运行效果:
源代码
//item_i.hpp 抽象“图形元素”接口定义
#ifndef ITEM_I_HPP_INCLUDED
#define ITEM_I_HPP_INCLUDED
#include <wx/gdicmn.h>
#include <wx/dc.h>
class IItem
{
public:
//作为接口,记得要有虚析构
virtual ~IItem()
{
}
//使用DC画出自己
//注意:“画”的方法不应该修改对象的数据
virtual void Draw(wxDC& dc) const = 0; //纯虚函数
//开始在某一点上绘图
virtual void OnDrawStart(wxPoint const& point) = 0; //纯虚函数
//结束在某一点
virtual void OnDrawEnd(wxPoint const& point) = 0; //纯虚函数
};
#endif // ITEM_I_HPP_INCLUDED
//item_line.hpp 修改现有的LineItem类,实现IItem接口
#ifndef ITEM_LINE_HPP_INCLUDED
#define ITEM_LINE_HPP_INCLUDED
#include "item_i.hpp"
class LineItem : public IItem
{
public:
LineItem()
: _startPosition(0, 0), _endPosition(0, 0)
{
}
virtual void Draw(wxDC& dc) const;
// virtual void OnDrawStart(wxPoint const& point) //书上写法
void OnDrawStart(wxPoint const& point) override //C++11
{
_startPosition = point;
}
virtual void OnDrawEnd(wxPoint const& point) //写不写virtual不影响
{
_endPosition = point;
}
private:
//不写Logic后缀,但仍然是存储逻辑坐标
wxPoint _startPosition, _endPosition;
};
#endif // ITEM_LINE_HPP_INCLUDED
//item_line.cpp
#include "item_line.hpp"
void LineItem::Draw(wxDC& dc) const
{
dc.DrawLine(_startPosition, _endPosition);//就这一行,画直线
}
/***************************************************************
* Name: wxMyPainterApp.h
* Purpose: Defines Application Class
* Author: yanzhenxi (3065598272@qq.com)
* Created: 2023-12-21
* Copyright: yanzhenxi ()
* License:
**************************************************************/
#ifndef WXMYPAINTERAPP_H
#define WXMYPAINTERAPP_H
#include <wx/app.h>
class wxMyPainterApp : public wxApp
{
public:
virtual bool OnInit();
};
#endif // WXMYPAINTERAPP_H
/***************************************************************
* Name: wxMyPainterApp.cpp
* Purpose: Code for Application Class
* Author: yanzhenxi (3065598272@qq.com)
* Created: 2023-12-21
* Copyright: yanzhenxi ()
* License:
**************************************************************/
#include "wxMyPainterApp.h"
//(*AppHeaders
#include "wxMyPainterMain.h"
#include <wx/image.h>
//*)
IMPLEMENT_APP(wxMyPainterApp);
bool wxMyPainterApp::OnInit()
{
//(*AppInitialize
bool wxsOK = true;
wxInitAllImageHandlers();
if ( wxsOK )
{
wxMyPainterFrame* Frame = new wxMyPainterFrame(0);
Frame->Show();
SetTopWindow(Frame);
}
//*)
return wxsOK;
}
/***************************************************************
* Name: wxMyPainterMain.h
* Purpose: Defines Application Frame
* Author: yanzhenxi (3065598272@qq.com)
* Created: 2023-12-21
* Copyright: yanzhenxi ()
* License:
**************************************************************/
#ifndef WXMYPAINTERMAIN_H
#define WXMYPAINTERMAIN_H
#include <list>
#include "item_i.hpp"
//(*Headers(wxMyPainterFrame)
#include <wx/scrolwin.h>
