GUI: Add DropdownButtonWidget and use it in the launcher for mass add

DropdownButtonWidget is a button split in two parts vertically. Clicking
the left part triggers a default action. Clicking the right part shows a
list of other actions the user can choose from.

Using this widget on the launcher lets 'Mass add' be a secondary action
of the 'Add' button, removing the necessity of pressing the shift key to
access the feature.

2 files changed, 155 insertions, 91 deletions

diff --git a/gui/widgets/popup.cpp b/gui/widgets/popup.cpp
index 970e35ab23..351d0fe559 100644
--- a/gui/widgets/popup.cpp
+++ b/gui/widgets/popup.cpp
@@ -21,7 +21,6 @@
  */
 
 #include "common/system.h"
-#include "gui/dialog.h"
 #include "gui/gui-manager.h"
 #include "gui/widgets/popup.h"
 
@@ -33,62 +32,35 @@ namespace GUI {
 // PopUpDialog
 //
 
-class PopUpDialog : public Dialog {
-protected:
-	PopUpWidget	*_popUpBoss;
-	int			_clickX, _clickY;
-	int			_selection;
-	uint32		_openTime;
-	bool		_twoColumns;
-	int			_entriesPerColumn;
-
-	int			_leftPadding;
-	int			_rightPadding;
-
-	int			_lastRead;
-
-public:
-	PopUpDialog(PopUpWidget *boss, int clickX, int clickY);
-
-	void drawDialog(DrawLayer layerToDraw) override;
-
-	void handleMouseUp(int x, int y, int button, int clickCount) override;
-	void handleMouseWheel(int x, int y, int direction) override;	// Scroll through entries with scroll wheel
-	void handleMouseMoved(int x, int y, int button) override;	// Redraw selections depending on mouse position
-	void handleMouseLeft(int button) override;
-	void handleKeyDown(Common::KeyState state) override;	// Scroll through entries with arrow keys etc.
-
-protected:
-	void drawMenuEntry(int entry, bool hilite);
-
-	int findItem(int x, int y) const;
-	void setSelection(int item);
-	bool isMouseDown();
-
-	void moveUp();
-	void moveDown();
-	void read(Common::String);
-};
-
-PopUpDialog::PopUpDialog(PopUpWidget *boss, int clickX, int clickY)
-	: Dialog(0, 0, 16, 16),
-	_popUpBoss(boss) {
+PopUpDialog::PopUpDialog(Widget *boss, const Common::String &name, int clickX, int clickY):
+		Dialog(name),
+		_boss(boss),
+		// Remember original mouse position
+		_clickX(clickX),
+		_clickY(clickY),
+		_selection(-1),
+		_initialSelection(-1),
+		_openTime(0),
+		_twoColumns(false),
+		_entriesPerColumn(1),
+		_leftPadding(0),
+		_rightPadding(0),
+		_lineHeight(kLineHeight),
+		_lastRead(-1) {
 	_backgroundType = ThemeEngine::kDialogBackgroundNone;
+	_w = _boss->getWidth();
+}
 
-	_openTime = 0;
-	_entriesPerColumn = 1;
+void PopUpDialog::open() {
+	// Time the popup was opened
+	_openTime = g_system->getMillis();
 
-	// Copy the selection index
-	_selection = _popUpBoss->_selectedItem;
+	_initialSelection = _selection;
 
 	// Calculate real popup dimensions
-	_x = _popUpBoss->getAbsX();
-	_y = _popUpBoss->getAbsY() - _popUpBoss->_selectedItem * kLineHeight;
-	_h = _popUpBoss->_entries.size() * kLineHeight + 2;
-	_w = _popUpBoss->_w - kLineHeight + 2;
+	_h = _entries.size() * _lineHeight + 2;
 
-	_leftPadding = _popUpBoss->_leftPadding;
-	_rightPadding = _popUpBoss->_rightPadding;
+	_entriesPerColumn = 1;
 
 	// Perform clipping / switch to scrolling mode if we don't fit on the screen
 	// FIXME - OSystem should send out notification messages when the screen
@@ -103,16 +75,16 @@ PopUpDialog::PopUpDialog(PopUpWidget *boss, int clickX, int clickY)
 		const int screenW = g_system->getOverlayWidth();
 
 		_twoColumns = true;
-		_entriesPerColumn = _popUpBoss->_entries.size() / 2;
+		_entriesPerColumn = _entries.size() / 2;
 
