QT:简易文本编辑器

效果

main.cpp 代码：

#include "imgprocessor.h"
 
#include <QApplication>
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QFont f("ZYSong18030",12);//设置显示字段格式
    a.setFont(f);
    ImgProcessor w;
    w.show();
    return a.exec();
}

imgprocessor.h 代码：

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#ifndef IMGPROCESSOR_H
#define IMGPROCESSOR_H
 
#include <QMainWindow>
#include <QMenu>
#include <QMenuBar>
#include <QAction>
#include <QComboBox>
#include <QFontComboBox>
#include <QToolBar>
#include <QToolButton>
#include <QTextCharFormat>
#include <QTextStream>
#include <QPrinter>
#include <QPrintDialog>
#include <QTextDocument>
#include <QPainter>
 
#include "showwidget.h"
 
class ImgProcessor : public QMainWindow
{
    Q_OBJECT
 
public:
    ImgProcessor(QWidget *parent = nullptr);
    ~ImgProcessor();
    void createActions();//创建动作
    void createMenus();//创建菜单
    void createToolBars();//创建工具栏
    void loadFile(QString filename);
    void mergeFormat(QTextCharFormat format);
 
protected slots:
    void ShowNewFile(); // 新建文件
    void ShowOpenFile(); // 打开文件
    void ShowPrintText();// 打印文件
    void ShowPrintImage(); //图像打印
    void ShowZoomIn(); //放大
    void ShowZoomOut(); // 缩小
    void ShowRotate90(); //旋转90度
    void ShowRotate180();//旋转180度
    void ShowRotate270();//旋转270度
    void ShowMirrorVertical(); // 纵向镜像
    void ShowMirrorHorizontal();// 横向镜像
 
    /* 文本相关：槽 */
    void ShowFontComboBox(QString comboStr);
    void ShowSizeSpinBox(QString spinValue);
    void ShowBoldBtn();
    void ShowItalicBtn();
    void ShowUnderlineBtn();
    void ShowColorBtn();
    void ShowCurrentFormatChanged(const QTextCharFormat &fmt);
 
     /*  排版功能 */
    void ShowList(int );
    void ShowAlignment(QAction *act);
    void ShowCursorPositionChanged();
 
private:
    QMenu *fileMenu; // 各项菜单栏
    QMenu *zoomMenu;
    QMenu *rotateMenu;
    QMenu *mirrorMenu;
    QImage img;
    QString fileName;
    ShowWidget *showWidget;
    QAction *openFileAction; //文件菜单项
    QAction *NewfileAction;
    QAction *PrintTextAction;
    QAction *PrintImageAction;
    QAction *exitAction;
    QAction *copyAction; //编辑菜单项
    QAction *cutAction;
    QAction *pasteAction;
    QAction *aboutAction;
    QAction *zoomInAction;
    QAction *zoomOutAction;
    QAction *rotate90Action; //旋转菜单项
    QAction *rotate180Action;
    QAction *rotate270Action;
    QAction *mirrorVerticalAction; //镜像菜单项
    QAction *mirrorHorizontalAction;
    QAction *undoAction;
    QAction *redoAction;
    QToolBar *fileTool; //工具栏
    QToolBar *zoomTool;
    QToolBar *rotateTool;
    QToolBar *mirrorTool;
    QToolBar *doToolBar;
    /*  文本相关工具 */
    QLabel *fontLabel1;
    QFontComboBox *fontComboBox;
    QLabel *fontLabel2;
    QComboBox *sizeComboBox;
    QToolButton *boldBtn;
    QToolButton *italicBtn;
    QToolButton *underlineBtn;
    QToolButton *colorBtn;
    QToolBar *fontToolBar; // 字体工具栏
 
    /*  排版功能 */
    QLabel *listLabel;  // 排序设置项
    QComboBox *listComboBox;
    QActionGroup *actGrp;
    QAction *leftAction;
    QAction *rightAction;
    QAction *centerAction;
    QAction *justifyAction;
    QToolBar *listToolBar; // 排版工具
};
#endif // IMGPROCESSOR_H

imgprocessor.cpp 代码：

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#include "imgprocessor.h"
#include <QFile>
#include <QTextStream>
#include <QFileDialog>
#include <QPrinter>
#include <QColor>
#include <QColorDialog>
#include <QTextBlock>
#include <QTextList>
 
