Control[itemCount + directCount];
+
+	int childrenCount = 0;
+	for (int itemIndex = 0; itemIndex < itemCount; itemIndex++) {
+		TabItem tabItem = items[itemIndex];
 		if (tabItem != null && !tabItem.isDisposed()) {
 			long parentHandle = tabItem.pageHandle;
-			long list = GTK.gtk_container_get_children (parentHandle);
-			if (list != 0) {
-				long handle = OS.g_list_data (list);
-				if (handle != 0) {
-					Widget widget = display.getWidget (handle);
-					if (widget != null && widget != this) {
-						if (widget instanceof Control) {
-							children [i++] = (Control) widget;
+
+			if (GTK.GTK4) {
+				ArrayList<Control> childrenList = new ArrayList<>();
+				for (long child = GTK.gtk_widget_get_first_child(parentHandle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+					Widget childWidget = display.getWidget(child);
+					if (childWidget != null && childWidget instanceof Control && childWidget != this) {
+						childrenList.add((Control)childWidget);
+						childrenCount++;
+					}
+				}
+
+				children = childrenList.toArray(children);
+			} else {
+				long list = GTK.gtk_container_get_children (parentHandle);
+				if (list != 0) {
+					long handle = OS.g_list_data (list);
+					if (handle != 0) {
+						Widget widget = display.getWidget (handle);
+						if (widget != null && widget != this) {
+							if (widget instanceof Control) {
+								children [childrenCount++] = (Control) widget;
+							}
 						}
 					}
+					OS.g_list_free (list);
 				}
-				OS.g_list_free (list);
 			}
 		}
 	}
-	if (i == count + directCount) return children;
-	Control [] newChildren;
-	if (i == count) {
-		newChildren = children;
+
+	if (childrenCount == itemCount + directCount) {
+		return children;
 	} else {
-		newChildren = new Control [i + directCount];
-		System.arraycopy (children, 0, newChildren, 0, i);
+		Control[] newChildren;
+		if (childrenCount == itemCount) {
+			newChildren = children;
+		} else {
+			newChildren = new Control [childrenCount + directCount];
+			System.arraycopy (children, 0, newChildren, 0, childrenCount);
+		}
+		System.arraycopy (directChildren, 0, newChildren, childrenCount, directCount);
+		return newChildren;
 	}
-	System.arraycopy (directChildren, 0, newChildren, i, directCount);
-	return newChildren;
 }
 
 /**
@@ -427,11 +455,18 @@ Control[] _getChildren() {
 public TabItem getItem (int index) {
 	checkWidget();
 	if (!(0 <= index && index < getItemCount())) error (SWT.ERROR_INVALID_RANGE);
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
-	int itemCount = OS.g_list_length (list);
-	OS.g_list_free (list);
-	if (!(0 <= index && index < itemCount)) error (SWT.ERROR_CANNOT_GET_ITEM);
+
+	if (GTK.GTK4) {
+		long child = GTK.gtk_widget_get_first_child(handle);
+		if (child == 0) error(SWT.ERROR_CANNOT_GET_ITEM);
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) error (SWT.ERROR_CANNOT_GET_ITEM);
+		int itemCount = OS.g_list_length (list);
+		OS.g_list_free (list);
+		if (!(0 <= index && index < itemCount)) error (SWT.ERROR_CANNOT_GET_ITEM);
+	}
+
 	return items [index];
 }
 
@@ -456,10 +491,7 @@ public TabItem getItem (int index) {
 public TabItem getItem(Point point) {
 	checkWidget();
 	if (point == null) error (SWT.ERROR_NULL_ARGUMENT);
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return null;
-	int itemCount = OS.g_list_length (list);
-	OS.g_list_free (list);
+	int itemCount = getItemCount();
 	for (int i = 0; i < itemCount; i++) {
 		TabItem item = items[i];
 		Rectangle rect = item.getBounds();
@@ -480,10 +512,19 @@ public TabItem getItem(Point point) {
  */
 public int getItemCount () {
 	checkWidget();
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return 0;
-	int itemCount = OS.g_list_length (list);
-	OS.g_list_free (list);
+
+	int itemCount = 0;
+	if (GTK.GTK4) {
+		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			itemCount++;
+		}
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) return 0;
+		itemCount = OS.g_list_length (list);
+		OS.g_list_free (list);
+	}
+
 	return itemCount;
 }
 
