update actions for textbox ensure caret visible

desktop/gui.cpp

@@ -106,7 +106,7 @@ EsElement *UIFindHoverElementRecursively(EsElement *element, int offsetX, int of
 const EsStyle *UIGetDefaultStyleVariant(const EsStyle *style, EsElement *parent);
 void AccessKeysCenterHint(EsElement *element, EsMessage *message);
 void UIRemoveFocusFromElement(EsElement *oldFocus);
-void UIQueueEnsureVisibleMessage(EsElement *element);
+void UIQueueEnsureVisibleMessage(EsElement *element, bool center);
 void ColorPickerCreate(EsElement *parent, struct ColorPickerHost host, uint32_t initialColor, bool showTextbox);
 
 void InspectorSetup(EsWindow *window);
@@ -134,6 +134,7 @@ void InspectorNotifyElementContentChanged(EsElement *element);
 #define UI_STATE_ANIMATING		(1 <<  9)
 #define UI_STATE_CHECK_VISIBLE		(1 << 10)
 #define UI_STATE_QUEUED_ENSURE_VISIBLE	(1 << 11)
+#define UI_STATE_ENSURE_VISIBLE_CENTER  (1 << 12)
 
 // Behaviour modifiers:
 #define UI_STATE_STRONG_PRESSED		(1 << 12)
@@ -2588,6 +2589,8 @@ struct Scrollbar : EsElement {
 };
 
 void ScrollbarLayout(Scrollbar *scrollbar) {
+	// TODO Do this as an UpdateAction?
+
 	if (scrollbar->viewportSize >= scrollbar->contentSize || scrollbar->viewportSize <= 0 || scrollbar->contentSize <= 0) {
 		EsElementSetDisabled(scrollbar, true);
 	} else {
@@ -3194,12 +3197,16 @@ int ProcessPanelMessage(EsElement *element, EsMessage *message) {
 		}
 	} else if (message->type == ES_MSG_ENSURE_VISIBLE) {
 		if (panel->scroll.enabled[0] || panel->scroll.enabled[1]) {
-			EsElement *child = message->child, *e = child;
+			EsElement *child = message->ensureVisible.descendent, *e = child;
-			int offsetX = panel->scroll.position[0], offsetY = panel->scroll.position[1];
+			int offsetX = 0, offsetY = 0;
 			while (e != element) offsetX += e->offsetX, offsetY += e->offsetY, e = e->parent;
 			EsRectangle bounds = panel->GetBounds();
-			panel->scroll.SetX(offsetX + child->width / 2 - bounds.r / 2);
+
-			panel->scroll.SetY(offsetY + child->height / 2 - bounds.b / 2);
+			if (message->ensureVisible.center || !EsRectangleContainsAll(bounds, ES_RECT_4PD(offsetX, offsetY, child->width, child->height))) {
+				panel->scroll.SetX(offsetX + panel->scroll.position[0] + child->width / 2 - bounds.r / 2);
+				panel->scroll.SetY(offsetY + panel->scroll.position[1] + child->height / 2 - bounds.b / 2);
+			}
+
 			return ES_HANDLED;
 		} else {
 			// This is not a scroll container, so don't update the child element being made visible.
@@ -6161,12 +6168,14 @@ bool EsElementIsFocused(EsElement *element) {
 
 void UISendEnsureVisibleMessage(EsElement *element, EsGeneric) {
 	EsElement *child = element, *e = element;
+	bool center = element->state & UI_STATE_ENSURE_VISIBLE_CENTER;
 	EsAssert(element->state & UI_STATE_QUEUED_ENSURE_VISIBLE);
-	element->state &= ~UI_STATE_QUEUED_ENSURE_VISIBLE;
+	element->state &= ~(UI_STATE_QUEUED_ENSURE_VISIBLE | UI_STATE_ENSURE_VISIBLE_CENTER);
 
 	while (e->parent) {
 		EsMessage m = { ES_MSG_ENSURE_VISIBLE };
-		m.child = child;
+		m.ensureVisible.descendent = child;
+		m.ensureVisible.center = center;
 		e = e->parent;
 
 		if (ES_HANDLED == EsMessageSend(e, &m)) {
@@ -6177,7 +6186,11 @@ void UISendEnsureVisibleMessage(EsElement *element, EsGeneric) {
 	EsAssert(~element->state & UI_STATE_QUEUED_ENSURE_VISIBLE);
 }
 
-void UIQueueEnsureVisibleMessage(EsElement *element) {
+void UIQueueEnsureVisibleMessage(EsElement *element, bool center) {
+	if (center) {
+		element->state |= UI_STATE_ENSURE_VISIBLE_CENTER;
+	}
+
 	if (~element->state & UI_STATE_QUEUED_ENSURE_VISIBLE) {
 		element->state |= UI_STATE_QUEUED_ENSURE_VISIBLE;
 		UpdateAction action = {};
@@ -6258,7 +6271,7 @@ void EsElementFocus(EsElement *element, uint32_t flags) {
 	// Ensure the element is visible.
 
 	if ((flags & ES_ELEMENT_FOCUS_ENSURE_VISIBLE) && element) {
-		UIQueueEnsureVisibleMessage(element);
+		UIQueueEnsureVisibleMessage(element, true);
 	}
 }
 

desktop/os.header

@@ -1632,6 +1632,11 @@ struct EsMessageScroll {
 	int scroll, previous;
 };
 
+struct EsMessageEnsureVisible {
+	bool center; // If false, only center the element if it is partially obscured.
+	EsElement *descendent;
+};
+
 // List view messages.
 