-		if (_popUpBoss->_entries.size() & 1)
+		if (_entries.size() & 1)
 			_entriesPerColumn++;
 
-		_h = _entriesPerColumn * kLineHeight + 2;
+		_h = _entriesPerColumn * _lineHeight + 2;
 		_w = 0;
 
-		for (uint i = 0; i < _popUpBoss->_entries.size(); i++) {
-			int width = g_gui.getStringWidth(_popUpBoss->_entries[i].name);
+		for (uint i = 0; i < _entries.size(); i++) {
+			int width = g_gui.getStringWidth(_entries[i]);
 
 			if (width > _w)
 				_w = width;
@@ -123,9 +95,9 @@ PopUpDialog::PopUpDialog(PopUpWidget *boss, int clickX, int clickY)
 		if (!(_w & 1))
 			_w++;
 
-		if (_popUpBoss->_selectedItem >= _entriesPerColumn) {
+		if (_selection >= _entriesPerColumn) {
 			_x -= _w / 2;
-			_y = _popUpBoss->getAbsY() - (_popUpBoss->_selectedItem - _entriesPerColumn) * kLineHeight;
+			_y = _boss->getAbsY() - (_selection - _entriesPerColumn) * _lineHeight;
 		}
 
 		if (_w >= screenW)
@@ -146,11 +118,12 @@ PopUpDialog::PopUpDialog(PopUpWidget *boss, int clickX, int clickY)
 
 	// TODO - implement scrolling if we had to move the menu, or if there are too many entries
 
-	// Remember original mouse position
-	_clickX = clickX - _x;
-	_clickY = clickY - _y;
-
 	_lastRead = -1;
+
+	Dialog::open();
+}
+
+void PopUpDialog::reflowLayout() {
 }
 
 void PopUpDialog::drawDialog(DrawLayer layerToDraw) {
@@ -163,7 +136,7 @@ void PopUpDialog::drawDialog(DrawLayer layerToDraw) {
 		g_gui.vLine(_x + _w / 2, _y, _y + _h - 2, g_gui._color);*/
 
 	// Draw the entries
-	int count = _popUpBoss->_entries.size();
+	int count = _entries.size();
 	for (int i = 0; i < count; i++) {
 		drawMenuEntry(i, i == _selection);
 	}
@@ -172,17 +145,15 @@ void PopUpDialog::drawDialog(DrawLayer layerToDraw) {
 	/*if (_twoColumns && (count & 1)) {
 		g_gui.fillRect(_x + 1 + _w / 2, _y + 1 + kLineHeight * (_entriesPerColumn - 1), _w / 2 - 1, kLineHeight, g_gui._bgcolor);
 	}*/
-
-	if (_openTime == 0) {
-		// Time the popup was opened
-		_openTime = g_system->getMillis();
-	}
 }
 
 void PopUpDialog::handleMouseUp(int x, int y, int button, int clickCount) {
+	int absX = x + getAbsX();
+	int absY = y + getAbsY();
+
 	// Mouse was released. If it wasn't moved much since the original mouse down,
 	// let the popup stay open. If it did move, assume the user made his selection.
-	int dist = (_clickX - x) * (_clickX - x) + (_clickY - y) * (_clickY - y);
+	int dist = (_clickX - absX) * (_clickX - absX) + (_clickY - absY) * (_clickY - absY);
 	if (dist > 3 * 3 || g_system->getMillis() - _openTime > 300) {
 		setResult(_selection);
 		close();
@@ -203,18 +174,18 @@ void PopUpDialog::handleMouseMoved(int x, int y, int button) {
 	// Compute over which item the mouse is...
 	int item = findItem(x, y);
 
-	if (item >= 0 && _popUpBoss->_entries[item].name.size() == 0)
+	if (item >= 0 && _entries[item].size() == 0)
 		item = -1;
 
 	if (item == -1 && !isMouseDown()) {
-		setSelection(_popUpBoss->_selectedItem);
+		setSelection(_initialSelection);
 		return;
 	}
 