@@ -604,14 +645,16 @@ void hookEvents () {
 public int indexOf (TabItem item) {
 	checkWidget();
 	if (item == null) error (SWT.ERROR_NULL_ARGUMENT);
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return -1;
-	int count = OS.g_list_length (list);
-	OS.g_list_free (list);
-	for (int i=0; i<count; i++) {
-		if (items [i] == item) return i;
+
+	int index = -1;
+	int count = getItemCount();
+	for (int i = 0; i < count; i++) {
+		if (items [i] == item) {
+			index = i;
+			break;
+		}
 	}
-	return -1;
+	return index;
 }
 
 @Override
@@ -621,12 +664,7 @@ Point minimumSize (int wHint, int hHint, boolean flushCache) {
 	for (int i=0; i<children.length; i++) {
 		Control child = children [i];
 		int index = 0;
-		int count = 0;
-		long list = GTK.gtk_container_get_children (handle);
-		if (list != 0) {
-			count = OS.g_list_length (list);
-			OS.g_list_free (list);
-		}
+		int count = getItemCount();
 		while (index < count) {
 			if (items [index].control == child) break;
 			index++;
@@ -727,14 +765,11 @@ public void removeSelectionListener (SelectionListener listener) {
 @Override
 void reskinChildren (int flags) {
 	if (items != null) {
-		long list = GTK.gtk_container_get_children (handle);
-		if (list != 0){
-			int count = OS.g_list_length (list);
-			OS.g_list_free (list);
-			for (int i=0; i<count; i++) {
-				TabItem item = items [i];
-				if (item != null) item.reskin (flags);
-			}
+		int count = getItemCount();
+
+		for (int i = 0; i < count; i++) {
+			TabItem item = items [i];
+			if (item != null) item.reskin(flags);
 		}
 	}
 	super.reskinChildren (flags);
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Table.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Table.java
index 1b80a4060b..bb61b30a0f 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Table.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Table.java
@@ -4174,23 +4174,26 @@ public void showSelection () {
 @Override
 void updateScrollBarValue (ScrollBar bar) {
 	super.updateScrollBarValue (bar);
-	/*
-	*  Bug in GTK. Scrolling changes the XWindow position
-	* and makes the child widgets appear to scroll even
-	* though when queried their position is unchanged.
-	* The fix is to queue a resize event for each child to
-	* force the position to be corrected.
-	*/
-	long parentHandle = parentingHandle ();
-	long list = GTK.gtk_container_get_children (parentHandle);
-	if (list == 0) return;
-	long temp = list;
-	while (temp != 0) {
-		long widget = OS.g_list_data (temp);
-		if (widget != 0) GTK.gtk_widget_queue_resize  (widget);
-		temp = OS.g_list_next (temp);
+
+	if (!GTK.GTK4) {
+		/*
+		*  Bug in GTK. Scrolling changes the XWindow position
+		* and makes the child widgets appear to scroll even
+		* though when queried their position is unchanged.
+		* The fix is to queue a resize event for each child to
+		* force the position to be corrected.
+		*/
+		long parentHandle = parentingHandle ();
+		long list = GTK.gtk_container_get_children (parentHandle);
+		if (list == 0) return;
+		long temp = list;
+		while (temp != 0) {
+			long widget = OS.g_list_data (temp);
+			if (widget != 0) GTK.gtk_widget_queue_resize  (widget);
+			temp = OS.g_list_next (temp);
+		}
+		OS.g_list_free (list);
 	}
-	OS.g_list_free (list);
 }
 
 @Override
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolBar.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolBar.java
index d2cfb170bc..2ca40d308c 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolBar.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolBar.java
@@ -14,6 +14,8 @@
 package org.eclipse.swt.widgets;
 