 struct EsMessageIterateIndex {
@@ -1862,11 +1867,12 @@ struct EsMessage {
 		EsMessageScrollWheel scrollWheel;
 		EsMessageWindowActivated windowActivated;
 		EsMessageScroll scroll;
+		EsMessageEnsureVisible ensureVisible;
 		const EsStyle *childStyleVariant;
 		EsRectangle *accessKeyHintBounds;
 		EsPainter *painter;
-		EsElement *child;
 		EsCursorStyle cursorStyle;
+		EsElement *child;
 
 		// List view messages:
 		EsMessageIterateIndex iterateIndex;

desktop/text.cpp

@@ -2919,6 +2919,8 @@ struct EsTextbox : EsElement {
 	char *editStartContent;
 	int32_t editStartContentBytes;
 
+	bool ensureCaretVisibleQueued;
+
 	EsUICallback overlayCallback;
 	EsGeneric overlayData;
 
@@ -2926,7 +2928,7 @@ struct EsTextbox : EsElement {
 	uintptr_t activeLineAllocated;
 	int32_t activeLineIndex, activeLineStart, activeLineOldBytes, activeLineBytes;
 
-	int32_t longestLine, longestLineWidth; // To set the horizontal scrollbar's size.
+	int32_t longestLine, longestLineWidth; // To set the horizontal scroll bar's size.
 
 	TextboxCaret carets[2]; // carets[1] is the actual caret; carets[0] is the selection anchor.
 	TextboxCaret wordSelectionAnchor, wordSelectionAnchor2;
@@ -3341,11 +3343,22 @@ TextboxVisibleLine *TextboxGetVisibleLine(EsTextbox *textbox, int32_t documentLi
 		? nullptr : &textbox->visibleLines[documentLineIndex - textbox->firstVisibleLine];
 }
 
-void EsTextboxEnsureCaretVisible(EsTextbox *textbox, bool verticallyCenter) {
+void TextboxEnsureCaretVisibleActionCallback(EsElement *element, EsGeneric context) {
+	EsTextbox *textbox = (EsTextbox *) element;
+	bool verticallyCenter = context.u;
 	TextboxCaret caret = textbox->carets[1];
-	EsRectangle bounds = textbox->GetBounds();
 
-	{
+	EsPrint("TextboxEnsureCaretVisibleActionCallback ------------\n");
+
+	for (uintptr_t i = 0; i < 3; i++) {
+		// ScrollPane::SetY causes ES_MSG_SCROLL_Y to get sent to the textbox.
+		// This causes a TextboxRefreshVisibleLines, which may cause new lines to added.
+		// If these lines had not been previously horizontally measured, this will then occur.
+		// This then causes a ScrollPane::Refresh for the new horizontal width.
+		// If this causes the horizontal scroll bar to appear, then the caret may no longer be fully visible.
+		// Therefore, we repeat up to 3 times to ensure that the caret is definitely fully visible.
+		
+		EsRectangle bounds = textbox->GetBounds();
 		DocumentLine *line = &textbox->lines[caret.line];
 		int caretY = line->yPosition + textbox->insets.t;
 
@@ -3364,13 +3377,21 @@ void EsTextboxEnsureCaretVisible(EsTextbox *textbox, bool verticallyCenter) {
 				}
 			}
 
+			if (textbox->scroll.position[1] != scrollY) {
+				EsPrint("     new scroll %d\n", scrollY);
 				textbox->scroll.SetY(scrollY);
+			} else {
+				break;
+			}
+		} else {
+			break;
 		}
 	}
 
 	TextboxVisibleLine *visibleLine = TextboxGetVisibleLine(textbox, caret.line);
 
 	if (visibleLine) {
+		EsRectangle bounds = textbox->GetBounds();
 		DocumentLine *line = &textbox->lines[caret.line];
 		int scrollX = textbox->scroll.position[0];
 		int viewportWidth = bounds.r;
@@ -3386,7 +3407,19 @@ void EsTextboxEnsureCaretVisible(EsTextbox *textbox, bool verticallyCenter) {
 		textbox->scroll.SetX(scrollX);
 	}
 
-	UIQueueEnsureVisibleMessage(textbox);
+	UIQueueEnsureVisibleMessage(textbox, false);
+	textbox->ensureCaretVisibleQueued = false;
+}
+
+void EsTextboxEnsureCaretVisible(EsTextbox *textbox, bool verticallyCenter) {
+	if (!textbox->ensureCaretVisibleQueued) {
+		UpdateAction action = {};
+		action.element = textbox;
+		action.callback = TextboxEnsureCaretVisibleActionCallback;
+		action.context.u = verticallyCenter;
+		textbox->window->updateActions.Add(action);
+		textbox->ensureCaretVisibleQueued = true;
+	}
 }
 
 bool TextboxMoveCaret(EsTextbox *textbox, TextboxCaret *caret, bool right, int moveType, bool strongWhitespace = false) {
@@ -3667,6 +3700,7 @@ void TextboxUndoItemCallback(const void *item, EsUndoManager *manager, EsMessage
 		textbox->carets[0] = header->caretsBefore[0];
 		textbox->carets[1] = header->caretsBefore[1];
 		EsTextboxInsert(textbox, (const char *) (header + 1), header->insertBytes, true);
+		EsTextboxEnsureCaretVisible(textbox);
 	} else if (message->type == ES_MSG_UNDO_CANCEL) {
 		// Nothing to do.
 	}