implemented scrollbar 'dragging' (based largely on painelf's patch)

svn-id: r4527

1 files changed, 77 insertions, 47 deletions

diff --git a/gui/ScrollBarWidget.cpp b/gui/ScrollBarWidget.cpp
index 633a01f270..028e831cad 100644
--- a/gui/ScrollBarWidget.cpp
+++ b/gui/ScrollBarWidget.cpp
@@ -32,6 +32,7 @@
  * - Allow for a horizontal scrollbar, too?
  */
 
+#define UP_DOWN_BOX_HEIGHT	10
 
 // Up arrow
 static uint32 up_arrow[8] = {
@@ -58,22 +59,24 @@ static uint32 down_arrow[8] = {
 };
 
 ScrollBarWidget::ScrollBarWidget(Dialog *boss, int x, int y, int w, int h)
-	: Widget(boss, x, y, w, h), CommandSender(boss)
+	: Widget (boss, x, y, w, h), CommandSender(boss)
 {
 	_flags = WIDGET_ENABLED | WIDGET_TRACK_MOUSE | WIDGET_CLEARBG;
 	_type = kScrollBarWidget;
-	
+
 	_part = kNoPart;
-	
+	_isDraggingSlider = false;
+
 }
 
 void ScrollBarWidget::handleClick(int x, int y, int button)
 {
 	int old_pos = _currentPos;
-	if (y <= 10) {
+
+	if (y <= UP_DOWN_BOX_HEIGHT) {
 		// Up arrow
 		_currentPos--;
-	} else if (y >= _h-10) {
+	} else if (y >= _h - UP_DOWN_BOX_HEIGHT) {
 		// Down arrow
 		_currentPos++;
 	} else if (y < _sliderPos) {
@@ -81,16 +84,13 @@ void ScrollBarWidget::handleClick(int x, int y, int button)
 	} else if (y >= _sliderPos + _sliderHeight) {
 		_currentPos += _entriesPerPage;
 	} else {
-		printf("Slider\n");
+		_isDraggingSlider = true;
+		_sliderDeltaMouseDownPos = y - _sliderPos;
 	}
-	
-	// Bound checking
-	if (_currentPos > _numEntries - _entriesPerPage)
-		_currentPos = _numEntries - _entriesPerPage;
-	else if (_currentPos < 0)
-		_currentPos = 0;
-	
-	// Redraw & notify, but only if the position really changed
+
+	// Make sure that _currentPos is still inside the bounds
+	checkbounds();
+
 	if (old_pos != _currentPos) {
 		recalc();
 		draw();
@@ -100,58 +100,88 @@ void ScrollBarWidget::handleClick(int x, int y, int button)
 
 void ScrollBarWidget::handleMouseMoved(int x, int y, int button)
 {
-	int old_part = _part;
-	if (y <= 10)				// Up arrow
-		_part = kUpArrowPart;
-	else if (y >= _h-10)		// Down arrow
-		_part = kDownArrowPart;
-	else if (y < _sliderPos)
-		_part = kPageUpPart;
-	else if (y >= _sliderPos + _sliderHeight)
-		_part = kPageDownPart;
-	else
-		_part = kSliderPart;
-	
-	if (old_part != _part)
-		draw();
+	if (button == 0)
+		_isDraggingSlider = false;
+
+	if (_isDraggingSlider) {
+		int old_pos = _currentPos;
+		_sliderPos = y - _sliderDeltaMouseDownPos;
+
+		if (_sliderPos < UP_DOWN_BOX_HEIGHT)
+			_sliderPos = UP_DOWN_BOX_HEIGHT;
+
+		if (_sliderPos > _h - UP_DOWN_BOX_HEIGHT - _sliderHeight + 1)
+			_sliderPos = _h - UP_DOWN_BOX_HEIGHT - _sliderHeight + 1;
+
+		_currentPos =
+			(_sliderPos - UP_DOWN_BOX_HEIGHT) * (_numEntries - _entriesPerPage) / (_h - _sliderHeight -
+																																						 2 * UP_DOWN_BOX_HEIGHT);
+		checkbounds();
+
+		if (_currentPos != old_pos) {
+			draw();
+			sendCommand(kSetPositionCmd, _currentPos);
+		}
+	} else {
+		int old_part = _part;
+
+		if (y <= UP_DOWN_BOX_HEIGHT)	// Up arrow
+			_part = kUpArrowPart;
+		else if (y >= _h - UP_DOWN_BOX_HEIGHT)	// Down arrow
+			_part = kDownArrowPart;
+		else if (y < _sliderPos)
+			_part = kPageUpPart;
+		else if (y >= _sliderPos + _sliderHeight)
+			_part = kPageDownPart;
+		else
+			_part = kSliderPart;
+
+		if (old_part != _part)
+			draw();
+	}
+}
+
+void ScrollBarWidget::checkbounds()
+{
+	if (_currentPos > _numEntries - _entriesPerPage)
+		_currentPos = _numEntries - _entriesPerPage;
+	else if (_currentPos < 0)
+		_currentPos = 0;
 }
 