 
+import java.util.*;
+
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.internal.*;
@@ -339,10 +341,19 @@ ToolItem getItemInPixels (Point point) {
  */
 public int getItemCount () {
 	checkWidget();
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return 0;
-	int itemCount = OS.g_list_length (list);
-	OS.g_list_free (list);
+
+	int itemCount = 0;
+	if (GTK.GTK4) {
+		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			itemCount++;
+		}
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) return 0;
+		itemCount = OS.g_list_length (list);
+		OS.g_list_free (list);
+	}
+
 	return itemCount;
 }
 
@@ -367,26 +378,38 @@ public ToolItem [] getItems () {
 	return _getItems ();
 }
 
-ToolItem [] _getItems () {
-	long list = GTK.gtk_container_get_children (handle);
-	if (list == 0) return new ToolItem [0];
-	int count = OS.g_list_length (list);
-	ToolItem [] items = new ToolItem [count];
-	long originalList = list;
-	int index = 0;
-	for (int i=0; i<count; i++) {
-		long data = OS.g_list_data (list);
-		Widget widget = display.getWidget (data);
-		if (widget != null) items [index++] = (ToolItem) widget;
-		list = OS.g_list_next (list);
-	}
-	OS.g_list_free (originalList);
-	if (index != items.length) {
-		ToolItem [] newItems = new ToolItem [index];
-		System.arraycopy (items, 0, newItems, 0, index);
-		items = newItems;
+ToolItem[] _getItems () {
+	if (GTK.GTK4) {
+		ArrayList<ToolItem> childrenList = new ArrayList<>();
+		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
+			Widget childWidget = display.getWidget(child);
+			if (childWidget != null) {
+				childrenList.add((ToolItem)childWidget);
+			}
+		}
+
+		return childrenList.toArray(new ToolItem[childrenList.size()]);
+	} else {
+		long list = GTK.gtk_container_get_children (handle);
+		if (list == 0) return new ToolItem [0];
+		int count = OS.g_list_length (list);
+		ToolItem [] items = new ToolItem [count];
+		long originalList = list;
+		int index = 0;
+		for (int i=0; i<count; i++) {
+			long data = OS.g_list_data (list);
+			Widget widget = display.getWidget (data);
+			if (widget != null) items [index++] = (ToolItem) widget;
+			list = OS.g_list_next (list);
+		}
+		OS.g_list_free (originalList);
+		if (index != items.length) {
+			ToolItem [] newItems = new ToolItem [index];
+			System.arraycopy (items, 0, newItems, 0, index);
+			items = newItems;
+		}
+		return items;
 	}
-	return items;
 }
 
 /**
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolItem.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolItem.java
index 643556383d..cee52d9cae 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolItem.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolItem.java
@@ -211,21 +211,24 @@ void createHandle (int index) {
 			if (GTK.GTK4) {
 				handle = GTK.gtk_menu_button_new();
 			} else {
-				handle = GTK.gtk_menu_tool_button_new (0, null);
+				handle = GTK.gtk_menu_tool_button_new(0, null);
 			}
+			if (handle == 0) error(SWT.ERROR_NO_HANDLES);
 