ImgProcessor::ImgProcessor(QWidget *parent)
    : QMainWindow(parent)
{
    setWindowTitle(tr("Easy Word")); //设置窗体标题
    showWidget = new ShowWidget(this);
    setCentralWidget(showWidget);
 
    // 在工具栏上嵌入控件
    //设置字体  p143
    fontLabel1 = new QLabel(tr("字体："));
    fontComboBox = new QFontComboBox;
    fontComboBox->setFontFilters(QFontComboBox::ScalableFonts);
    fontLabel2 = new QLabel(tr("字号："));
    sizeComboBox = new QComboBox;
    QFontDatabase db;
    foreach(int size ,db.standardSizes())
        sizeComboBox->addItem(QString::number(size));
    boldBtn = new QToolButton;
    boldBtn->setIcon(QIcon("./images/bold.png"));
    boldBtn->setCheckable(true);
    italicBtn = new QToolButton;
    italicBtn->setIcon(QIcon("./images/italic.png"));
    italicBtn->setCheckable(true);
    underlineBtn = new QToolButton;
    underlineBtn->setIcon(QIcon("./images/underline.png"));
    underlineBtn->setCheckable(true);
    colorBtn = new QToolButton;
    colorBtn->setIcon(QIcon("./images/color.png"));
    colorBtn->setCheckable(true);
 
     /*  排版功能 */
    listLabel = new QLabel(tr("排序"));
    listComboBox = new QComboBox;
    listComboBox->addItem("QTextListFormat::ListDisc");
    listComboBox->addItem("QTextListFormat::ListCircle");
    listComboBox->addItem("QTextListFormat::ListSquare");
    listComboBox->addItem("QTextListFormat::ListDecimal");
    listComboBox->addItem("QTextListFormat::ListLowerAlpha");
    listComboBox->addItem("QTextListFormat::ListUpperAlpa");
    listComboBox->addItem("QTextListFormat::ListLowerRoman");
    listComboBox->addItem("QTextListFormat::ListUpperRoman");
 
 
    /*创建动作、菜单、工具栏的函数*/
    createActions();
    createMenus();
    createToolBars();
    if(img.load("image.png")){
        // 在imageLabel对象中放置图片
        showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
    }
 
    //新建文件
    connect(NewfileAction,SIGNAL(triggered()),this,SLOT(ShowNewFile()));
    connect(openFileAction,SIGNAL(triggered()),this,SLOT(ShowOpenFile()));
    connect(PrintTextAction,SIGNAL(triggered()),this,SLOT(ShowPrintText()));
    connect(PrintImageAction,SIGNAL(triggered()),this,SLOT(ShowPrintImage()));
    connect(zoomOutAction,SIGNAL(triggered()),this,SLOT(ShowZoomOut()));
    connect(zoomInAction,SIGNAL(triggered()),this,SLOT(ShowZoomIn()));
 
    connect(rotate90Action,SIGNAL(triggered()),this,SLOT(ShowRotate90()));
    connect(rotate180Action,SIGNAL(triggered()),this,SLOT(ShowRotate180()));
    connect(rotate270Action,SIGNAL(triggered()),this,SLOT(ShowRotate270()));
 
    connect(mirrorHorizontalAction,SIGNAL(triggered()),this,SLOT(ShowMirrorHorizontal()));
    connect(mirrorVerticalAction,SIGNAL(triggered()),this,SLOT(ShowMirrorVertical()));
 
    /* 事件关联 */
    connect(fontComboBox, SIGNAL(activated(QString)),this,SLOT(ShowFontComboBox(QString)));
    connect(sizeComboBox, SIGNAL(activated(QString)),this,SLOT(ShowSizeSpinBox(QString)));
    connect(boldBtn, SIGNAL(clicked()),this,SLOT(ShowboldBtn()));
    connect(italicBtn, SIGNAL(clicked()),this,SLOT(ShowItalicBtn()));
    connect(underlineBtn, SIGNAL(clicked()),this,SLOT(ShowUnderlineBtn()));
    connect(colorBtn, SIGNAL(clicked()),this,SLOT(ShowColorBtn()));
    connect(showWidget, SIGNAL(currentChartFormatChanged(QTextCharFormat&)),this,SLOT(ShowCurrentFormatChanged(QTextCharFormat&)));
 
