SuperMap IObjects C++组件学习笔记（一） - Hello iObjects C++

Hello iObjects C++

之前写了在qt下iObjects C++组件的环境搭建，现在可以开始使用iObjects C++进行开发了，作为一个尊重传统的程序员，我们还是从Hello iObjects开始吧。

一、纯后台处理的程序

假设我们暂时不需要UI，只希望让iObjects组件执行他的功能，比如打开一个工作空间，加载工作空间中的地图，由于没有UI，为了验证我们的地图加载成功，我们将其以图片格式输出出来。
首先创建一个类，完成我们想要的功能：
Hello.h

#ifndef HELLO_H#define HELLO_H#include <QObject>#include <QWidget>#include <QPaintEvent>#include <QResizeEvent>#include "Stream/ugdefs.h"#include "Engine/ugeng.h"namespace UGC{class UGWorkspace;class UGImage;class UGMap;}using namespace UGC;class Hello{    Q_OBJECTpublic:    explicit Hello();    ~Hello();    void openMap();    void outPutMapToPic();private:    //打开一张地图所需要的类    UGWorkspace* m_pWorkspace;    UGImage* m_pMapImage;    UGImage* m_pOldImage;    UGMap *m_pMap;    int m_width;    int m_height;    bool m_invalidate;private:    void init();};#endif // HELLO_H

hello.cpp

#include "Hello.h"#include "Workspace/UGWorkspace.h"#include "Graphics/UGImage.h"#include "Map/UGMap.h"Hello::Hello(void){    m_width = 800;    m_height = 600;    m_pMapImage = NULL;     //初始化    init();    //根据所需实例，使用对应方法    openMap();    // 调用输出地图的方法    outPutMapToPic();}Hello::~Hello(void){}void Hello::init(){    //初始化工作空间    m_pWorkspace = new UGWorkspace;    //初始化一个空的地图，用于图像的输出    m_pMap = new UGMap;    m_pMap->SetWorkspace(m_pWorkspace);    m_pMap->SetLineSmoothingMode(false);//设置关闭地图反走样}void Hello::openMap(){    //打开工作空间    UGString workspacePath = _U("../Data/HelloiObjects.smwu");    UGbool bl = m_pWorkspace->Open(workspacePath);    // 获取到工作空间中存储的第张地图的名字    UGString mapName = _U("HelloIObjects");    // 打开指定的名称的地图    UGMap *pMap = m_pMap;    pMap->Open(mapName);}void MapExample::outPutMapToPic(){    UGMap *pMap = m_pMap;    //调用Map类的outPut方法，指定输出位置和输出类型即可将图像输出    //这里的输出位置是我的桌面    pMap->OutputMapToFile(NULL,UGSize(m_width, m_height),_U("C:\\Users\\Ray\\Desktop\\outputImage.png"),UGint(UGFileType::PNG));}

编写一个程序调用该类即可即可在桌面看法到输出的地图

二、将地图展示到窗体应用中

2.1创建自己的MapControl类

因为iObjects C++组件是一个基础的GIS组件，为了利用该组件开发可视化的GIS应用，我们需要一个窗体应用库，这也是为什么从一开始搭建环境就是在Qt下的原因，我们需要Qt的ui库来实现我们的人机交互部分。
MapControl，顾名思义，就是对地图进行展示和控制的控件，我们继承于QWidget创建我们的UGMapControl类：

class UGMapControl : public QWidget

然后我们将前面我们写的后台处理的Hello代码迁移到我们的UGMapControl类中，并添加用于显示的方法：
首先为了对地图进行控制，我们将之前声明的

UGMap *m_pMap; 替换为 UGMapEditorWnd* m_pMapEditorWnd;以m_pMapEditorWnd->m_mapWnd.m_Map代替直接new的Map

然后重写继承自QWidget类的绘制事件和窗口大小改变事件

    virtual void paintEvent( QPaintEvent* event );    virtual void  resizeEvent ( QResizeEvent* event );

完整代码如下：

ugmapcontrol.h

#ifndef UGMAPCONTROL_H#define UGMAPCONTROL_H#include <QObject>#include <QWidget>#include <QPaintEvent>#include <QResizeEvent>#include "Stream/ugdefs.h"#include "Engine/ugeng.h"namespace UGC{class UGWorkspace;class UGMapEditorWnd;class UGImage;class UGGraphics;class UGDataset;class UGDataSource;class UGLayer;}using namespace UGC;class UGMapControl : public QWidget{    Q_OBJECTpublic:    explicit UGMapControl(QWidget* parent = 0);    ~UGMapControl();    //重写Qwidget的绘制事件    virtual void paintEvent( QPaintEvent* event );    //重写QWidget的窗口改变事件    virtual void  resizeEvent ( QResizeEvent* event );    void openMap();private:    UGWorkspace* m_pWorkspace;    UGMapEditorWnd* m_pMapEditorWnd;    UGImage* m_pMapImage;    UGImage* m_pOldImage;    QImage* m_pQimage;    int m_width;    int m_height;    bool m_invalidate;private:    void init();    void CreateUGGrpaphics(UGGraphics* &pGraphics);    void ReleaseUGGraphics(UGGraphics* &pGraphics);    void PaintToQPainter();    void Invalidate();};#endif // UGMAPCONTROL_H

