path: root/indra/llui/lltoolbar.cpp

/** 
 * @file lltoolbar.cpp
 * @author Richard Nelson
 * @brief User customizable toolbar class
 *
 * $LicenseInfo:firstyear=2011&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2011, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "linden_common.h"

#include <boost/foreach.hpp>
#include "lltoolbar.h"

#include "llcommandmanager.h"
#include "llmenugl.h"
#include "lltrans.h"

// uncomment this and remove the one in llui.cpp when there is an external reference to this translation unit
// thanks, MSVC!
//static LLDefaultChildRegistry::Register<LLToolBar> r1("toolbar");

namespace LLToolBarEnums
{
	LLLayoutStack::ELayoutOrientation getOrientation(SideType sideType)
	{
		LLLayoutStack::ELayoutOrientation orientation = LLLayoutStack::HORIZONTAL;

		if ((sideType == SIDE_LEFT) || (sideType == SIDE_RIGHT))
		{
			orientation = LLLayoutStack::VERTICAL;
		}

		return orientation;
	}
}

using namespace LLToolBarEnums;


namespace LLInitParam
{
	void TypeValues<ButtonType>::declareValues()
	{
		declare("icons_with_text",	BTNTYPE_ICONS_WITH_TEXT);
		declare("icons_only",		BTNTYPE_ICONS_ONLY);
	}

	void TypeValues<SideType>::declareValues()
	{
		declare("bottom",	SIDE_BOTTOM);
		declare("left",		SIDE_LEFT);
		declare("right",	SIDE_RIGHT);
		declare("top",		SIDE_TOP);
	}
}

LLToolBar::Params::Params()
:	button_display_mode("button_display_mode"),
	commands("command"),
	side("side", SIDE_TOP),
	button_icon("button_icon"),
	button_icon_and_text("button_icon_and_text"),
	read_only("read_only", false),
	wrap("wrap", true),
	pad_left("pad_left"),
	pad_top("pad_top"),
	pad_right("pad_right"),
	pad_bottom("pad_bottom"),
	pad_between("pad_between"),
	button_panel("button_panel")
{}

LLToolBar::LLToolBar(const LLToolBar::Params& p)
:	LLUICtrl(p),
	mReadOnly(p.read_only),
	mButtonType(p.button_display_mode),
	mSideType(p.side),
	mWrap(p.wrap),
	mNeedsLayout(false),
	mButtonPanel(NULL),
	mCenteringStack(NULL),
	mPadLeft(p.pad_left),
	mPadRight(p.pad_right),
	mPadTop(p.pad_top),
	mPadBottom(p.pad_bottom),
	mPadBetween(p.pad_between),
	mPopupMenuHandle(),
	mStartDragItemCallback(NULL),
	mHandleDragItemCallback(NULL),
	mHandleDropCallback(NULL),
	mDragAndDropTarget(false)
{
	mButtonParams[LLToolBarEnums::BTNTYPE_ICONS_WITH_TEXT] = p.button_icon_and_text;
	mButtonParams[LLToolBarEnums::BTNTYPE_ICONS_ONLY] = p.button_icon;
}

LLToolBar::~LLToolBar()
{
	delete mPopupMenuHandle.get();
}

void LLToolBar::createContextMenu()
{
	if (!mPopupMenuHandle.get())
	{
		// Setup bindings specific to this instance for the context menu options

		LLUICtrl::CommitCallbackRegistry::ScopedRegistrar commit_reg;
		commit_reg.add("Toolbars.EnableSetting", boost::bind(&LLToolBar::onSettingEnable, this, _2));

		LLUICtrl::EnableCallbackRegistry::ScopedRegistrar enable_reg;
		enable_reg.add("Toolbars.CheckSetting", boost::bind(&LLToolBar::isSettingChecked, this, _2));

		// Create the context menu
		LLContextMenu* menu = LLUICtrlFactory::instance().createFromFile<LLContextMenu>("menu_toolbars.xml", LLMenuGL::sMenuContainer, LLMenuHolderGL::child_registry_t::instance());

		if (menu)
		{
			menu->setBackgroundColor(LLUIColorTable::instance().getColor("MenuPopupBgColor"));

			mPopupMenuHandle = menu->getHandle();
		}
		else
		{
			llwarns << "Unable to load toolbars context menu." << llendl;
		}
	}
}

void LLToolBar::initFromParams(const LLToolBar::Params& p)
{
	// Initialize the base object
	LLUICtrl::initFromParams(p);
	
