MFC 滑动条的重绘

MFC自带的滑动条的样子是这样的。

比较难看，所以需要重绘下，重绘后的样子是这样的。

代码如下：

CustomSliderCtr.h

#pragma once

// CCustomSliderCtr

class CCustomSliderCtr : public CSliderCtrl
{
    DECLARE_DYNAMIC(CCustomSliderCtr)

public:
    CCustomSliderCtr();
    virtual ~CCustomSliderCtr();

protected:
    afx_msg void OnPaint();
　　afx_msg void OnLButtonDown(UINT nFlags, CPoint point) ;
    void CustDraw(CDC *pDc);
    DECLARE_MESSAGE_MAP()
};

CustomSliderCtr.cpp

// CustomSliderCtr.cpp : 实现文件
//

#include "stdafx.h"
#include "CustomSliderCtr.h"

// CCustomSliderCtr

IMPLEMENT_DYNAMIC(CCustomSliderCtr, CSliderCtrl)

CCustomSliderCtr::CCustomSliderCtr()
{

}

CCustomSliderCtr::~CCustomSliderCtr()
{
}

BEGIN_MESSAGE_MAP(CCustomSliderCtr, CSliderCtrl)
    ON_WM_PAINT()
	ON_WM_LBUTTONDOWN()
END_MESSAGE_MAP()

// CCustomSliderCtr 消息处理程序

void CCustomSliderCtr::OnPaint()
{
    CSliderCtrl::OnPaint();
    CDC *pDc = GetDoc();
    CustDraw(pDc);
}

void CCustomSliderCtr::CustDraw(CDC *pDc)
{

    COLORREF colorLeft(SLIDER_LEFT_COLOR);

    COLORREF colorChannel(SlIDER_BK_COLOR);
    CPen penChannel(PS_DASHDOTDOT, 2, colorChannel);
    CBrush brushChannel;
    brushChannel.CreateSolidBrush(colorChannel);

    COLORREF colorThumb(SLIDER_THUMB_COLOR);
    CPen penThumb(PS_DASHDOTDOT, 2, colorThumb);
    CBrush brushThumb;
    brushThumb.CreateSolidBrush(colorThumb);

    CRect clientRect;
    GetClientRect(clientRect);

    CRect channelRect;
    GetChannelRect(&channelRect);

    //clientRect.bottom /= 2; 

    pDc->SetBkMode(TRANSPARENT);

    pDc->FillSolidRect(clientRect, DIALOG_BKCOLOR);

    clientRect.left = channelRect.left;
    clientRect.right = channelRect.right;

    pDc->FillSolidRect(clientRect, colorChannel);

    pDc->Draw3dRect(clientRect, colorChannel, colorChannel);

    CRect thumbRect;
    GetThumbRect(thumbRect);

    thumbRect.bottom *= 2;

    CRect leftRect;
    leftRect.left = clientRect.left;
    leftRect.top = clientRect.top;
    leftRect.bottom = clientRect.bottom;
    leftRect.right = thumbRect.left;

    pDc->SelectObject(&brushThumb);
    pDc->SelectObject(&penThumb);

    pDc->FillSolidRect(leftRect, colorLeft);

    pDc->Draw3dRect(leftRect, colorLeft, colorLeft);

    pDc->Ellipse(thumbRect);
}

void CCustomSliderCtr::OnLButtonDown(UINT nFlags, CPoint point)
{
    CSliderCtrl::OnLButtonDown(nFlags, point);
    CRect   rectClient,rectChannel;
    GetClientRect(rectClient);
    GetChannelRect(rectChannel);
    int nMax = 0;
    int nMin = 0;
    GetRange(nMin,nMax);
    int nPos = (nMax - nMin)*(point.x - rectClient.left - rectChannel.left)/(rectChannel.right - rectChannel.left);
    SetPos(nPos);
}  

　

　其中颜色定义

#define SlIDER_BK_COLOR RGB(192, 192, 192)
#define SLIDER_LEFT_COLOR RGB(148, 40, 255)
#define SLIDER_THUMB_COLOR RGB(240, 240, 240)
#define DIALOG_BKCOLOR RGB(201,227,253)