MFC的视图窗口

如果那两个字没有颤抖，我不会发现我难受，那两个字是如果？分手？还是。。你好？

----  网易云热评

一、视图窗口作用

提供一个专门用于显示数据的窗口,并和用户进行交互

二、相关类

CView类,(父类为CWnd),封装了关于视图窗口的各种操作

三、视图窗口的使用

1、添加画图的宏

ON_WM_PAINT()

2、声明该方法

afx_msg void OnPaint();

3、重写方法

void CMyFrameWnd::OnPaint() {
    PAINTSTRUCT ps = { 0 };
    HDC hdc = ::BeginPaint(this->m_hWnd, &ps);
    ::TextOut(hdc, 100, 100, "我是框架窗口客户区",
        strlen("我是框架窗口客户区"));
    ::EndPaint(this->m_hWnd, &ps);
}

4、运行效果：

5、添加创建宏

ON_WM_CREATE()

6、申明该方法

afx_msg int OnCreate(LPCREATESTRUCT lpCreateStruct);

7、重写该方法

int CMyFrameWnd::OnCreate(LPCREATESTRUCT lpCreateStruct) {
    CMyView* pView = new CMyView;
    pView->Create(NULL, "MFCView",
        WS_CHILD | WS_VISIBLE | WS_BORDER, CRect(0, 0, 200, 200),
        this, AFX_IDW_PANE_FIRST);
    this->m_pViewActive = pView;
    return CFrameWnd::OnCreate(lpCreateStruct);
}

8、CMyview是抽象的，需要重写OnDraw方法

class CMyView :public CView {
public:
    virtual void OnDraw(CDC* pDC);
};
void CMyView::OnDraw(CDC* pDC) {
    
}

9、命令消息（WM_COMMAND）的处理顺序，

  View-->Frame-->App

10、新建一个菜单栏，测试上面的处理顺序

#include <afxwin.h>
#include "resource.h"
//新建视图类
class CMyView :public CView {
    DECLARE_MESSAGE_MAP()
public:
    virtual void OnDraw(CDC* pDC);
    afx_msg void OnPaint();
    afx_msg void OnNew();
};
BEGIN_MESSAGE_MAP(CMyView, CView)
    ON_COMMAND(ID_XJ, OnNew)
    ON_WM_PAINT()
END_MESSAGE_MAP()
void CMyView::OnNew() {
    AfxMessageBox("视图类处理了新建被点击发出的COMMAND消息");
}
void CMyView::OnPaint() {
    PAINTSTRUCT ps = { 0 };
    HDC hdc = ::BeginPaint(this->m_hWnd, &ps);
    ::TextOut(hdc, 200, 200, "CMyView::OnPaint", strlen("CMyView::OnPaint"));
    ::EndPaint(this->m_hWnd, &ps);
}
void CMyView::OnDraw(CDC* pDC) {
    //在视图窗口画图
    pDC->TextOut(100, 100, "CMyView::OnDraw");
}
//框架类
class CMyFrameWnd :public CFrameWnd {
    DECLARE_MESSAGE_MAP()
public:
    afx_msg void OnPaint();
    afx_msg int OnCreate(LPCREATESTRUCT lpCreateStruct);
};
BEGIN_MESSAGE_MAP(CMyFrameWnd, CFrameWnd)
    ON_WM_PAINT()
    ON_WM_CREATE()
END_MESSAGE_MAP()
int CMyFrameWnd::OnCreate(LPCREATESTRUCT lpCreateStruct) {
    CMyView* pView = new CMyView;
    pView->Create(NULL, "MFCView",
        WS_CHILD | WS_VISIBLE | WS_BORDER, CRect(0, 0, 200, 200),
        this, AFX_IDW_PANE_FIRST);
    //默认选中视图窗口
    this->m_pViewActive = pView;
    return CFrameWnd::OnCreate(lpCreateStruct);
}
//画图
void CMyFrameWnd::OnPaint() {
    PAINTSTRUCT ps = { 0 };
    HDC hdc = ::BeginPaint(this->m_hWnd, &ps);
    ::TextOut(hdc, 100, 100, "我是框架窗口客户区",
        strlen("我是框架窗口客户区"));
    ::EndPaint(this->m_hWnd, &ps);
}
//应用类
class CMyWinApp :public CWinApp {
public:
    virtual BOOL InitInstance();
};
CMyWinApp theApp;
BOOL CMyWinApp::InitInstance()
{
    CMyFrameWnd* pFrame = new CMyFrameWnd;
    pFrame->Create(NULL, "视图窗口", WS_OVERLAPPEDWINDOW,
        CFrameWnd::rectDefault, NULL,
        MAKEINTRESOURCE(IDR_MENU1));
    m_pMainWnd = pFrame;
    pFrame->ShowWindow(SW_SHOW);
    pFrame->UpdateData();
    return TRUE;
}

11、运行结果