	LLLayoutStack::ELayoutOrientation orientation = getOrientation(p.side);

	LLLayoutStack::Params centering_stack_p;
	centering_stack_p.name = "centering_stack";
	centering_stack_p.rect = getLocalRect();
	centering_stack_p.follows.flags = FOLLOWS_ALL;
	centering_stack_p.orientation = orientation;
	centering_stack_p.mouse_opaque = false;

	mCenteringStack = LLUICtrlFactory::create<LLLayoutStack>(centering_stack_p);
	addChild(mCenteringStack);
	
	LLLayoutPanel::Params border_panel_p;
	border_panel_p.name = "border_panel";
	border_panel_p.rect = getLocalRect();
	border_panel_p.auto_resize = true;
	border_panel_p.user_resize = false;
	border_panel_p.mouse_opaque = false;
	
	mCenteringStack->addChild(LLUICtrlFactory::create<LLLayoutPanel>(border_panel_p));

	LLLayoutPanel::Params center_panel_p;
	center_panel_p.name = "center_panel";
	center_panel_p.rect = getLocalRect();
	center_panel_p.auto_resize = false;
	center_panel_p.user_resize = false;
	center_panel_p.mouse_opaque = false;
	LLLayoutPanel* center_panel = LLUICtrlFactory::create<LLLayoutPanel>(center_panel_p);
	mCenteringStack->addChild(center_panel);

	LLPanel::Params button_panel_p(p.button_panel);
	button_panel_p.rect = center_panel->getLocalRect();
		button_panel_p.follows.flags = FOLLOWS_BOTTOM|FOLLOWS_LEFT;
	mButtonPanel = LLUICtrlFactory::create<LLPanel>(button_panel_p);
	center_panel->addChild(mButtonPanel);
	
	mCenteringStack->addChild(LLUICtrlFactory::create<LLLayoutPanel>(border_panel_p));

	BOOST_FOREACH(LLCommandId::Params params, p.commands)
	{
		addCommand(params);
	}

	mNeedsLayout = true;
}

bool LLToolBar::addCommand(const LLCommandId& commandId, int rank)
{
	LLCommand * command = LLCommandManager::instance().getCommand(commandId);
	if (!command) return false;

	// Create the button and do the things that don't need ordering
	LLToolBarButton* button = createButton(commandId);
	mButtonPanel->addChild(button);
	mButtonMap.insert(std::make_pair(commandId, button));

	// Insert the command and button in the right place in their respective lists
	if ((rank >= mButtonCommands.size()) || (rank < 0))
	{
		// In that case, back load
		mButtonCommands.push_back(commandId);
		mButtons.push_back(button);
	}
	else 
	{
		// Insert in place: iterate to the right spot...
		std::list<LLToolBarButton*>::iterator it_button = mButtons.begin();
		command_id_list_t::iterator it_command = mButtonCommands.begin();
		while (rank > 0)
		{
			++it_button;
			++it_command;
			rank--;
		}
		// ...then insert
		mButtonCommands.insert(it_command,commandId);
		mButtons.insert(it_button,button);
	}

	mNeedsLayout = true;

	return true;
}

bool LLToolBar::removeCommand(const LLCommandId& commandId)
{
	if (!hasCommand(commandId)) return false;
	
	// First erase the map record
	command_id_map::iterator it = mButtonMap.find(commandId);
	mButtonMap.erase(it);
	
	// Now iterate on the commands and buttons to identify the relevant records
	std::list<LLToolBarButton*>::iterator it_button = mButtons.begin();
	command_id_list_t::iterator it_command = mButtonCommands.begin();
	while (*it_command != commandId)
	{
		++it_button;
		++it_command;
	}
	