#include <wx/sizer.h>
#include <wx/menu.h>
#include <wx/listbox.h>
#include <wx/frame.h>
#include <wx/statusbr.h>
//*)
class wxMyPainterFrame: public wxFrame
{
public:
wxMyPainterFrame(wxWindow* parent,wxWindowID id = -1);
virtual ~wxMyPainterFrame();
private:
//(*Handlers(wxMyPainterFrame)
void OnQuit(wxCommandEvent& event);
void OnAbout(wxCommandEvent& event);
void OnScrolledWindow1LeftDown(wxMouseEvent& event);
void OnScrolledWindow1MouseMove(wxMouseEvent& event);
void OnScrolledWindow1LeftUp(wxMouseEvent& event);
void OnScrolledWindow1Paint(wxPaintEvent& event);
//*)
//(*Identifiers(wxMyPainterFrame)
static const long ID_LISTBOX1;
static const long ID_SCROLLEDWINDOW1;
static const long idMenuQuit;
static const long idMenuNone;
static const long idMenuLine;
static const long idMenuRectangle;
static const long idMenuCircle;
static const long idMenuText;
static const long idMenuAbout;
static const long ID_STATUSBAR1;
//*)
//(*Declarations(wxMyPainterFrame)
wxMenuItem* MenuItemLine;
wxMenuItem* MenuItemNone;
wxScrolledWindow* ScrolledWindow1;
wxMenu* Menu3;
wxMenuItem* MenuItemText;
wxStatusBar* StatusBar1;
wxMenuItem* MenuItemRectangle;
wxMenuItem* MenuItemCircle;
wxListBox* ListBox1;
//*)
private:
void RemoveAllItems();
IItem* CreateNewItem();
/*每当用户鼠标按下,就创建一个新的_newItem,等画完之后(鼠标抬起),
就将它加入“_items”列表中。这也解释了为什么不需要“_drawing”这个标志,
因为当“_newItem”不为空,就说明用户正在画新的线。OnPaint事件的思路配套调整
为:每次都画出“_items”中的所有元素;然后如果“_newItem”不为空,则把用户正在
拖拽的线也画出来。*/
IItem* _newItem;
std::list <IItem*> _items;
DECLARE_EVENT_TABLE()
};
#endif // WXMYPAINTERMAIN_H
/***************************************************************
* Name: wxMyPainterMain.cpp
* Purpose: Code for Application Frame
* Author: yanzhenxi (3065598272@qq.com)
* Created: 2023-12-21
* Copyright: yanzhenxi ()
* License:
**************************************************************/
#include "wxMyPainterMain.h"
#include <wx/msgdlg.h>
#include <wx/dcclient.h>
#include "item_line.hpp"
//(*InternalHeaders(wxMyPainterFrame)
#include <wx/settings.h>
#include <wx/intl.h>
#include <wx/string.h>
//*)
//helper functions
enum wxbuildinfoformat {
short_f, long_f };
wxString wxbuildinfo(wxbuildinfoformat format)
{
wxString wxbuild(wxVERSION_STRING);
if (format == long_f )
{
#if defined(__WXMSW__)
wxbuild << _T("-Windows");
#elif defined(__UNIX__)
wxbuild << _T("-Linux");
#endif
#if wxUSE_UNICODE
wxbuild << _T("-Unicode build");
#else
wxbuild << _T("-ANSI build");
#endif // wxUSE_UNICODE
}
return wxbuild;
}
//(*IdInit(wxMyPainterFrame)
const long wxMyPainterFrame::ID_LISTBOX1 = wxNewId();
const long wxMyPainterFrame::ID_SCROLLEDWINDOW1 = wxNewId();
const long wxMyPainterFrame::idMenuQuit = wxNewId();