    /*  排版功能 */
    connect(listComboBox, SIGNAL(activated(int)),this, SLOT(ShowList(int)));
    connect(showWidget->text->document(), SIGNAL(undoAvailable(bool)),redoAction, SLOT(setEnabled(bool)));
    connect(showWidget->text->document(), SIGNAL(redoAvailable(bool)),redoAction, SLOT(setEnabled(bool)));
    connect(showWidget->text, SIGNAL(cursorPositionChanged()),this, SLOT(ShowCursorPositionChanged()));
}
 
ImgProcessor::~ImgProcessor()
{
}
 
void ImgProcessor::createActions()
{
    //“打开” 动作
    openFileAction = new QAction(QIcon("./images/open.png"),tr("打开"),this);
    openFileAction->setShortcut(tr("Ctrl+O"));
    openFileAction->setStatusTip(tr("打开一个文件"));
 
    NewfileAction = new QAction(QIcon("./images/new.png"),tr("新建"),this);
    NewfileAction->setShortcut(tr("Ctrl+N"));
    NewfileAction->setStatusTip(tr("新建一个文件"));
 
    exitAction= new QAction(QIcon("./images/exit.png"),tr("退出"),this);
    exitAction->setShortcut(tr("Ctrl+Q"));
    exitAction->setStatusTip(tr("退出程序"));
    connect(exitAction,SIGNAL(triggered()),this,SLOT(close()));
 
    copyAction = new QAction(QIcon("./images/copy.png"),tr("复制"),this);
    copyAction->setShortcut(tr("Ctrl+C"));
    copyAction->setStatusTip(tr("复制文件"));
    connect(copyAction,SIGNAL(triggered()),showWidget->text,SLOT(copy()));
 
    cutAction = new QAction(QIcon("./images/cut.png"),tr("剪切"),this);
    cutAction->setShortcut(tr("Ctrl+X"));
    cutAction->setStatusTip(tr("剪切文件"));
    connect(cutAction,SIGNAL(triggered()),showWidget->text,SLOT(cut()));
 
    pasteAction = new QAction(QIcon("./images/paste.png"),tr("粘贴"),this);
    pasteAction->setShortcut(tr("Ctrl+V"));
    pasteAction->setStatusTip(tr("粘贴文件"));
    connect(pasteAction,SIGNAL(triggered()),showWidget->text,SLOT(paste()));
    // ”“关于”“动作
    aboutAction = new QAction(QIcon("./images/about.png"),tr("关于"),this);
    connect(aboutAction, SIGNAL(triggered()),this, SLOT(QApplication::aboutQt()));
 
    //打印文件 动作
    PrintTextAction = new QAction(QIcon("./images/printText.png"),tr("打印文本"),this);
    PrintTextAction->setStatusTip(tr("打印一个文本"));
 
    //打印图片 动作
    PrintImageAction = new QAction(QIcon("./images/printImage.png"),tr("打印图片"),this);
    PrintImageAction->setStatusTip(tr("打印一幅图片"));
 
    zoomInAction = new QAction(QIcon("./images/zoomIn.png"),tr("放大"),this);
    zoomInAction->setStatusTip(tr("放大一幅图片"));
 
    zoomOutAction = new QAction(QIcon("./images/zoomOut.png"),tr("缩小"),this);
    zoomOutAction->setStatusTip(tr("缩小一幅图片"));
 
    rotate90Action = new QAction(QIcon("./images/rotate90.png"),tr("旋转90度"),this);
    rotate90Action->setStatusTip(tr("将一幅图片旋转90"));
 
    rotate180Action = new QAction(QIcon("./images/rotate180.png"),tr("旋转180度"),this);
    rotate180Action->setStatusTip(tr("将一幅图片旋转180"));
 
    rotate270Action = new QAction(QIcon("./images/rotate270.png"),tr("旋转270度"),this);
    rotate270Action->setStatusTip(tr("将一幅图片旋转270"));
 
    mirrorVerticalAction = new QAction(QIcon("./images/mirrorVertical.png"),tr("纵向镜像"),this);
    mirrorVerticalAction->setStatusTip(tr("对一幅图做纵向镜像"));
 
    mirrorHorizontalAction = new QAction(QIcon("./images/mirrorHorizontal.png"),tr("横向镜像"),this);
    mirrorHorizontalAction->setStatusTip(tr("对一幅图做横向镜像"));
 
    undoAction = new QAction(QIcon("./images/undo.png"),tr("撤销"),this);
    connect(undoAction,SIGNAL(triggered()),showWidget->text,SLOT(undo()));
 
    redoAction = new QAction(QIcon("./images/redo.png"),tr("重做"),this);
    connect(redoAction,SIGNAL(triggered()),showWidget->text,SLOT(redo()));
 