	// Delete the button and erase the command and button records
	delete (*it_button);
	mButtonCommands.erase(it_command);
	mButtons.erase(it_button);

	mNeedsLayout = true;
	
	return true;
}

void LLToolBar::clearCommandsList()
{
	// Clears the commands list
	mButtonCommands.clear();
	// This will clear the buttons
	createButtons();
}

bool LLToolBar::hasCommand(const LLCommandId& commandId) const
{
	if (commandId != LLCommandId::null)
	{
		command_id_map::const_iterator it = mButtonMap.find(commandId);
		return (it != mButtonMap.end());
	}

	return false;
}

bool LLToolBar::enableCommand(const LLCommandId& commandId, bool enabled)
{
	LLButton * command_button = NULL;
	
	if (commandId != LLCommandId::null)
	{
		command_id_map::iterator it = mButtonMap.find(commandId);
		if (it != mButtonMap.end())
		{
			it->second->setEnabled(enabled);
		}
	}

	return (command_button != NULL);
}

BOOL LLToolBar::handleRightMouseDown(S32 x, S32 y, MASK mask)
{
	LLRect button_panel_rect;
	mButtonPanel->localRectToOtherView(mButtonPanel->getLocalRect(), &button_panel_rect, this);
	BOOL handle_it_here = !mReadOnly && button_panel_rect.pointInRect(x, y);

	if (handle_it_here)
	{
		createContextMenu();

		LLContextMenu * menu = (LLContextMenu *) mPopupMenuHandle.get();

		if (menu)
		{
			menu->show(x, y);

			LLMenuGL::showPopup(this, menu, x, y);
		}
	}

	return handle_it_here;
}

BOOL LLToolBar::isSettingChecked(const LLSD& userdata)
{
	BOOL retval = FALSE;

	const std::string setting_name = userdata.asString();

	if (setting_name == "icons_with_text")
	{
		retval = (mButtonType == BTNTYPE_ICONS_WITH_TEXT);
	}
	else if (setting_name == "icons_only")
	{
		retval = (mButtonType == BTNTYPE_ICONS_ONLY);
	}

	return retval;
}

void LLToolBar::onSettingEnable(const LLSD& userdata)
{
	llassert(!mReadOnly);

	const std::string setting_name = userdata.asString();

	if (setting_name == "icons_with_text")
	{
		setButtonType(BTNTYPE_ICONS_WITH_TEXT);
	}
	else if (setting_name == "icons_only")
	{
		setButtonType(BTNTYPE_ICONS_ONLY);
	}
}

void LLToolBar::setButtonType(LLToolBarEnums::ButtonType button_type)
{
	bool regenerate_buttons = (mButtonType != button_type);
	
	mButtonType = button_type;

	if (regenerate_buttons)
	{
		createButtons();
	}
}

void LLToolBar::resizeButtonsInRow(std::vector<LLToolBarButton*>& buttons_in_row, S32 max_row_girth)
{
	// make buttons in current row all same girth
	BOOST_FOREACH(LLToolBarButton* button, buttons_in_row)
	{
		if (getOrientation(mSideType) == LLLayoutStack::HORIZONTAL)
		{
			button->reshape(button->mWidthRange.clamp(button->getRect().getWidth()), max_row_girth);
		}
		else // VERTICAL
		{
			button->reshape(max_row_girth, button->getRect().getHeight());
		}
	}
}

int LLToolBar::getRankFromPosition(S32 x, S32 y)
{
	int rank = 0;

	LLLayoutStack::ELayoutOrientation orientation = getOrientation(mSideType);
	S32 button_panel_x = 0;
	S32 button_panel_y = 0;
	localPointToOtherView(x, y, &button_panel_x, &button_panel_y, mButtonPanel);
	
	//llinfos << "Merov debug : rank compute: orientation = " << orientation << ", x = " << button_panel_x << ", y = " << button_panel_y << llendl;

	// Simply compare the passed coord with the buttons outbound box
	std::list<LLToolBarButton*>::iterator it_button = mButtons.begin();
	std::list<LLToolBarButton*>::iterator end_button = mButtons.end();
	while (it_button != end_button)
	{
		LLRect button_rect = (*it_button)->getRect();
		//llinfos << "Merov debug : rank compute: rect = " << button_rect.mLeft << ", " << button_rect.mTop << ", " << button_rect.mRight << ", " << button_rect.mBottom << llendl;
		if (((orientation == LLLayoutStack::HORIZONTAL) && (button_rect.mRight  > button_panel_x)) ||
			((orientation == LLLayoutStack::VERTICAL)   && (button_rect.mBottom < button_panel_y))    )
		{
			break;
		}
		rank++;
		++it_button;
	}
	//llinfos << "Merov debug : rank = " << rank << llendl;

	return rank;
}

void LLToolBar::updateLayoutAsNeeded()
{
	if (!mNeedsLayout) return;

