Provide horizontal auto scrolling for the tree view (implemented by Harald Hvaal). As soon as KTreeView is matured enough, it can be discussed whether it should be moved to kdelibs for KDE 4.2.

CCMAIL: [email protected]

svn path=/trunk/KDE/kdebase/apps/; revision=799723

6 files changed, 287 insertions, 3 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 80353a268..6d96b7b57 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -105,6 +105,7 @@ set(dolphin_SRCS
     iconsizedialog.cpp
     iconsviewsettingspage.cpp
     infosidebarpage.cpp
+	ktreeview.cpp
     main.cpp
     metadatawidget.cpp
     metatextlabel.cpp
diff --git a/src/ktreeview.cpp b/src/ktreeview.cpp
new file mode 100644
index 000000000..7448614f9
--- /dev/null
+++ b/src/ktreeview.cpp
@@ -0,0 +1,178 @@
+/***************************************************************************
+ *   Copyright (C) 2008 by <haraldhv (at) stud.ntnu.no>                    *
+ *                                                                         *
+ *   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.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
+ ***************************************************************************/
+
+#include <KGlobalSettings>
+
+#include <QDebug>
+#include <QScrollBar>
+
+#include "ktreeview.h"
+#include "ktreeview_p.h"
+
+KTreeView::KTreeViewPrivate::KTreeViewPrivate(KTreeView *parent)
+	: parent(parent),
+	autoHorizontalScroll(true),
+	scrollTowards(0),
+	scrollPixels(5),
+	scrollDelay(50),
+	leftSideMargin(30),
+	considerDelay(500),
+	topLeftPoint(QPoint(10,10))
+{
+	Q_ASSERT(parent->verticalScrollBar());
+
+	considerDelayTimer.setInterval(considerDelay);
+
+	connect( &considerDelayTimer,
+			SIGNAL(timeout()),
+			this,
+			SLOT(considerAutoScroll())
+		   );
+
+	connect( parent->verticalScrollBar(),
+			SIGNAL(rangeChanged(int, int)),
+			&considerDelayTimer,
+			SLOT(start())
+		   );
+
+	connect( parent->verticalScrollBar(),
+			SIGNAL(valueChanged(int)),
+			&considerDelayTimer,
+			SLOT(start())
+		   );
+
+	connect( parent,
+			SIGNAL( collapsed ( const QModelIndex &)),
+			&considerDelayTimer,
+			SLOT(start())
+		   );
+
+	connect( parent,
+			SIGNAL( expanded ( const QModelIndex &)),
+			&considerDelayTimer,
+			SLOT(start())
+		   );
+
+}
+
+void KTreeView::KTreeViewPrivate::considerAutoScroll()
+{
+	qDebug() << "Considering auto scroll";
+
+	QModelIndex i = parent->indexAt(topLeftPoint);
+	int smallest = parent->width();
+
+	while (i.isValid())
+	{
+		QRect r = parent->visualRect(i);
+		if (r.top() > parent->height())
+			break;
+
+		int leftSide = r.left();
+
+		smallest = qMin(smallest, leftSide);
+		i = parent->indexBelow(i);
+	}
+
+	int currentScroll = parent->horizontalScrollBar()->value();
+
+	setScrollTowards(smallest + currentScroll - leftSideMargin);
+
+	considerDelayTimer.stop();
+
+}
+
+void KTreeView::KTreeViewPrivate::autoScrollTimeout()
+{
+
+	Q_ASSERT(parent);
+
+	QScrollBar *scrollBar = parent->horizontalScrollBar();
+	if (scrollBar == NULL)
+	{
+		qDebug() << "Warning: no scrollbar present, but told to scroll.";
+		scrollTimer.stop();
+		return;
+	}
+
+	int currentScroll = scrollBar->value();
+
+	int difference = currentScroll - scrollTowards;
+
+	if (qAbs(difference) < scrollPixels)
+	{
+		scrollBar->setValue(scrollTowards);
+		scrollTimer.stop();
+		return;
+	}
+
+	if (difference < 0)
+	{
+		scrollBar->setValue(currentScroll + scrollPixels);
+	}
+	else
+	{
+		scrollBar->setValue(currentScroll - scrollPixels);
+	}
+}
+
+void KTreeView::KTreeViewPrivate::setScrollTowards( int scrollTowards )
+{
+	if (scrollTowards < 0)
+		scrollTowards = 0;
+	this->scrollTowards = scrollTowards;
+	scrollTimer.start(scrollDelay);
+}
+
+//************************************************
+
+KTreeView::KTreeView(QWidget *parent)
+	: QTreeView(parent)
+	, d(new KTreeViewPrivate(this))
+{