ugmapcontrol.cpp

#include "ugmapcontrol.h"#include "MapEditor/UGMapEditorWnd.h"//打开地图用到#include "Graphics/UGGraphicsManager.h"//绘制图像用到#include "Engine/UGDataSourceManager.h"#include "Engine/UGDataSources.h"#include "Engine/UGDataSource.h"#include "Engine/UGDataset.h"#include "Engine/UGDatasetVector.h"#include <QPainter>UGMapControl::UGMapControl(QWidget *parent){    m_width = parent->width();    m_height = parent->height();    m_pMapImage = NULL;    init();    //openMap();}UGMapControl::~UGMapControl(){}void UGMapControl::paintEvent(QPaintEvent *event){    if (m_invalidate)    {        m_invalidate = FALSE;        UGGraphics* pGraphics = NULL;        CreateUGGrpaphics(pGraphics);        UGRect rcInvalid(0, 0, m_width, m_height);        m_pMapEditorWnd->OnDraw(pGraphics, rcInvalid, rcInvalid, false, false);        ReleaseUGGraphics(pGraphics);    }    PaintToQPainter();}void UGMapControl::resizeEvent(QResizeEvent *event){    QWidget::resizeEvent(event);    m_width = this->width();    m_height = this->height();    m_pMapEditorWnd->OnSize(NULL,UGRect(0, 0, m_width, m_height));    delete m_pMapImage;    m_pMapImage = UGGraphicsManager::NewImage();    m_pMapImage->CreateCompatibleImage(NULL, m_width, m_height);    this->Invalidate();}void UGMapControl::openMap(){    UGString workspacePath = _U("../Data/HelloiObjects.smwu");    UGbool bl = m_pWorkspace->Open(workspacePath);    // 获取到工作空间中存储的第张地图的名字    UGString mapName = _U("HelloIObjects");//m_pWorkspace->m_MapStorages.GetNameAt(0);    // 打开指定的名称的地图    UGMap *pMap = (UGMap*)&(m_pMapEditorWnd->m_mapWnd.m_Map);    pMap->Open(mapName);    // 全副显示地图    m_pMapEditorWnd->ViewEntire();    m_pMapEditorWnd->Refresh();    Invalidate();}void UGMapControl::init(){    UGGraphicsManager::SetCurGraphicsType(UGGraphics::GT_Windows);    //初始化地图控件    m_pMapEditorWnd = new UGMapEditorWnd();    m_pMapEditorWnd->Initialize();    m_pMapEditorWnd->SetUserAction(UGDrawParamaters::uaPointModeSelect);    //初始化工作空间    m_pWorkspace = new UGWorkspace;    //将工作空间绑定到地图控件的地图渲染窗口中的地图上，使地图控件可以对该工作空间上的地图进行控制    UGMap *pMap = (UGMap*)&(m_pMapEditorWnd->m_mapWnd.m_Map);    pMap->SetWorkspace(m_pWorkspace);    pMap->SetLineSmoothingMode(false);//设置关闭地图反走样}void UGMapControl::CreateUGGrpaphics(UGGraphics *&pGraphics){    pGraphics = UGC::UGGraphicsManager::NewGraphics();    pGraphics->CreateCompatibleGraphics(NULL);    m_pOldImage = pGraphics->SelectImage(m_pMapImage);}void UGMapControl::ReleaseUGGraphics(UGGraphics *&pGraphics){    pGraphics->SelectImage(m_pOldImage);    delete pGraphics;    pGraphics = NULL;}void UGMapControl::PaintToQPainter(){    m_pQimage = new QImage((UGC::UGbyte*)m_pMapImage->GetColors(), m_width, m_height, QImage::Format_ARGB32);    QPainter paint;    paint.begin(this);    QColor backGound(255, 255, 255);    paint.fillRect(0, 0, m_width, m_height, backGound);    paint.drawPixmap( QRect(0, 0, m_width, m_height),QPixmap::fromImage(m_pQimage->scaled(size())));    //paint.drawImage(QRectF(0, 0, m_width, m_height), *m_pQimage);    paint.end();    if (m_pQimage != NULL)    {        delete m_pQimage;        m_pQimage = NULL;    }}void UGMapControl::Invalidate(){    m_invalidate = TRUE;    this->update();}