	LLLayoutStack::ELayoutOrientation orientation = getOrientation(mSideType);
	
	// our terminology for orientation-agnostic layout is such that
	// length refers to a distance in the direction we stack the buttons 
	// and girth refers to a distance in the direction buttons wrap
	S32 max_row_girth = 0;
	S32 max_row_length = 0;

	S32 max_length;
	S32 max_total_girth;
	S32 cur_start;
	S32 cur_row ;
	S32 row_pad_start;
	S32 row_pad_end;
	S32 girth_pad_end;
	S32 row_running_length;

	if (orientation == LLLayoutStack::HORIZONTAL)
	{
		max_length = getRect().getWidth() - mPadLeft - mPadRight;
		max_total_girth = getRect().getHeight() - mPadTop - mPadBottom;
		row_pad_start = mPadLeft;
		row_pad_end = mPadRight;
		cur_row = mPadTop;
		girth_pad_end = mPadBottom;
	}
	else // VERTICAL
	{
		max_length = getRect().getHeight() - mPadTop - mPadBottom;
		max_total_girth = getRect().getWidth() - mPadLeft - mPadRight;
		row_pad_start = mPadTop;
		row_pad_end = mPadBottom;
		cur_row = mPadLeft;
		girth_pad_end = mPadRight;
	}
	
	row_running_length = row_pad_start;
	cur_start = row_pad_start;


	LLRect panel_rect = mButtonPanel->getLocalRect();

	std::vector<LLToolBarButton*> buttons_in_row;

	BOOST_FOREACH(LLToolBarButton* button, mButtons)
	{
		button->reshape(button->mWidthRange.getMin(), button->mDesiredHeight);
		button->autoResize();

		S32 button_clamped_width = button->mWidthRange.clamp(button->getRect().getWidth());
		S32 button_length = (orientation == LLLayoutStack::HORIZONTAL)
							? button_clamped_width
							: button->getRect().getHeight();
		S32 button_girth = (orientation == LLLayoutStack::HORIZONTAL)
							? button->getRect().getHeight()
							: button_clamped_width;
		
		// wrap if needed
		if (mWrap
			&& row_running_length + button_length > max_length	// out of room...
			&& cur_start != row_pad_start)						// ...and not first button in row
		{
			if (orientation == LLLayoutStack::VERTICAL)
			{	// row girth (width in this case) is clamped to allowable button widths
				max_row_girth = button->mWidthRange.clamp(max_row_girth);
			}

			// make buttons in current row all same girth
			resizeButtonsInRow(buttons_in_row, max_row_girth);
			buttons_in_row.clear();

			max_row_length = llmax(max_row_length, row_running_length);
			row_running_length = row_pad_start;
			cur_start = row_pad_start;
			cur_row += max_row_girth + mPadBetween;
			max_row_girth = 0;
		}

		LLRect button_rect;
		if (orientation == LLLayoutStack::HORIZONTAL)
		{
			button_rect.setLeftTopAndSize(cur_start, panel_rect.mTop - cur_row, button_clamped_width, button->getRect().getHeight());
		}
		else // VERTICAL
		{
			button_rect.setLeftTopAndSize(cur_row, panel_rect.mTop - cur_start, button_clamped_width, button->getRect().getHeight());
		}
		button->setShape(button_rect);

		buttons_in_row.push_back(button);

		row_running_length += button_length + mPadBetween;
		cur_start = row_running_length;
		max_row_girth = llmax(button_girth, max_row_girth);
	}

	// final resizing in "girth" direction
	S32 total_girth =	cur_row				// current row position...
						+ max_row_girth		// ...incremented by size of final row...
						+ girth_pad_end;	// ...plus padding reserved on end
	max_row_length = llmax(max_row_length, row_running_length - mPadBetween + row_pad_end);

	resizeButtonsInRow(buttons_in_row, max_row_girth);

	// grow and optionally shift toolbar to accommodate buttons
	if (orientation == LLLayoutStack::HORIZONTAL)
	{
		if (mSideType == SIDE_TOP)
		{ // shift down to maintain top edge
			translate(0, getRect().getHeight() - total_girth);
		}

		reshape(getRect().getWidth(), total_girth);
		mButtonPanel->reshape(max_row_length, total_girth);
	}
	else // VERTICAL
	{
		if (mSideType == SIDE_RIGHT)
		{ // shift left to maintain right edge
			translate(getRect().getWidth() - total_girth, 0);
		}
		
		reshape(total_girth, getRect().getHeight());
		mButtonPanel->reshape(total_girth, max_row_length);
	}