+	/* The graphicEffectsLevel was not available in the 4.0.3 version of
+	 * the libs I was compiling with, so this is left out for now and
+	 * enabled by default...
+	 */
+	//if (KGlobalSettings::graphicEffectsLevel() >=
+			//KGlobalSettings::SimpleAnimationEffects)
+	//{
+		setAutoHorizontalScroll(true);
+	//}
+		connect(
+				&d->scrollTimer,
+				SIGNAL(timeout()),
+				d,
+				SLOT(autoScrollTimeout())
+			   );
+
+}
+
+void KTreeView::setAutoHorizontalScroll(bool value)
+{
+	d->autoHorizontalScroll = value;
+}
+
+bool KTreeView::autoHorizontalScroll( void )
+{
+	return d->autoHorizontalScroll;
+}
+
+#include "ktreeview.moc"
+#include "ktreeview_p.moc"
diff --git a/src/ktreeview.h b/src/ktreeview.h
new file mode 100644
index 000000000..93b4b892e
--- /dev/null
+++ b/src/ktreeview.h
@@ -0,0 +1,42 @@
+/***************************************************************************
+ *   Copyright (C) 2008 by <haraldhv (at) stud.ntnu.no>                    *
+ *                                                                         *
+ *   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.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
+ ***************************************************************************/
+
+#ifndef _KTREEVIEW_H_
+#define _KTREEVIEW_H_
+
+#include <QTreeView>
+
+class KTreeView : public QTreeView
+{
+
+	Q_OBJECT
+
+	public:
+		KTreeView(QWidget *parent = NULL);
+
+		void setAutoHorizontalScroll(bool value);
+		bool autoHorizontalScroll( void );
+
+	private:
+		class KTreeViewPrivate;
+		KTreeViewPrivate *d;
+
+};
+
+#endif /* ifndef _KTREEVIEW_H_ */
diff --git a/src/ktreeview_p.h b/src/ktreeview_p.h
new file mode 100644
index 000000000..eb71999f7
--- /dev/null
+++ b/src/ktreeview_p.h
@@ -0,0 +1,63 @@
+/***************************************************************************
+ *   Copyright (C) 2008 by <haraldhv (at) stud.ntnu.no>                    *
+ *                                                                         *
+ *   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.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
+ ***************************************************************************/
+
+#ifndef _KTREEVIEW_P_H_
+#define _KTREEVIEW_P_H_
+
+#include <QTimer>
+#include <QObject>
+
+#include "ktreeview.h"
+
+class KTreeView::KTreeViewPrivate : public QObject
+{
+	Q_OBJECT
+
+
+
+	public Q_SLOTS:
+		void autoScrollTimeout();
+		void considerAutoScroll();
+
+	public:
+
+		KTreeViewPrivate(KTreeView *parent);
+		//~KTreeViewPrivate();
+		KTreeView *parent;
+
+		//Function for start scrolling towards a certain position
+		void setScrollTowards( int scrollTowards );
+
+		//Privates for doing the scrolling
+		QTimer scrollTimer;
+		QTimer considerDelayTimer;
+		bool autoHorizontalScroll;
+		int scrollTowards;
+
+		//Constants
+		const int scrollPixels;
+		const int scrollDelay;
+		const int leftSideMargin;
+		const int considerDelay;
+		const QPoint topLeftPoint;
+
+
+};
+
+#endif /* ifndef _KTREEVIEW_P_H_ */
diff --git a/src/sidebartreeview.cpp b/src/sidebartreeview.cpp
index f14ddbacb..efe406a0e 100644
--- a/src/sidebartreeview.cpp
+++ b/src/sidebartreeview.cpp
@@ -30,7 +30,7 @@
 #include <QScrollBar>
 
 SidebarTreeView::SidebarTreeView(QWidget* parent) :
-    QTreeView(parent)
+    KTreeView(parent)
 {
     setAcceptDrops(true);
     setUniformRowHeights(true);
diff --git a/src/sidebartreeview.h b/src/sidebartreeview.h
index a181290f2..f692be3a2 100644
--- a/src/sidebartreeview.h
+++ b/src/sidebartreeview.h
@@ -21,14 +21,14 @@
 #define SIDEBARTREEVIEW_H
 
 #include <kurl.h>
-#include <QtGui/QTreeView>
+#include <ktreeview.h>
 
 /**
  * @brief Tree view widget which is used for the sidebar panel.
  *
  * @see TreeViewSidebarPage
  */
-class SidebarTreeView : public QTreeView
+class SidebarTreeView : public KTreeView
 {
     Q_OBJECT