1 files changed, 179 insertions, 0 deletions
diff --git a/src/gvcore/dragpixmapgenerator.h b/src/gvcore/dragpixmapgenerator.h
new file mode 100644
index 0000000..7699eed
--- /dev/null
+++ b/src/gvcore/dragpixmapgenerator.h
@@ -0,0 +1,179 @@
+// vim: set tabstop=4 shiftwidth=4 noexpandtab:
+/*
+Gwenview - A simple image viewer for KDE
+Copyright 2000-2004 Aurélien Gâteau
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+#ifndef DRAGPIXMAPGENERATOR_H
+#define DRAGPIXMAPGENERATOR_H
+
+// Qt
+#include <qapplication.h>
+#include <qpixmap.h>
+#include <qtooltip.h>
+#include <qvaluelist.h>
+#include <qvaluevector.h>
+
+// KDE
+#include <klocale.h>
+
+namespace Gwenview {
+
+
+template <class T>
+class DragPixmapGenerator;
+
+
+template <class T>
+class DragPixmapItemDrawer {
+public:
+	DragPixmapItemDrawer()
+	: mGenerator(0) {}
+	virtual ~DragPixmapItemDrawer() {}
+	virtual void setGenerator(DragPixmapGenerator<T>* generator) {
+		mGenerator = generator;
+	}
+	virtual QSize itemSize(T)=0;
+	virtual void drawItem(QPainter*, int left, int top, T)=0;
+	virtual int spacing() const { 
+		return 0;
+	}
+
+protected:
+	DragPixmapGenerator<T>* mGenerator;
+};
+
+
+QPixmap dragPixmapGeneratorHelper(QValueVector<QPixmap> pixmapVector);
+
+
+template <class T>
+class DragPixmapGenerator {
+public:
+	/** Offset between cursor and dragged images */
+	static const uint DRAG_OFFSET=16;
+
+
+	/** Maximum width of an item painted by DragPixmapItemDrawer */
+	static const int ITEM_MAX_WIDTH=128;
+
+	static const int MAX_HEIGHT=200;
+
+	static const int DRAG_MARGIN=4;
+
+
+	DragPixmapGenerator()
+	: mPixmapWidth(0) {}
+
+
+    void addItem(const T& item) {
+		mItemList << item;
+	}
+
+
+	int maxWidth() const {
+		return ITEM_MAX_WIDTH;
+	}
+
+
+	/**
+	 * Returns the width of the generated pixmap, not including the margin.
+	 * To be used by DragPixmapItemDrawer<T>::drawItem. Should not be used
+	 * anywhere else since this value is initialized in generate().
+	 */
+	int pixmapWidth() const {
+		return mPixmapWidth;
+	}
+
+    void setItemDrawer(DragPixmapItemDrawer<T>* drawer) {
+		mItemDrawer = drawer;
+		drawer->setGenerator(this);
+	}
+
+    QPixmap generate() {
+		int width = 0, height = 0;
+		int dragCount = 0;
+		int spacing = mItemDrawer->spacing();
+		bool listCropped;
+		QString bottomText;
+		QFontMetrics fm = QApplication::fontMetrics();
+
+		// Compute pixmap size and update dragCount
+		QValueListIterator<T> it = mItemList.begin();
+		QValueListIterator<T> end = mItemList.end();
+		height = -spacing;
+		for (; it!= end && height < MAX_HEIGHT; ++dragCount, ++it) {
+			QSize itemSize = mItemDrawer->itemSize(*it);
+			Q_ASSERT(itemSize.width() <= ITEM_MAX_WIDTH);
+			
+			width = QMAX(width, itemSize.width());
+			height += itemSize.height() + spacing;
+		}
+
+		listCropped = it != end;
+		if (listCropped) {
+			// If list has been cropped, leave space for item count text
+			height += fm.height();
+			bottomText = i18n("%1 items").arg(mItemList.count());
+			width = QMAX(width, fm.width("... " + bottomText));
+		}
+		
+		mPixmapWidth = width;
+
+		// Init pixmap
+		QPixmap pixmap(width + 2*DRAG_MARGIN, height + 2*DRAG_MARGIN);
+		QColorGroup cg = QToolTip::palette().active();
+
+		pixmap.fill(cg.base());
+		QPainter painter(&pixmap);
+		
+		// Draw border
+		painter.setPen(cg.dark());
+		painter.drawRect(pixmap.rect());
+		
+		// Draw items
+		it = mItemList.begin();
+		height = DRAG_MARGIN;
+		for (int pos=0; pos < dragCount; ++pos, ++it) {
+			mItemDrawer->drawItem(&painter, DRAG_MARGIN, height, *it);
+			height += mItemDrawer->itemSize(*it).height() + spacing;
+		}
+
+		// Draw text if necessary
+		if (listCropped) {
+			int posY= height + fm.ascent();
+			painter.drawText(DRAG_MARGIN, posY, "...");
+			int offset = width - fm.width(bottomText);
+			painter.drawText(DRAG_MARGIN + offset, posY, bottomText);
+		}
+		painter.end();
+
+		return pixmap;
+	}
+
+
+private:
+	QValueList<T> mItemList;
+	DragPixmapItemDrawer<T>* mItemDrawer;
+	int mPixmapWidth;
+};
+
+
+} // namespace
+
+
+#endif /* DRAGPIXMAPGENERATOR_H */