	// make parent fit button panel
	mButtonPanel->getParent()->setShape(mButtonPanel->getLocalRect());

	// re-center toolbar buttons
	mCenteringStack->updateLayout();

	// don't clear flag until after we've resized ourselves, to avoid laying out every frame
	mNeedsLayout = false;
}


void LLToolBar::draw()
{
	if (mButtons.empty())
	{
		mButtonPanel->setVisible(FALSE);
		mButtonPanel->setMouseOpaque(FALSE);
	}
	else
	{
		mButtonPanel->setVisible(TRUE);
		mButtonPanel->setMouseOpaque(TRUE);
	}

	// Update enable/disable state and highlight state for editable toolbars
	if (!mReadOnly)
	{
		for (toolbar_button_list::iterator btn_it = mButtons.begin(); btn_it != mButtons.end(); ++btn_it)
		{
			LLToolBarButton* btn = *btn_it;
			LLCommand* command = LLCommandManager::instance().getCommand(btn->mId);

			if (command && btn->mIsEnabledSignal)
			{
				const bool button_command_enabled = (*btn->mIsEnabledSignal)(btn, command->isEnabledParameters());
				btn->setEnabled(button_command_enabled);
			}

			if (command && btn->mIsRunningSignal)
			{
				const bool button_command_running = (*btn->mIsRunningSignal)(btn, command->isRunningParameters());
				btn->setToggleState(button_command_running);
			}
		}
	}

	updateLayoutAsNeeded();
	// rect may have shifted during layout
	LLUI::popMatrix();
	LLUI::pushMatrix();
	LLUI::translate((F32)getRect().mLeft, (F32)getRect().mBottom, 0.f);

	LLUICtrl::draw();
}

void LLToolBar::reshape(S32 width, S32 height, BOOL called_from_parent)
{
	LLUICtrl::reshape(width, height, called_from_parent);
	mNeedsLayout = true;
}

void LLToolBar::createButtons()
{
	BOOST_FOREACH(LLToolBarButton* button, mButtons)
	{
		delete button;
	}
	mButtons.clear();
	mButtonMap.clear();
	
	BOOST_FOREACH(LLCommandId& command_id, mButtonCommands)
	{
		LLToolBarButton* button = createButton(command_id);
		mButtons.push_back(button);
		mButtonPanel->addChild(button);
		mButtonMap.insert(std::make_pair(command_id, button));
	}
	mNeedsLayout = true;
}

LLToolBarButton* LLToolBar::createButton(const LLCommandId& id)
{
	LLCommand* commandp = LLCommandManager::instance().getCommand(id);
	if (!commandp) return NULL;

	std::string label = LLTrans::getString(commandp->labelRef());
	std::string tooltip = label + "\n" + LLTrans::getString(commandp->tooltipRef());

	LLToolBarButton::Params button_p;
	button_p.name = id.name();
	button_p.label = label;
	button_p.tool_tip = tooltip;
	button_p.image_overlay = LLUI::getUIImage(commandp->icon());
	button_p.overwriteFrom(mButtonParams[mButtonType]);
	LLToolBarButton* button = LLUICtrlFactory::create<LLToolBarButton>(button_p);

	if (!mReadOnly)
	{
		LLUICtrl::CommitCallbackParam cbParam;
		cbParam.function_name = commandp->executeFunctionName();
		cbParam.parameter = commandp->executeParameters();

		button->setCommitCallback(cbParam);

		const std::string& isEnabledFunction = commandp->isEnabledFunctionName();
		if (isEnabledFunction.length() > 0)
		{
			LLUICtrl::EnableCallbackParam isEnabledParam;
			isEnabledParam.function_name = isEnabledFunction;
			isEnabledParam.parameter = commandp->isEnabledParameters();
			enable_signal_t::slot_type isEnabledCB = initEnableCallback(isEnabledParam);

			if (NULL == button->mIsEnabledSignal)
			{
				button->mIsEnabledSignal = new enable_signal_t();
			}

