Bug [#2087]. Fix flicker when inserting primary selection on GTK.

3 files changed, 48 insertions, 28 deletions

diff --git a/doc/ScintillaHistory.html b/doc/ScintillaHistory.html
index 381dc4ecd..6f08fe033 100644
--- a/doc/ScintillaHistory.html
+++ b/doc/ScintillaHistory.html
@@ -571,6 +571,10 @@
 	Implement high-priority idle on Win32 to make redraw smoother and more efficient.
 	</li>
  	<li>
+	Fix flicker when inserting primary selection on GTK.
+	<a href="https://sourceforge.net/p/scintilla/bugs/2087/">Bug #2087</a>.
+	</li>
+ 	<li>
 	Avoid potential long hangs with idle styling for huge documents on Cocoa and GTK.
 	</li>
     <ul>
diff --git a/gtk/ScintillaGTK.cxx b/gtk/ScintillaGTK.cxx
index f213c0097..ccf2498fa 100644
--- a/gtk/ScintillaGTK.cxx
+++ b/gtk/ScintillaGTK.cxx
@@ -1262,37 +1262,47 @@ void ScintillaGTK::Copy() {
 	}
 }
 
-void ScintillaGTK::Paste() {
-	atomSought = atomUTF8;
-	GtkClipboard *clipBoard =
-		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), atomClipboard);
-	if (clipBoard == nullptr)
-		return;
+namespace {
 
-	// helper class for the asynchronous paste not to risk calling in a destroyed ScintillaGTK
-	class Helper : GObjectWatcher {
-		ScintillaGTK *sci;
+// Helper class for the asynchronous paste not to risk calling in a destroyed ScintillaGTK
 
-		void Destroyed() override {
-			sci = nullptr;
-		}
+class SelectionReceiver : GObjectWatcher {
+	ScintillaGTK *sci;
 
-	public:
-		Helper(ScintillaGTK *sci_) :
-			GObjectWatcher(G_OBJECT(PWidget(sci_->wMain))),
-			sci(sci_) {
-		}
+	void Destroyed() override {
+		sci = nullptr;
+	}
 
-		static void ClipboardReceived(GtkClipboard *, GtkSelectionData *selection_data, gpointer data) {
-			Helper *self = static_cast<Helper *>(data);
-			if (self->sci) {
-				self->sci->ReceivedSelection(selection_data);
-			}
-			delete self;
+public:
+	SelectionReceiver(ScintillaGTK *sci_) :
+		GObjectWatcher(G_OBJECT(sci_->MainObject())),
+		sci(sci_) {
+	}
+
+	static void ClipboardReceived(GtkClipboard *, GtkSelectionData *selection_data, gpointer data) {
+		SelectionReceiver *self = static_cast<SelectionReceiver *>(data);
+		if (self->sci) {
+			self->sci->ReceivedSelection(selection_data);
 		}
-	};
+		delete self;
+	}
+};
+
+}
+
+void ScintillaGTK::RequestSelection(GdkAtom atomSelection) {
+	atomSought = atomUTF8;
+	GtkClipboard *clipBoard =
+		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), atomSelection);
+	if (clipBoard) {
+		gtk_clipboard_request_contents(clipBoard, atomSought,
+					       SelectionReceiver::ClipboardReceived,
+					       new SelectionReceiver(this));
+	}
+}
 
-	gtk_clipboard_request_contents(clipBoard, atomSought, Helper::ClipboardReceived, new Helper(this));
+void ScintillaGTK::Paste() {
+	RequestSelection(atomClipboard);
 }
 
 void ScintillaGTK::CreateCallTipWindow(PRectangle rc) {
@@ -1423,6 +1433,10 @@ void ScintillaGTK::GetGtkSelectionText(GtkSelectionData *selectionData, Selectio
 	}
 }
 
+GObject *ScintillaGTK::MainObject() const noexcept {
+	return G_OBJECT(PWidget(wMain));
+}
+
 void ScintillaGTK::ReceivedSelection(GtkSelectionData *selection_data) {
 	try {
 		if ((SelectionOfGSD(selection_data) == atomClipboard) ||
@@ -1737,9 +1751,7 @@ gint ScintillaGTK::PressThis(GdkEventButton *event) {
 
 			sel.Clear();
 			SetSelection(pos, pos);
-			atomSought = atomUTF8;
-			gtk_selection_convert(GTK_WIDGET(PWidget(wMain)), GDK_SELECTION_PRIMARY,
-					      atomSought, event->time);
+			RequestSelection(GDK_SELECTION_PRIMARY);
 		} else if (event->button == 3) {
 			if (!PointInSelection(pt))
 				SetEmptySelection(PositionFromLocation(pt));
diff --git a/gtk/ScintillaGTK.h b/gtk/ScintillaGTK.h
index 501903b42..c175192f9 100644
--- a/gtk/ScintillaGTK.h
+++ b/gtk/ScintillaGTK.h
@@ -127,13 +127,17 @@ private:
 	int KeyDefault(int key, int modifiers) override;
 	void CopyToClipboard(const SelectionText &selectedText) override;
 	void Copy() override;
+	void RequestSelection(GdkAtom atomSelection);
 	void Paste() override;
 	void CreateCallTipWindow(PRectangle rc) override;
 	void AddToPopUp(const char *label, int cmd = 0, bool enabled = true) override;
 	bool OwnPrimarySelection();
 	void ClaimSelection() override;
 	void GetGtkSelectionText(GtkSelectionData *selectionData, SelectionText &selText);
+public:	// Public for SelectionReceiver
+	GObject *MainObject() const noexcept;
 	void ReceivedSelection(GtkSelectionData *selection_data);
+private:
 	void ReceivedDrop(GtkSelectionData *selection_data);
 	static void GetSelection(GtkSelectionData *selection_data, guint info, SelectionText *text);
 	void StoreOnClipboard(SelectionText *clipText);