BColumnListView: Resolve column resizing drawing glitch (wider than 600px)

* use of a shared bitmap buffer in OutlineView and TitleView
* dynamically increase of the bitmap buffer after adding a column or a row

Change-Id: I4feddf636fb1446c29e60353b8f70fc084833731
Reviewed-on: https://review.haiku-os.org/c/haiku/+/7176
Reviewed-by: John Scipione <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>
Reviewed-by: Stefano Ceccherini <[email protected]>
Tested-by: Commit checker robot <[email protected]>

src/kits/interface/ColumnListView.cpp

@@ -144,10 +144,34 @@ static const float kDropHighlightLineHeight = 2.0;
 
 static const uint32 kToggleColumn = 'BTCL';
 
+
+#ifdef DOUBLE_BUFFERED_COLUMN_RESIZE
+
+class ColumnResizeBufferView : public BView
+{
+public:
+							ColumnResizeBufferView();
+	virtual					~ColumnResizeBufferView();
+			void			UpdateMaxWidth(float width);
+			void			UpdateMaxHeight(float height);
+			bool			Lock();
+			void			Unlock();
+			const BBitmap* 	Bitmap();
+private:
+			void			_InitBitmap();
+			void			_FreeBitmap();
+
+			BBitmap*		fDrawBuffer;
+};
+
+#endif
+
+
 class BRowContainer : public BObjectList<BRow>
 {
 };
 
+
 class TitleView : public BView {
 	typedef BView _inherited;
 public:
@@ -198,10 +222,6 @@ private:
 //			float				fColumnsWidth;
 			BRect				fVisibleRect;
 
-#if DOUBLE_BUFFERED_COLUMN_RESIZE
-			BBitmap*			fDrawBuffer;
-			BView*				fDrawBufferView;
-#endif
 
 			enum {
 				INACTIVE,
@@ -292,6 +312,10 @@ public:
 	virtual void				MouseUp(BPoint where);
 	virtual void				MessageReceived(BMessage* message);
 
+#if DOUBLE_BUFFERED_COLUMN_RESIZE
+			ColumnResizeBufferView* ResizeBufferView();
+#endif
+
 private:
 			bool				SortList(BRowContainer* list, bool isVisible);
 	static	int32				DeepSortThreadEntry(void* outlineView);
@@ -311,8 +335,7 @@ private:
 			BRect				fVisibleRect;
 
 #if DOUBLE_BUFFERED_COLUMN_RESIZE
-			BBitmap*			fDrawBuffer;
+			ColumnResizeBufferView* fResizeBufferView;
-			BView*				fDrawBufferView;
 #endif
 
 			BRow*				fFocusRow;
@@ -391,6 +414,101 @@ private:
 using namespace BPrivate;
 
 
+#ifdef DOUBLE_BUFFERED_COLUMN_RESIZE
+
+ColumnResizeBufferView::ColumnResizeBufferView()
+	: BView(BRect(0, 0, 600, 35), "double_buffer_view", B_FOLLOW_ALL_SIDES, 0), fDrawBuffer(NULL)
+{
+	_InitBitmap();
+}
+
+
+ColumnResizeBufferView::~ColumnResizeBufferView()
+{
+	_FreeBitmap();
+}
+
+
+void
+ColumnResizeBufferView::UpdateMaxWidth(float width)
+{
+	Lock();
+	BRect bounds = Bounds();
+	Unlock();
+
+	if (width > bounds.Width()) {
+		Lock();
+		ResizeTo(width, bounds.Height());
+		Unlock();
+		_InitBitmap();
+	}
+}
+
+
+void
+ColumnResizeBufferView::UpdateMaxHeight(float height)
+{
+	Lock();
+	BRect bounds = Bounds();
+	Unlock();
+
+	if (height > bounds.Height()) {
+		Lock();
+		ResizeTo(bounds.Width(), height);
+		Unlock();
+		_InitBitmap();
+	}
+}
+
+
+bool
+ColumnResizeBufferView::Lock()
+{
+	return fDrawBuffer->Lock();
+}
+
+
+void
+ColumnResizeBufferView::Unlock()
+{
+	fDrawBuffer->Unlock();
+}
+
+
+const BBitmap*
+ColumnResizeBufferView::Bitmap()
+{
+	return fDrawBuffer;
+}
+
+
+void
+ColumnResizeBufferView::_InitBitmap()
+{
+	_FreeBitmap();
+
+	fDrawBuffer = new BBitmap(Bounds(), B_RGB32, true);
+	fDrawBuffer->Lock();
+	fDrawBuffer->AddChild(this);
+	fDrawBuffer->Unlock();
+}
+
+
+void
+ColumnResizeBufferView::_FreeBitmap()
+{
+	if (fDrawBuffer) {
+		fDrawBuffer->Lock();
+		fDrawBuffer->RemoveChild(this);
+		fDrawBuffer->Unlock();
+		delete fDrawBuffer;
+		fDrawBuffer = NULL;
+	}
+}
+
+#endif
+
+
 BField::BField()
 {
 }
@@ -2223,17 +2341,6 @@ TitleView::TitleView(BRect rect, OutlineView* horizontalSlave,
 {
 	SetViewColor(B_TRANSPARENT_COLOR);
 