 	// ...and update the selection accordingly
 	setSelection(item);
-	if (_lastRead != item && _popUpBoss->_entries.size() > 0 && item != -1) {
-		read(_popUpBoss->_entries[item].name);
+	if (_lastRead != item && _entries.size() > 0 && item != -1) {
+		read(_entries[item]);
 		_lastRead = item;
 	}
 }
@@ -261,7 +232,7 @@ void PopUpDialog::handleKeyDown(Common::KeyState state) {
 			break;
 		// fall through
 	case Common::KEYCODE_END:
-		setSelection(_popUpBoss->_entries.size()-1);
+		setSelection(_entries.size()-1);
 		break;
 
 	case Common::KEYCODE_KP2:
@@ -293,19 +264,45 @@ void PopUpDialog::handleKeyDown(Common::KeyState state) {
 	}
 }
 
+void PopUpDialog::setPosition(int x, int y) {
+	_x = x;
+	_y = y;
+}
+
+void PopUpDialog::setPadding(int left, int right) {
+	_leftPadding  = left;
+	_rightPadding = right;
+}
+
+void PopUpDialog::setLineHeight(int lineHeight) {
+	_lineHeight = lineHeight;
+}
+
+void PopUpDialog::setWidth(uint16 width) {
+	_w = width;
+}
+
+void PopUpDialog::appendEntry(const Common::String &entry) {
+	_entries.push_back(entry);
+}
+
+void PopUpDialog::clearEntries() {
+	_entries.clear();
+}
+
 int PopUpDialog::findItem(int x, int y) const {
 	if (x >= 0 && x < _w && y >= 0 && y < _h) {
 		if (_twoColumns) {
-			uint entry = (y - 2) / kLineHeight;
+			uint entry = (y - 2) / _lineHeight;
 			if (x > _w / 2) {
 				entry += _entriesPerColumn;
 
-				if (entry >= _popUpBoss->_entries.size())
+				if (entry >= _entries.size())
 					return -1;
 			}
 			return entry;
 		}
-		return (y - 2) / kLineHeight;
+		return (y - 2) / _lineHeight;
 	}
 	return -1;
 }
@@ -335,19 +332,19 @@ bool PopUpDialog::isMouseDown() {
 
 void PopUpDialog::moveUp() {
 	if (_selection < 0) {
-		setSelection(_popUpBoss->_entries.size() - 1);
+		setSelection(_entries.size() - 1);
 	} else if (_selection > 0) {
 		int item = _selection;
 		do {
 			item--;
-		} while (item >= 0 && _popUpBoss->_entries[item].name.size() == 0);
+		} while (item >= 0 && _entries[item].size() == 0);
 		if (item >= 0)
 			setSelection(item);
 	}
 }
 
 void PopUpDialog::moveDown() {
-	int lastItem = _popUpBoss->_entries.size() - 1;
+	int lastItem = _entries.size() - 1;
 
 	if (_selection < 0) {
 		setSelection(0);
@@ -355,7 +352,7 @@ void PopUpDialog::moveDown() {
 		int item = _selection;
 		do {
 			item++;
-		} while (item <= lastItem && _popUpBoss->_entries[item].name.size() == 0);
+		} while (item <= lastItem && _entries[item].size() == 0);
 		if (item <= lastItem)
 			setSelection(item);
 	}
@@ -367,34 +364,34 @@ void PopUpDialog::drawMenuEntry(int entry, bool hilite) {
 	int x, y, w;
 
 	if (_twoColumns) {
-		int n = _popUpBoss->_entries.size() / 2;
+		int n = _entries.size() / 2;
 
-		if (_popUpBoss->_entries.size() & 1)
+		if (_entries.size() & 1)
 			n++;
 
 		if (entry >= n) {
 			x = _x + 1 + _w / 2;
-			y = _y + 1 + kLineHeight * (entry - n);
+			y = _y + 1 + _lineHeight * (entry - n);
 		} else {
 			x = _x + 1;
-			y = _y + 1 + kLineHeight * entry;
+			y = _y + 1 + _lineHeight * entry;
 		}
 
 		w = _w / 2 - 1;
 	} else {
 		x = _x + 1;
-		y = _y + 1 + kLineHeight * entry;
+		y = _y + 1 + _lineHeight * entry;
 		w = _w - 2;
 	}
 
