WTL 的图片框

• 下载演示项目 - 150 Kb
• 下载源代码 - 6.1 Kb

引言

如果您想显示图像，这段代码非常有用。它可以从磁盘或包含在您程序中的资源中加载 *.bmp、*.jpg、*.png 和 *.gif 文件。该控件具有滚动条支持和内置上下文菜单，方便使用，可以禁用。

使用代码

以下示例假定您希望图片框位于主视图的客户端区域。

//  CMainFrm.h

#include "PictureBox.h"


class CMainFrame:
{
public:
  // Other code here

  
  WTL::CPictureBox  m_PictureBox;
};


// CMainFrm.cpp

LRESULT CMainFrame::OnCreate(UINT /*uMsg*/, WPARAM /*wParam*/, 
    LPARAM /*lParam*/, BOOL& /*bHandled*/)
{
  // Some code

  
  // Create the Picture Box

  m_hwndClient = m_PictureBox.Create(m_hWnd, rcDefault, NULL,
    WS_VISIBLE|WS_CHILD|WS_CLIPCHILDREN|WS_CLIPSIBLINGS, WS_EX_CLIENTEDGE);
  
  // The control is created, now we can load a picture in it.

  // To load an image in the Picture Box use any of the functions below

  
  // Some more code

}

CPictureBox 的创建函数与任何 CWindowImpl 派生类的创建函数一样。默认情况下，控件会将位图定位在视图的中心，并使用内置上下文菜单。

CPictureBox 函数

// Load an image from a file

// pszFileName is the path to the image

// the function returns true if succesfull, otherwise it returns false.

bool  LoadBitmapFromFile(LPCTSTR pszFileName);


// Load an image from a resource

// hInstance is the handle to the HINSTANCE you want to load from

// uiIDResource is the ID of the resource

// the function returns true if succesfull, otherwise it returns false.

bool  LoadBitmapFromID(HINSTANCE hInstance, UINT uiIDResource)


// Set the bitmap directly

// hBitmap is the Handle to the bitmap

// if  bOwner is true, the CPictureBox will 

// destroy the hBitamp when it is destroyed

// otherwise you have to clean up the hBitmap yourself

void  SetBitmap(HBITMAP hBitmap, bool bOwner = true)


// Detaches the bitmap from the CPictureBox and returns the bitmap

HBITMAP  GetBitmap()


// returns a save handle to the bitmap

HBITMAP  GetSaveBitmap()const


// if bCenter is true, the control will position 

// the bitmap in the center of the view

// otherwise the bitmap will be positioned in the 

// top left corner of the view

void  CenterPicture(bool bCenter)


// if bStretch is true, the control will stretct the 

// bitmap so that it fits the view

// otherwise the bitmap will be drawn normaly

void  StretchPicture(bool bStretch)


// if bUseMenu is true, the control will use the build in context menu

// otherwise the context menu will not be used

void  UseMenu(bool bUseMenu)

关注点

我编写这段代码是因为 WTL 没有可以显示 *.jpg、*.png、*.gif 或具有滚动条支持的类。

附加信息

有关更多信息、问题和错误报告，请访问我的网站：http://www.Trilobyte-Solutions.nl，或通过 bertwillems@trilobyte-solutions.nl 与我联系。