* Exposed ValidScrollOffsetFor() as public method.

* Make validating the scroll offset in SetDataRect() optional.
 * Introduced SetDataRectAndScrollOffset() to set both atomically.
   This avoids some unwanted feedback when having to set them
   both anyway, but hook methods are called and re-enter back into
   the client code.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@41179 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/apps/icon-o-matic/generic/gui/scrollview/Scrollable.cpp

@@ -1,9 +1,6 @@
 /*
- * Copyright 2006, Haiku.
+ * Copyright 2001-2009, Ingo Weinhold <[email protected]>
- * Distributed under the terms of the MIT License.
+ * All rights reserved. Distributed under the terms of the MIT license.
- *
- * Authors:
- *		Ingo Weinhold <[email protected]>
  */
 
 #include "Scrollable.h"
@@ -13,8 +10,6 @@
 
 #include "Scroller.h"
 
-using namespace std;
-
 // constructor
 Scrollable::Scrollable()
 	: fDataRect(0.0, 0.0, 0.0, 0.0),
@@ -67,7 +62,7 @@ Scrollable::ScrollSource() const
 //
 // Sets the data rect.
 void
-Scrollable::SetDataRect(BRect dataRect)
+Scrollable::SetDataRect(BRect dataRect, bool validateScrollOffset)
 {
 	if (fDataRect != dataRect && dataRect.IsValid()) {
 		BRect oldDataRect = fDataRect;
@@ -78,9 +73,11 @@ Scrollable::SetDataRect(BRect dataRect)
 		if (fScrollSource)
 			fScrollSource->DataRectChanged(oldDataRect, fDataRect);
 		// adjust the scroll offset, if necessary
-		BPoint offset = _ValidScrollOffsetFor(fScrollOffset);
+		if (validateScrollOffset) {
-		if (offset != fScrollOffset)
+			BPoint offset = ValidScrollOffsetFor(fScrollOffset);
-			SetScrollOffset(offset);
+			if (offset != fScrollOffset)
+				SetScrollOffset(offset);
+		}
 	}
 }
 
@@ -100,7 +97,7 @@ void
 Scrollable::SetScrollOffset(BPoint offset)
 {
 	// adjust the supplied offset to be valid
-	offset = _ValidScrollOffsetFor(offset);
+	offset = ValidScrollOffsetFor(offset);
 	if (fScrollOffset != offset) {
 		BPoint oldOffset = fScrollOffset;
 		fScrollOffset = offset;
@@ -121,6 +118,62 @@ Scrollable::ScrollOffset() const
 	return fScrollOffset;
 }
 
+// SetDataRect
+//
+// Sets the data rect.
+void
+Scrollable::SetDataRectAndScrollOffset(BRect dataRect, BPoint offset)
+{
+	if (fDataRect != dataRect && dataRect.IsValid()) {
+
+		BRect oldDataRect = fDataRect;
+		fDataRect = dataRect;
+		// notify ourselves
+		DataRectChanged(oldDataRect, fDataRect);
+		// notify scroller
+		if (fScrollSource) {
+			fScrollSource->SetScrollingEnabled(false);
+			fScrollSource->DataRectChanged(oldDataRect, fDataRect);
+		}
+		// adjust the scroll offset, if necessary
+		offset = ValidScrollOffsetFor(offset);
+		if (offset != fScrollOffset)
+			SetScrollOffset(offset);
+
+		if (fScrollSource)
+			fScrollSource->SetScrollingEnabled(true);
+	}
+}
+
+// ValidScrollOffsetFor
+//
+// Returns the valid scroll offset next to the supplied offset.
+BPoint
+Scrollable::ValidScrollOffsetFor(BPoint offset) const
+{
+	return ValidScrollOffsetFor(offset, fDataRect);
+}
+
+// ValidScrollOffsetFor
+//
+// Returns the valid scroll offset next to the supplied offset.
+BPoint
+Scrollable::ValidScrollOffsetFor(BPoint offset, const BRect& dataRect) const
+{
+	float maxX = max_c(dataRect.left, dataRect.right - fVisibleWidth);
+	float maxY = max_c(dataRect.top, dataRect.bottom - fVisibleHeight);
+	// adjust the offset to be valid
+	if (offset.x < dataRect.left)
+		offset.x = dataRect.left;
+	else if (offset.x > maxX)
+		offset.x = maxX;
+	if (offset.y < dataRect.top)
+		offset.y = dataRect.top;
+	else if (offset.y > maxY)
+		offset.y = maxY;
+	return offset;
+}
+
 // SetVisibleSize
 //
 // Sets the visible size.
@@ -141,7 +194,7 @@ Scrollable::SetVisibleSize(float width, float height)
 											  fVisibleWidth, fVisibleHeight);
 		}
 		// adjust the scroll offset, if necessary
-		BPoint offset = _ValidScrollOffsetFor(fScrollOffset);
+		BPoint offset = ValidScrollOffsetFor(fScrollOffset);
 		if (offset != fScrollOffset)
 			SetScrollOffset(offset);
 	}
@@ -207,23 +260,4 @@ Scrollable::ScrollSourceChanged(Scroller* /*oldSource*/,
 {
 }
 
-// _ValidScrollOffsetFor
-//
-// Returns the valid scroll offset next to the supplied offset.
-BPoint
-Scrollable::_ValidScrollOffsetFor(BPoint offset) const
-{
-	float maxX = max(fDataRect.left, fDataRect.right - fVisibleWidth);
-	float maxY = max(fDataRect.top, fDataRect.bottom - fVisibleHeight);
-	// adjust the offset to be valid
-	if (offset.x < fDataRect.left)
-		offset.x = fDataRect.left;
-	else if (offset.x > maxX)
-		offset.x = maxX;
-	if (offset.y < fDataRect.top)
-		offset.y = fDataRect.top;
-	else if (offset.y > maxY)
-		offset.y = maxY;
-	return offset;
-}
 

src/apps/icon-o-matic/generic/gui/scrollview/Scrollable.h

@@ -1,11 +1,7 @@
 /*
- * Copyright 2006, Haiku.
+ * Copyright 2001-2009, Ingo Weinhold <[email protected]>
- * Distributed under the terms of the MIT License.
+ * All rights reserved. Distributed under the terms of the MIT license.
- *
- * Authors:
- *		Ingo Weinhold <[email protected]>
  */
-
 #ifndef SCROLLABLE_H
 #define SCROLLABLE_H
 
@@ -22,12 +18,20 @@ class Scrollable {
 			void				SetScrollSource(Scroller* source);
 			Scroller*			ScrollSource() const;
 
-			void				SetDataRect(BRect dataRect);
+			void				SetDataRect(BRect dataRect,
+									bool validateScrollOffset = true);
 			BRect				DataRect() const;
 
-			void				SetScrollOffset(BPoint offset);
+	virtual	void				SetScrollOffset(BPoint offset);
 			BPoint				ScrollOffset() const;
 
+			void				SetDataRectAndScrollOffset(BRect dataRect,
+									BPoint offset);
+
+			BPoint				ValidScrollOffsetFor(BPoint offset) const;
+			BPoint				ValidScrollOffsetFor(BPoint offset,
+									const BRect& dataRect) const;
+
 			void				SetVisibleSize(float width, float height);
 			BRect				VisibleBounds() const;
 			BRect				VisibleRect() const;
@@ -50,8 +54,6 @@ protected:
 			float				fVisibleWidth;
 			float				fVisibleHeight;
 			Scroller*			fScrollSource;
-
-			BPoint				_ValidScrollOffsetFor(BPoint offset) const;
 };