			button->mIsEnabledSignal->connect(isEnabledCB);
		}

		const std::string& isRunningFunction = commandp->isRunningFunctionName();
		if (isRunningFunction.length() > 0)
		{
			LLUICtrl::EnableCallbackParam isRunningParam;
			isRunningParam.function_name = isRunningFunction;
			isRunningParam.parameter = commandp->isRunningParameters();
			enable_signal_t::slot_type isRunningCB = initEnableCallback(isRunningParam);

			if (NULL == button->mIsRunningSignal)
			{
				button->mIsRunningSignal = new enable_signal_t();
			}

			button->mIsRunningSignal->connect(isRunningCB);
		}
	}

	// Drag and drop behavior must work also if provided in the Toybox and, potentially, any read-only toolbar
	button->setStartDragCallback(mStartDragItemCallback);
	button->setHandleDragCallback(mHandleDragItemCallback);

	button->setCommandId(id);

	return button;
}

BOOL LLToolBar::handleDragAndDrop(S32 x, S32 y, MASK mask, BOOL drop,
										EDragAndDropType cargo_type,
										void* cargo_data,
										EAcceptance* accept,
										std::string& tooltip_msg)
{
	//llinfos << "Merov debug : handleDragAndDrop. drop = " << drop << ", x = " << x << ", y = " << y << llendl;
	// If we have a drop callback, that means that we can handle the drop
	BOOL handled = (mHandleDropCallback ? TRUE : FALSE);
	
	// if drop is set, it's time to call the callback to get the operation done
	if (handled && drop)
	{
		handled = mHandleDropCallback(cargo_data, x, y ,this);
	}
	
	// We accept only single tool drop on toolbars
	*accept = (handled ? ACCEPT_YES_SINGLE : ACCEPT_NO);
	
	// We'll use that flag to change the visual aspect of the toolbar target on draw()
	mDragAndDropTarget = handled;
	
	return handled;
}

LLToolBarButton::LLToolBarButton(const Params& p) 
:	LLButton(p),
	mMouseDownX(0),
	mMouseDownY(0),
	mWidthRange(p.button_width),
	mDesiredHeight(p.desired_height),
	mId(""),
	mIsEnabledSignal(NULL),
	mIsRunningSignal(NULL),
	mIsStartingSignal(NULL),
	mIsDragged(false),
	mStartDragItemCallback(NULL),
	mHandleDragItemCallback(NULL)
{
	mButtonFlashRate = 0.0;
	mButtonFlashCount = 0;
}

LLToolBarButton::~LLToolBarButton()
{
	delete mIsEnabledSignal;
	delete mIsRunningSignal;
	delete mIsStartingSignal;
}

BOOL LLToolBarButton::handleMouseDown(S32 x, S32 y, MASK mask)
{
	mMouseDownX = x;
	mMouseDownY = y;
	return LLButton::handleMouseDown(x, y, mask);
}

BOOL LLToolBarButton::handleHover(S32 x, S32 y, MASK mask)
{
//	llinfos << "Merov debug: handleHover, x = " << x << ", y = " << y << ", mouse = " << hasMouseCapture() << llendl;
	BOOL handled = FALSE;
		
	S32 mouse_distance_squared = (x - mMouseDownX) * (x - mMouseDownX) + (y - mMouseDownY) * (y - mMouseDownY);
	S32 drag_threshold = LLUI::sSettingGroups["config"]->getS32("DragAndDropDistanceThreshold");
	if (mouse_distance_squared > drag_threshold * drag_threshold
		&& hasMouseCapture() && 
		mStartDragItemCallback && mHandleDragItemCallback)
	{
		if (!mIsDragged)
		{
			mStartDragItemCallback(x,y,mId.uuid());
			mIsDragged = true;
			handled = TRUE;
		}
		else 
		{
			handled = mHandleDragItemCallback(x,y,mId.uuid(),LLAssetType::AT_WIDGET);
		}
	}
	else
	{
		handled = LLButton::handleHover(x, y, mask);
	}
	return handled;
}

void LLToolBarButton::onMouseEnter(S32 x, S32 y, MASK mask)
{
	LLUICtrl::onMouseEnter(x, y, mask);

	// Always highlight toolbar buttons, even if they are disabled
	mNeedsHighlight = TRUE;
}

void LLToolBarButton::onMouseCaptureLost()
{
	mIsDragged = false;
}