const long wxMyPainterFrame::idMenuNone = wxNewId();
const long wxMyPainterFrame::idMenuLine = wxNewId();
const long wxMyPainterFrame::idMenuRectangle = wxNewId();
const long wxMyPainterFrame::idMenuCircle = wxNewId();
const long wxMyPainterFrame::idMenuText = wxNewId();
const long wxMyPainterFrame::idMenuAbout = wxNewId();
const long wxMyPainterFrame::ID_STATUSBAR1 = wxNewId();
//*)
BEGIN_EVENT_TABLE(wxMyPainterFrame,wxFrame)
//(*EventTable(wxMyPainterFrame)
//*)
END_EVENT_TABLE()
wxMyPainterFrame::wxMyPainterFrame(wxWindow* parent,wxWindowID id)
: _newItem(nullptr)
{
//(*Initialize(wxMyPainterFrame)
wxMenuItem* MenuItemAbout;
wxMenu* Menu1;
wxMenuItem* MenuItemQuit;
wxBoxSizer* BoxSizer1;
wxMenuBar* MenuBar1;
wxMenu* Menu2;
Create(parent, id, wxEmptyString, wxDefaultPosition, wxDefaultSize, wxDEFAULT_FRAME_STYLE, _T("id"));
SetClientSize(wxSize(208,94));
BoxSizer1 = new wxBoxSizer(wxHORIZONTAL);
ListBox1 = new wxListBox(this, ID_LISTBOX1, wxDefaultPosition, wxSize(168,68), 0, 0, 0, wxDefaultValidator, _T("ID_LISTBOX1"));
BoxSizer1->Add(ListBox1, 0, wxALL|wxEXPAND, 5);
ScrolledWindow1 = new wxScrolledWindow(this, ID_SCROLLEDWINDOW1, wxDefaultPosition, wxDefaultSize, wxVSCROLL|wxHSCROLL, _T("ID_SCROLLEDWINDOW1"));
ScrolledWindow1->SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
BoxSizer1->Add(ScrolledWindow1, 1, wxALL|wxEXPAND, 5);
SetSizer(BoxSizer1);
MenuBar1 = new wxMenuBar();
Menu1 = new wxMenu();
MenuItemQuit = new wxMenuItem(Menu1, idMenuQuit, _("退出\tAlt-F4"), _("Quit the application"), wxITEM_NORMAL);
Menu1->Append(MenuItemQuit);
MenuBar1->Append(Menu1, _("文件[&F]"));
Menu3 = new wxMenu();
MenuItemNone = new wxMenuItem(Menu3, idMenuNone, _("无"), wxEmptyString, wxITEM_RADIO);
Menu3->Append(MenuItemNone);
MenuItemLine = new wxMenuItem(Menu3, idMenuLine, _("直线"), wxEmptyString, wxITEM_RADIO);
Menu3->Append(MenuItemLine);
MenuItemRectangle = new wxMenuItem(Menu3, idMenuRectangle, _("矩形"), wxEmptyString, wxITEM_RADIO);
Menu3->Append(MenuItemRectangle);
MenuItemCircle = new wxMenuItem(Menu3, idMenuCircle, _("圆形"), wxEmptyString, wxITEM_RADIO);
Menu3->Append(MenuItemCircle);
MenuItemText = new wxMenuItem(Menu3, idMenuText, _("文字"), wxEmptyString, wxITEM_RADIO);
Menu3->Append(MenuItemText);
MenuBar1->Append(Menu3, _("组件[&I]"));
Menu2 = new wxMenu();
MenuItemAbout = new wxMenuItem(Menu2, idMenuAbout, _("关于\tF1"), _("Show info about this application"), wxITEM_NORMAL);
Menu2->Append(MenuItemAbout);
MenuBar1->Append(Menu2, _("帮助[&H]"));
SetMenuBar(MenuBar1);
StatusBar1 = new wxStatusBar(this, ID_STATUSBAR1, 0, _T("ID_STATUSBAR1"));
int __wxStatusBarWidths_1[1] = { -1 };
int __wxStatusBarStyles_1[1] = { wxSB_NORMAL };
StatusBar1->SetFieldsCount(1,__wxStatusBarWidths_1);
