wg_scrollbar.cpp

一个小巧的嵌入式图形系统wGUI, 可以用VC编译

// wg_scrollbar.cpp
//
// CScrollBar class implementation
//
//
// Copyright (c) 2002 Rob Wiskow
// [e-mail]
//
// 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; either
// version 2.1 of the License, or (at your option) any later version.
//
// 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//


#include "wgui_include_config.h"
#include "wg_scrollbar.h"
#include "wg_message_server.h"
#include "wg_error.h"
#include "wg_resources.h"


namespace wGui
{

CScrollBar::CScrollBar(const CRect& WindowRect, CWindow* pParent, EScrollBarType ScrollBarType) :
	CWindow(WindowRect, pParent),
	m_ScrollBarType(ScrollBarType),
	m_iMin(0),
	m_iMax(100),
	m_iPosition(0),
	m_bDragging(false)
{
  m_sClassName = "CScrollBar";
	m_BGColor = DEFAULT_FG_COLOR;
	switch (m_ScrollBarType)
	{
	case VERTICAL:
		m_pBtnUpLeft = new CPictureButton(
			CRect(WindowRect.TopLeft(), CPoint(WindowRect.Right(), WindowRect.Top() + WindowRect.Width())),
			this, CwgBitmapResourceHandle(WGRES_UP_ARROW_BITMAP));
		m_pBtnDownRight = new CPictureButton(
			CRect(CPoint(WindowRect.Left(), WindowRect.Bottom() - WindowRect.Width()), WindowRect.BottomRight()),
			this, CwgBitmapResourceHandle(WGRES_DOWN_ARROW_BITMAP));
		m_ClientRect = CRect(0, m_pBtnUpLeft->GetWindowRect().Height() + 1,
			m_WindowRect.Width() - 1, m_WindowRect.Height() - m_pBtnUpLeft->GetWindowRect().Height() - 1);
		break;
	case HORIZONTAL:
		m_pBtnUpLeft = new CPictureButton(
			CRect(WindowRect.TopLeft(), CPoint(WindowRect.Left() + WindowRect.Height(), WindowRect.Bottom())),
			this, CwgBitmapResourceHandle(WGRES_LEFT_ARROW_BITMAP));
		m_pBtnDownRight = new CPictureButton(
			CRect(CPoint(WindowRect.Right() - WindowRect.Height(), WindowRect.Top()), WindowRect.BottomRight()),
			this, CwgBitmapResourceHandle(WGRES_RIGHT_ARROW_BITMAP));
		m_ClientRect = CRect(m_pBtnUpLeft->GetWindowRect().Width() + 1, 0,
			m_WindowRect.Width() - m_pBtnUpLeft->GetWindowRect().Width() - 1, m_WindowRect.Height() - 1);
		break;
	default:
		throw(Wg_Ex_App("CScrollBar::CScrollBar:  Unrecognized ScrollBar Type."));
		break;
	}
	m_ThumbRect = GetClientRect();
	SetPosition(0);
	CMessageServer::Instance().RegisterMessageClient(this, CMessage::MOUSE_BUTTONUP);
	CMessageServer::Instance().RegisterMessageClient(this, CMessage::MOUSE_MOVE);
	CMessageServer::Instance().RegisterMessageClient(this, CMessage::CTRL_LCLICK);
}


CScrollBar::~CScrollBar(void)
{

}


void CScrollBar::SetLimits(int iMin, int iMax)
{
	m_iMin = iMin;
	m_iMax = iMax;
	StartDrawProc();
}


void CScrollBar::SetPosition(int iPosition)
{
	m_iPosition = iPosition;
	if (m_iPosition < m_iMin)
	{
		m_iPosition = m_iMin;
	}
	if (m_iPosition > m_iMax)
	{
		m_iPosition = m_iMax;
	}
	switch (m_ScrollBarType)
	{
	case VERTICAL:
	{
		int yPos = static_cast<int>(GetClientRect().Top() + (GetClientRect().Height() - 16) * (static_cast<double>(m_iPosition - m_iMin) / (m_iMax - m_iMin)) - 1);
		m_ThumbRect.SetTop(yPos);
		m_ThumbRect.SetBottom(yPos + 16);
		break;
	}
	case HORIZONTAL:
	{
		int xPos = static_cast<int>(GetClientRect().Left() + (GetClientRect().Width() - 16) * (static_cast<double>(m_iPosition - m_iMin) / (m_iMax - m_iMin)) - 1);
		m_ThumbRect.SetLeft(xPos);
		m_ThumbRect.SetRight(xPos + 16);
		break;
	}
	default:
		throw(Wg_Ex_App("CScrollBar::SetPosition:  Unrecognized ScrollBar Type."));
		break;
	}
	StartDrawProc();
}


void CScrollBar::Draw(void) const
{
	CWindow::Draw();