-			if (handle == 0) error (SWT.ERROR_NO_HANDLES);
 			/*
 			 * Feature in GTK. The arrow button of DropDown tool-item is
 			 * disabled when it does not contain menu. The fix is to
 			 * find the arrow button handle and enable it.
 			 */
-			long child = GTK.gtk_bin_get_child (handle);
-			long list = GTK.gtk_container_get_children (child);
-			arrowHandle = OS.g_list_nth_data (list, 1);
-			if (arrowHandle != 0) {
-				GTK.gtk_widget_set_sensitive (arrowHandle, true);
+			if (GTK.GTK4) {
+				arrowHandle = GTK.gtk_widget_get_first_child(handle);
+			} else {
+				long child = GTK.gtk_bin_get_child(handle);
+				long list = GTK.gtk_container_get_children(child);
+				arrowHandle = OS.g_list_nth_data(list, 1);
 			}
+			if (arrowHandle != 0) GTK.gtk_widget_set_sensitive (arrowHandle, true);
+
 			break;
 		case SWT.RADIO:
 			/*
@@ -806,9 +809,18 @@ void hookEvents () {
 	 */
 	eventHandle = GTK.gtk_bin_get_child(handle);
 	if ((style & SWT.DROP_DOWN) != 0) {
-		long list = GTK.gtk_container_get_children(eventHandle);
-		eventHandle = OS.g_list_nth_data(list, 0);
-		if (arrowHandle != 0) OS.g_signal_connect_closure (arrowHandle, OS.clicked, display.getClosure (CLICKED), false);
+		if (GTK.GTK4) {
+			eventHandle = GTK.gtk_widget_get_first_child(handle);
+			if (arrowHandle != 0) {
+				long clickGesture = GTK.gtk_gesture_click_new();
+				OS.g_signal_connect(clickGesture, OS.pressed, display.gesturePressReleaseProc, GESTURE_PRESSED);
+				GTK.gtk_widget_add_controller(arrowHandle, clickGesture);
+			}
+		} else {
+			long list = GTK.gtk_container_get_children(eventHandle);
+			eventHandle = OS.g_list_nth_data(list, 0);
+			if (arrowHandle != 0) OS.g_signal_connect_closure (arrowHandle, OS.clicked, display.getClosure (CLICKED), false);
+		}
 	}
 	OS.g_signal_connect_closure (handle, OS.create_menu_proxy, display.getClosure (CREATE_MENU_PROXY), false);
 	if (GTK.GTK4) {
@@ -1373,13 +1385,17 @@ public void setToolTipText (String string) {
 }
 
 void setToolTipText (Shell shell, String newString) {
-	long child = GTK.gtk_bin_get_child (handle);
-	if ((style & SWT.DROP_DOWN) != 0) {
-		long list = GTK.gtk_container_get_children (child);
-		child = OS.g_list_nth_data (list, 0);
-		if (arrowHandle != 0) shell.setToolTipText (arrowHandle, newString);
+	if (GTK.GTK4) {
+		shell.setToolTipText(handle, newString);
+	} else {
+		long child = GTK.gtk_bin_get_child (handle);
+		if ((style & SWT.DROP_DOWN) != 0) {
+			long list = GTK.gtk_container_get_children (child);
+			child = OS.g_list_nth_data (list, 0);
+			if (arrowHandle != 0) shell.setToolTipText (arrowHandle, newString);
+		}
+		shell.setToolTipText (child != 0 ? child : handle, newString);
 	}
-	shell.setToolTipText (child != 0 ? child : handle, newString);
 }
 
 /**
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
index 5a8fe0a2d7..b481de7fab 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
@@ -4160,23 +4160,26 @@ public void showItem (TreeItem item) {
 @Override
 void updateScrollBarValue (ScrollBar bar) {
 	super.updateScrollBarValue (bar);
-	/*
-	* Bug in GTK. Scrolling changes the XWindow position
-	* and makes the child widgets appear to scroll even
-	* though when queried their position is unchanged.
-	* The fix is to queue a resize event for each child to
-	* force the position to be corrected.
-	*/
-	long parentHandle = parentingHandle ();
-	long list = GTK.gtk_container_get_children (parentHandle);
-	if (list == 0) return;
-	long temp = list;
-	while (temp != 0) {
-		long widget = OS.g_list_data (temp);
-		if (widget != 0) GTK.gtk_widget_queue_resize  (widget);
-		temp = OS.g_list_next (temp);
+
+	if (!GTK.GTK4) {
+		/*
+		* Bug in GTK. Scrolling changes the XWindow position
+		* and makes the child widgets appear to scroll even
+		* though when queried their position is unchanged.
+		* The fix is to queue a resize event for each child to
+		* force the position to be corrected.
+		*/
+		long parentHandle = parentingHandle ();
+		long list = GTK.gtk_container_get_children (parentHandle);
+		if (list == 0) return;
+		long temp = list;
+		while (temp != 0) {
+			long widget = OS.g_list_data (temp);
+			if (widget != 0) GTK.gtk_widget_queue_resize  (widget);
+			temp = OS.g_list_next (temp);
+		}
+		OS.g_list_free (list);
 	}
-	OS.g_list_free (list);
 }
 
 @Override