-#if DOUBLE_BUFFERED_COLUMN_RESIZE
-	// xxx this needs to be smart about the size of the backbuffer.
-	BRect doubleBufferRect(0, 0, 600, 35);
-	fDrawBuffer = new BBitmap(doubleBufferRect, B_RGB32, true);
-	fDrawBufferView = new BView(doubleBufferRect, "double_buffer_view",
-		B_FOLLOW_ALL_SIDES, 0);
-	fDrawBuffer->Lock();
-	fDrawBuffer->AddChild(fDrawBufferView);
-	fDrawBuffer->Unlock();
-#endif
-
 	fUpSortArrow = new BBitmap(BRect(0, 0, 7, 7), B_CMAP8);
 	fDownSortArrow = new BBitmap(BRect(0, 0, 7, 7), B_CMAP8);
 
@@ -2254,9 +2361,6 @@ TitleView::~TitleView()
 	delete fColumnPop;
 	fColumnPop = NULL;
 
-#if DOUBLE_BUFFERED_COLUMN_RESIZE
-	delete fDrawBuffer;
-#endif
 	delete fUpSortArrow;
 	delete fDownSortArrow;
 
@@ -2270,6 +2374,9 @@ TitleView::~TitleView()
 void
 TitleView::ColumnAdded(BColumn* column)
 {
+#ifdef DOUBLE_BUFFERED_COLUMN_RESIZE
+	fOutlineView->ResizeBufferView()->UpdateMaxWidth(column->MaxWidth());
+#endif
 //	fColumnsWidth += column->Width();
 	FixScrollBar(false);
 	Invalidate();
@@ -2481,13 +2588,14 @@ TitleView::ResizeSelectedColumn(BPoint position, bool preferred)
 		destRect.OffsetBy(fSelectedColumnRect.left, 0);
 
 #if DOUBLE_BUFFERED_COLUMN_RESIZE
-		fDrawBuffer->Lock();
+		ColumnResizeBufferView* bufferView = fOutlineView->ResizeBufferView();
-		DrawTitle(fDrawBufferView, sourceRect, fSelectedColumn, false);
+		bufferView->Lock();
-		fDrawBufferView->Sync();
+		DrawTitle(bufferView, sourceRect, fSelectedColumn, false);
-		fDrawBuffer->Unlock();
+		bufferView->Sync();
+		bufferView->Unlock();
 
 		CopyBits(originalRect, movedRect);
-		DrawBitmap(fDrawBuffer, sourceRect, destRect);
+		DrawBitmap(bufferView->Bitmap(), sourceRect, destRect);
 #else
 		CopyBits(originalRect, movedRect);
 		DrawTitle(this, destRect, fSelectedColumn, false);
@@ -3113,15 +3221,7 @@ OutlineView::OutlineView(BRect rect, BList* visibleColumns, BList* sortColumns,
 	SetViewColor(B_TRANSPARENT_COLOR);
 
 #if DOUBLE_BUFFERED_COLUMN_RESIZE
-	// TODO: This needs to be smart about the size of the buffer.
+	fResizeBufferView = new ColumnResizeBufferView();
-	// Also, the buffer can be shared with the title's buffer.
-	BRect doubleBufferRect(0, 0, 600, 35);
-	fDrawBuffer = new BBitmap(doubleBufferRect, B_RGB32, true);
-	fDrawBufferView = new BView(doubleBufferRect, "double_buffer_view",
-		B_FOLLOW_ALL_SIDES, 0);
-	fDrawBuffer->Lock();
-	fDrawBuffer->AddChild(fDrawBufferView);
-	fDrawBuffer->Unlock();
 #endif
 
 	FixScrollBar(true);
@@ -3133,7 +3233,7 @@ OutlineView::OutlineView(BRect rect, BList* visibleColumns, BList* sortColumns,
 OutlineView::~OutlineView()
 {
 #if DOUBLE_BUFFERED_COLUMN_RESIZE
-	delete fDrawBuffer;
+	delete fResizeBufferView;
 #endif
 
 	Clear();
@@ -3275,15 +3375,15 @@ OutlineView::RedrawColumn(BColumn* column, float leftEdge, bool isFirstColumn)
 