 void ScrollBarWidget::recalc()
 {
-	_sliderHeight = (_h-20) * _entriesPerPage / _numEntries;
+	_sliderHeight = (_h - 2 * UP_DOWN_BOX_HEIGHT) * _entriesPerPage / _numEntries;
 	if (_sliderHeight < 4)
 		_sliderHeight = 4;
-	
-	_sliderPos = 10 + (_h-20-_sliderHeight+1) *_currentPos / (_numEntries - _entriesPerPage);
+
+	_sliderPos =
+		UP_DOWN_BOX_HEIGHT + (_h - 2 * UP_DOWN_BOX_HEIGHT - _sliderHeight + 1) * _currentPos / (_numEntries -
+																																														_entriesPerPage);
 	if (_sliderPos < 0)
 		_sliderPos = 0;
-	
 }
 
 
 void ScrollBarWidget::drawWidget(bool hilite)
 {
 	NewGui *gui = _boss->getGui();
-	int		bottomY = _y + _h;
-	
+	int bottomY = _y + _h;
+
 	gui->frameRect(_x, _y, _w, _h, gui->_shadowcolor);
-	
+
 	// Up arrow
-	gui->frameRect(_x, _y, _w, 10, gui->_color);
+	gui->frameRect(_x, _y, _w, UP_DOWN_BOX_HEIGHT, gui->_color);
 	gui->drawBitmap(up_arrow, _x, _y,
-				(hilite && _part == kUpArrowPart) ? gui->_textcolorhi : gui->_textcolor);
-	
+									(hilite && _part == kUpArrowPart) ? gui->_textcolorhi : gui->_textcolor);
+
 	// Down arrow
-	gui->frameRect(_x, bottomY - 9, _w, 10, gui->_color);
-	gui->drawBitmap(down_arrow, _x, bottomY - 9,
-				(hilite && _part == kDownArrowPart) ? gui->_textcolorhi : gui->_textcolor);
-	
+	gui->frameRect(_x, bottomY - UP_DOWN_BOX_HEIGHT + 1, _w, UP_DOWN_BOX_HEIGHT, gui->_color);
+	gui->drawBitmap(down_arrow, _x, bottomY - UP_DOWN_BOX_HEIGHT + 1,
+									(hilite && _part == kDownArrowPart) ? gui->_textcolorhi : gui->_textcolor);
+
 	// Slider
-	// FIXME - determine slider position and size. This depends on:
-	// * the number of entries per page
-	// * total number of entries
-	// * current scroll position (i.e. index of "first" visible entry)
 	gui->checkerRect(_x, _y + _sliderPos, _w, _sliderHeight,
-				(hilite && _part == kSliderPart) ? gui->_textcolorhi : gui->_textcolor);
+									(hilite && _part == kSliderPart) ? gui->_textcolorhi : gui->_textcolor);
 	gui->frameRect(_x, _y + _sliderPos, _w, _sliderHeight, gui->_color);
 }