	CPainter Painter(m_pSDLSurface);
	Painter.DrawRect(m_ThumbRect, false, COLOR_BLACK);
	CRect SubRect(m_ThumbRect);
	SubRect.Grow(-1);
	Painter.DrawRect(SubRect, true, COLOR_LIGHTGRAY, DEFAULT_FG_COLOR);
	Painter.DrawHLine(SubRect.Left(), SubRect.Right(), SubRect.Bottom(), COLOR_DARKGRAY);
	Painter.DrawVLine(SubRect.Top(), SubRect.Bottom(), SubRect.Right(), COLOR_DARKGRAY);
}


void CScrollBar::SetWindowRect(const CRect& WindowRect)
{
	CWindow::SetWindowRect(WindowRect);
	// Resposition the thumb rect and the button controls
	SetPosition(m_iPosition);
	switch (m_ScrollBarType)
	{
	case VERTICAL:
	{
		m_ThumbRect.SetLeft(m_WindowRect.Left());
		m_ThumbRect.SetRight(m_WindowRect.Right());
		m_pBtnUpLeft->SetWindowRect(CRect(m_WindowRect.TopLeft(),
			CPoint(m_WindowRect.Right(), m_WindowRect.Top() + m_WindowRect.Width())));
		m_pBtnDownRight->SetWindowRect(CRect(
			CPoint(m_WindowRect.Left(), m_WindowRect.Bottom() - m_WindowRect.Width()), m_WindowRect.BottomRight()));
		m_ClientRect.SetTop(m_pBtnUpLeft->GetWindowRect().Height() + 1);
		m_ClientRect.SetBottom(m_WindowRect.Height() - m_pBtnUpLeft->GetWindowRect().Height() - 1);
		break;
	}
	case HORIZONTAL:
	{
		m_ThumbRect.SetTop(m_WindowRect.Top());
		m_ThumbRect.SetBottom(m_WindowRect.Bottom());
		m_pBtnUpLeft->SetWindowRect(CRect(m_WindowRect.TopLeft(),
			CPoint(m_WindowRect.Left() + m_WindowRect.Height(), m_WindowRect.Bottom())));
		m_pBtnDownRight->SetWindowRect(CRect(
			CPoint(m_WindowRect.Right() - m_WindowRect.Height(), m_WindowRect.Top()), m_WindowRect.BottomRight()));
		m_ClientRect.SetLeft(m_pBtnUpLeft->GetWindowRect().Width() + 1);
		m_ClientRect.SetRight(m_WindowRect.Width() - m_pBtnUpLeft->GetWindowRect().Width() - 1);
		break;
	}
	default:
		throw(Wg_Ex_App("CScrollBar::SetWindowRect:  Unrecognized ScrollBar Type."));
		break;
	}
}


void CScrollBar::MoveWindow(const CPoint& MoveDistance)
{
	CWindow::MoveWindow(MoveDistance);
	m_ThumbRect = m_ThumbRect + MoveDistance;
}


bool CScrollBar::OnMouseButtonDown(CPoint Point, unsigned int Button)
{
	bool bResult = false;

 	if (! CWindow::OnMouseButtonDown(Point, Button) && m_bVisible && (m_ThumbRect.HitTest(Point) == CRect::RELPOS_INSIDE) &&
		(Button == CMouseMessage::LEFT))
	{
		m_bDragging = true;
		bResult = true;
	}

	return bResult;
}


bool CScrollBar::HandleMessage(CMessage* pMessage)
{
	bool bHandled = false;

	if (pMessage)
	{
		switch(pMessage->MessageType())
		{
		case CMessage::MOUSE_BUTTONUP:
		{
			CMouseMessage* pMouseMessage = dynamic_cast<CMouseMessage*>(pMessage);
			if (pMouseMessage && m_bDragging && pMouseMessage->Button == CMouseMessage::LEFT)
			{
				m_bDragging = false;
				CMessageServer::Instance().QueueMessage(new TIntMessage(CMessage::CTRL_VALUECHANGE, m_pParentWindow, this, m_iPosition));
				bHandled = true;
			}
			break;
		}
		case CMessage::MOUSE_MOVE:
			if (m_bDragging)
			{
				CMouseMessage* pMouseMessage = dynamic_cast<CMouseMessage*>(pMessage);
				if (pMouseMessage)
				{
					int iOldPosition = m_iPosition;
					switch (m_ScrollBarType)
					{
					case VERTICAL:
						SetPosition((pMouseMessage->Point.YPos() - GetClientRect().Top()) * (m_iMax - m_iMin) / GetClientRect().Height() + m_iMin);
						break;
					case HORIZONTAL:
						SetPosition((pMouseMessage->Point.XPos() - GetClientRect().Left()) * (m_iMax - m_iMin) / GetClientRect().Width() + m_iMin);
						break;
					default:
						throw(Wg_Ex_App("CScrollBar::HandleMessage:  Unrecognized ScrollBar Type."));
						break;
					}
					if (iOldPosition != m_iPosition)
					{
						CMessageServer::Instance().QueueMessage(new TIntMessage(CMessage::CTRL_VALUECHANGING, m_pParentWindow, this, m_iPosition));
					}
				}
			}
			break;
		case CMessage::CTRL_LCLICK:
		{
			if (pMessage->Destination() == this)
			{
				if (pMessage->Source() == m_pBtnUpLeft)
				{
					SetPosition(m_iPosition - 1);
					bHandled = true;
				}
				else if (pMessage->Source() == m_pBtnDownRight)
				{
					SetPosition(m_iPosition + 1);
					bHandled = true;
				}
				CMessageServer::Instance().QueueMessage(new TIntMessage(CMessage::CTRL_VALUECHANGE, m_pParentWindow, this, m_iPosition));
			}
			break;
		}
		default :
			bHandled = CWindow::HandleMessage(pMessage);
			break;
		}
	}

	return bHandled;
}

}