-	Common::String &name(_popUpBoss->_entries[entry].name);
+	Common::String &name(_entries[entry]);
 
 	if (name.size() == 0) {
 		// Draw a separator
-		g_gui.theme()->drawLineSeparator(Common::Rect(x, y, x + w, y + kLineHeight));
+		g_gui.theme()->drawLineSeparator(Common::Rect(x, y, x + w, y + _lineHeight));
 	} else {
 		g_gui.theme()->drawText(
-			Common::Rect(x + 1, y + 2, x + w, y + 2 + kLineHeight),
+			Common::Rect(x + 1, y + 2, x + w, y + 2 + _lineHeight),
 			name, hilite ? ThemeEngine::kStateHighlight : ThemeEngine::kStateEnabled,
 			Graphics::kTextAlignLeft, ThemeEngine::kTextInversionNone, _leftPadding
 		);
@@ -429,7 +426,17 @@ PopUpWidget::PopUpWidget(GuiObject *boss, int x, int y, int w, int h, const char
 
 void PopUpWidget::handleMouseDown(int x, int y, int button, int clickCount) {
 	if (isEnabled()) {
-		PopUpDialog popupDialog(this, x + getAbsX(), y + getAbsY());
+		PopUpDialog popupDialog(this, "", x + getAbsX(), y + getAbsY());
+		popupDialog.setPosition(getAbsX(), getAbsY() - _selectedItem * kLineHeight);
+		popupDialog.setPadding(_leftPadding, _rightPadding);
+		popupDialog.setWidth(getWidth() - kLineHeight + 2);
+
+
+		for (uint i = 0; i < _entries.size(); i++) {
+			popupDialog.appendEntry(_entries[i].name);
+		}
+		popupDialog.setSelection(_selectedItem);
+
 		int newSel = popupDialog.runModal();
 		if (newSel != -1 && _selectedItem != newSel) {
 			_selectedItem = newSel;
diff --git a/gui/widgets/popup.h b/gui/widgets/popup.h
index 3ccf8787d5..d7c218f2d3 100644
--- a/gui/widgets/popup.h
+++ b/gui/widgets/popup.h
@@ -23,6 +23,7 @@
 #ifndef GUI_WIDGETS_POPUP_H
 #define GUI_WIDGETS_POPUP_H
 
+#include "gui/dialog.h"
 #include "gui/widget.h"
 #include "common/str.h"
 #include "common/array.h"
@@ -41,7 +42,6 @@ enum {
  * is broadcast, with data being equal to the tag value of the selected entry.
  */
 class PopUpWidget : public Widget, public CommandSender {
-	friend class PopUpDialog;
 	typedef Common::String String;
 
 	struct Entry {
@@ -85,6 +85,63 @@ protected:
 	void drawWidget();
 };
 
+/**
+ * A small dialog showing a list of items and allowing the user to chose one of them
+ *
+ * Used by PopUpWidget and DropdownButtonWidget.
+ */
+class PopUpDialog : public Dialog {
+protected:
+	Widget		*_boss;
+	int			_clickX, _clickY;
+	int			_selection;
+	int			_initialSelection;
+	uint32		_openTime;
+	bool		_twoColumns;
+	int			_entriesPerColumn;
+
+	int			_leftPadding;
+	int			_rightPadding;
+	int			_lineHeight;
+
+	int			_lastRead;
+
+	typedef Common::Array<Common::String> EntryList;
+	EntryList		_entries;
+
+public:
+	PopUpDialog(Widget *boss, const Common::String &name, int clickX, int clickY);
+
+	void open() override;
+	void reflowLayout() override;
+	void drawDialog(DrawLayer layerToDraw) override;
+
+	void handleMouseUp(int x, int y, int button, int clickCount) override;
+	void handleMouseWheel(int x, int y, int direction) override;	// Scroll through entries with scroll wheel
+	void handleMouseMoved(int x, int y, int button) override;	// Redraw selections depending on mouse position
+	void handleMouseLeft(int button) override;
+	void handleKeyDown(Common::KeyState state) override;	// Scroll through entries with arrow keys etc.
+
+	void setPosition(int x, int y);
+	void setPadding(int left, int right);
+	void setLineHeight(int lineHeight);
+	void setWidth(uint16 width);
+
+	void appendEntry(const Common::String &entry);
+	void clearEntries();
+	void setSelection(int item);
+
+protected:
+	void drawMenuEntry(int entry, bool hilite);
+
+	int findItem(int x, int y) const;
+	bool isMouseDown();
+
+	void moveUp();
+	void moveDown();
+	void read(Common::String);
+};
+
 } // End of namespace GUI
 
 #endif