StatusBar1->SetStatusStyles(1,__wxStatusBarStyles_1);
SetStatusBar(StatusBar1);
SetSizer(BoxSizer1);
Layout();
ScrolledWindow1->Connect(wxEVT_PAINT,(wxObjectEventFunction)&wxMyPainterFrame::OnScrolledWindow1Paint,0,this);
ScrolledWindow1->Connect(wxEVT_LEFT_DOWN,(wxObjectEventFunction)&wxMyPainterFrame::OnScrolledWindow1LeftDown,0,this);
ScrolledWindow1->Connect(wxEVT_LEFT_UP,(wxObjectEventFunction)&wxMyPainterFrame::OnScrolledWindow1LeftUp,0,this);
ScrolledWindow1->Connect(wxEVT_MOTION,(wxObjectEventFunction)&wxMyPainterFrame::OnScrolledWindow1MouseMove,0,this);
Connect(idMenuQuit,wxEVT_COMMAND_MENU_SELECTED,(wxObjectEventFunction)&wxMyPainterFrame::OnQuit);
Connect(idMenuAbout,wxEVT_COMMAND_MENU_SELECTED,(wxObjectEventFunction)&wxMyPainterFrame::OnAbout);
//*)
//设置滚动选项
ScrolledWindow1->SetScrollRate(10, 10);
ScrolledWindow1->SetVirtualSize(500, 480);
}
wxMyPainterFrame::~wxMyPainterFrame()
{
RemoveAllItems();
//(*Destroy(wxMyPainterFrame)
//*)
}
void wxMyPainterFrame::OnQuit(wxCommandEvent& event)
{
Close();
}
void wxMyPainterFrame::OnAbout(wxCommandEvent& event)
{
wxString msg = wxbuildinfo(long_f);
wxMessageBox(msg, _("Welcome to..."));
}
IItem* wxMyPainterFrame::CreateNewItem()
{
if(this->MenuItemLine->IsChecked())//小心,别写成IsCheckable()
{
return new LineItem();
}
return nullptr;
}
void wxMyPainterFrame::RemoveAllItems()
{
for(std::list<IItem*>::iterator it = _items.begin()
; it != _items.end(); ++it)
{
delete *it; //释放每个_newItem占据的内存
}
_items.clear(); //释放_items中元素(指向_newItem的指针)占据的内存
}
void wxMyPainterFrame::OnScrolledWindow1LeftDown(wxMouseEvent& event)
{
if(_newItem) return; //正在划线,返回
_newItem = this->CreateNewItem();
if(!_newItem) return;
_newItem->OnDrawStart(
ScrolledWindow1->CalcUnscrolledPosition(event.GetPosition()));
}
void wxMyPainterFrame::OnScrolledWindow1MouseMove(wxMouseEvent& event)
{
if(!_newItem) //不在绘画状态
{
return;//直接退出
}
_newItem->OnDrawEnd(//物理坐标转为逻辑坐标
ScrolledWindow1->CalcUnscrolledPosition(event.GetPosition()));
ScrolledWindow1->Refresh();
}
void wxMyPainterFrame::OnScrolledWindow1LeftUp(wxMouseEvent& event)
{
if(!_newItem) //不在绘画状态?
{
return;//直接退出
}
_newItem->OnDrawEnd(//物理坐标转为逻辑坐标
ScrolledWindow1->CalcUnscrolledPosition(event.GetPosition()));
_items.push_back(_newItem); //记录到列表中
_newItem = nullptr; //结束绘画状态
ScrolledWindow1->Refresh();
}
//将_items中的所有线都画出来
void wxMyPainterFrame::OnScrolledWindow1Paint(wxPaintEvent& event)
{
wxPaintDC dc(ScrolledWindow1);
//DoPrepareDC会自行调校
ScrolledWindow1->DoPrepareDC(dc);
//先画出list中的每一项
for(std::list <IItem*> :: const_iterator it = _items.begin()
; it != _items.end(); ++it)
{
IItem const* item = *it;
item->Draw(dc);
}
//如果刚巧用户正在画新项,把它也显示出来
//否则用户只能“盲画”了
if(_newItem)
{
_newItem->Draw(dc);
}
}