 
 #if DOUBLE_BUFFERED_COLUMN_RESIZE
-			fDrawBuffer->Lock();
+			fResizeBufferView->Lock();
 
-			fDrawBufferView->SetHighColor(highColor);
+			fResizeBufferView->SetHighColor(highColor);
-			fDrawBufferView->SetLowColor(lowColor);
+			fResizeBufferView->SetLowColor(lowColor);
 
 			BFont font;
 			GetFont(&font);
-			fDrawBufferView->SetFont(&font);
+			fResizeBufferView->SetFont(&font);
-			fDrawBufferView->FillRect(sourceRect, B_SOLID_LOW);
+			fResizeBufferView->FillRect(sourceRect, B_SOLID_LOW);
 
 			if (isFirstColumn) {
 				// If this is the first column, double buffer drawing the latch
@@ -3299,7 +3399,7 @@ OutlineView::RedrawColumn(BColumn* column, float leftEdge, bool isFirstColumn)
 
 				BRect latchRect(sourceRect);
 				latchRect.right = latchRect.left + fMasterView->LatchWidth();
-				fMasterView->DrawLatch(fDrawBufferView, latchRect, pos, row);
+				fMasterView->DrawLatch(fResizeBufferView, latchRect, pos, row);
 			}
 
 			BField* field = row->GetField(column->fFieldID);
@@ -3310,33 +3410,33 @@ OutlineView::RedrawColumn(BColumn* column, float leftEdge, bool isFirstColumn)
 
 	#if CONSTRAIN_CLIPPING_REGION
 				BRegion clipRegion(fieldRect);
-				fDrawBufferView->PushState();
+				fResizeBufferView->PushState();
-				fDrawBufferView->ConstrainClippingRegion(&clipRegion);
+				fResizeBufferView->ConstrainClippingRegion(&clipRegion);
 	#endif
-				fDrawBufferView->SetHighColor(fMasterView->Color(
+				fResizeBufferView->SetHighColor(fMasterView->Color(
 					row->fNextSelected ? B_COLOR_SELECTION_TEXT
 						: B_COLOR_TEXT));
 				float baseline = floor(fieldRect.top + fh.ascent
 					+ (fieldRect.Height() + 1 - (fh.ascent+fh.descent)) / 2);
-				fDrawBufferView->MovePenTo(fieldRect.left + 8, baseline);
+				fResizeBufferView->MovePenTo(fieldRect.left + 8, baseline);
-				column->DrawField(field, fieldRect, fDrawBufferView);
+				column->DrawField(field, fieldRect, fResizeBufferView);
 	#if CONSTRAIN_CLIPPING_REGION
-				fDrawBufferView->PopState();
+				fResizeBufferView->PopState();
 	#endif
 			}
 
 			if (fFocusRow == row && !fEditMode && fMasterView->IsFocus()
 				&& Window()->IsActive()) {
-				fDrawBufferView->SetHighColor(fMasterView->Color(
+				fResizeBufferView->SetHighColor(fMasterView->Color(
 					B_COLOR_ROW_DIVIDER));
-				fDrawBufferView->StrokeRect(BRect(-1, sourceRect.top,
+				fResizeBufferView->StrokeRect(BRect(-1, sourceRect.top,
 					10000.0, sourceRect.bottom));
 			}
 
-			fDrawBufferView->Sync();
+			fResizeBufferView->Sync();
-			fDrawBuffer->Unlock();
+			fResizeBufferView->Unlock();
 			SetDrawingMode(B_OP_COPY);
-			DrawBitmap(fDrawBuffer, sourceRect, destRect);
+			DrawBitmap(fResizeBufferView->Bitmap(), sourceRect, destRect);
 
 #else
 
@@ -4013,6 +4113,17 @@ OutlineView::MessageReceived(BMessage* message)
 }
 
 
+#if DOUBLE_BUFFERED_COLUMN_RESIZE
+
+ColumnResizeBufferView*
+OutlineView::ResizeBufferView()
+{
+	return fResizeBufferView;
+}
+
+#endif
+
+
 void
 OutlineView::ChangeFocusRow(bool up, bool updateSelection,
 	bool addToCurrentSelection)
@@ -4381,6 +4492,10 @@ OutlineView::AddRow(BRow* row, int32 Index, BRow* parentRow)
 		}
 	}
 
+#ifdef DOUBLE_BUFFERED_COLUMN_RESIZE
+	ResizeBufferView()->UpdateMaxHeight(row->Height());
+#endif
+
 	if (parentRow == 0 || parentRow->fIsExpanded)
 		fItemsHeight += row->Height() + 1;