 
 
    /*  排序: 左对齐、右对齐、居中和两端对齐 */
    actGrp = new QActionGroup(this);
    leftAction = new QAction(QIcon("./images/left.png"),"左对齐",actGrp);
    leftAction->setCheckable(true);
    rightAction = new QAction(QIcon("./images/right.png"),"右对齐",actGrp);
    rightAction->setCheckable(true);
    centerAction = new QAction(QIcon("./images/center.png"),"居中",actGrp);
    centerAction->setCheckable(true);
    justifyAction = new QAction(QIcon("./images/justify.png"),"两端对齐",actGrp);
    justifyAction->setCheckable(true);
    connect(actGrp,SIGNAL(triggered(QAction*)),this, SLOT(ShowAlignment(QAction*)));
 
}
 
void ImgProcessor::createMenus()
{  // 文件菜单
    fileMenu = menuBar()->addMenu(tr("文件"));
    fileMenu->addAction(openFileAction);
    fileMenu->addAction(NewfileAction);
    fileMenu->addAction(PrintTextAction);
    fileMenu->addAction(PrintImageAction);
    fileMenu->addSeparator();
    fileMenu->addAction(exitAction);
    // 缩放菜单
    zoomMenu = menuBar()->addMenu(tr("编辑"));
    zoomMenu->addAction(copyAction);
    zoomMenu->addAction(cutAction);
    zoomMenu->addAction(pasteAction);
    zoomMenu->addAction(aboutAction);
    zoomMenu->addSeparator();
    zoomMenu->addAction(zoomInAction);
    zoomMenu->addAction(zoomOutAction);
    // 旋转菜单
    rotateMenu = menuBar()->addMenu(tr("旋转"));
    rotateMenu->addAction(rotate90Action);
    rotateMenu->addAction(rotate180Action);
    rotateMenu->addAction(rotate270Action);
    // 镜像菜单
    mirrorMenu = menuBar()->addMenu("镜像");
    mirrorMenu->addAction(mirrorVerticalAction);
    mirrorMenu->addAction(mirrorHorizontalAction);
 
}
 
void ImgProcessor::createToolBars()
{  // 文件工具条
    fileTool = addToolBar("File");
    fileTool->addAction(openFileAction);
    fileTool->addAction(NewfileAction);
    fileTool->addAction(PrintTextAction);
    fileTool->addAction(PrintImageAction);
    //编辑工具条
    zoomTool = addToolBar("Edit");
    zoomTool->addAction(copyAction);
    zoomTool->addAction(cutAction);
    zoomTool->addAction(pasteAction);
    zoomTool->addSeparator();
 
    zoomTool->addAction(zoomInAction);
    zoomTool->addAction(zoomOutAction);
    //旋转工具条
    rotateTool =  addToolBar("rotate");
    rotateTool->addAction(rotate90Action);
    rotateTool->addAction(rotate180Action);
    rotateTool->addAction(rotate270Action);
    //撤销和重做工具条
    doToolBar = addToolBar("doEdit");
    doToolBar->addAction(undoAction);
    doToolBar->addAction(redoAction);
 
    //字体工具条
    fontToolBar = addToolBar("Font");
    fontToolBar->addWidget(fontLabel1);
    fontToolBar->addWidget(fontComboBox);
    fontToolBar->addWidget(fontLabel2);
    fontToolBar->addWidget(sizeComboBox);
    fontToolBar->addSeparator();
    fontToolBar->addWidget(boldBtn);
    fontToolBar->addWidget(italicBtn);
    fontToolBar->addWidget(underlineBtn);
    fontToolBar->addSeparator();
    fontToolBar->addWidget(colorBtn);
 
    //排序工具条
    listToolBar = addToolBar("list");
    listToolBar->addWidget(listLabel);
    listToolBar->addWidget(listComboBox);
    listToolBar->addSeparator();
    listToolBar->addActions(actGrp->actions());
}
 
void ImgProcessor::loadFile(QString filename)
{// 读取文件内容功能
    printf("file Name:%s\n", (char*)filename.data());
    QFile file(filename);
    if(file.open(QIODevice::ReadOnly|QIODevice::Text)){
        QTextStream textStream(&file);
        while(!textStream.atEnd()){
            showWidget->text->append(textStream.readLine());
            printf("read line\n");
        }
        printf("end\n");
    }
}
 
 
void ImgProcessor::ShowNewFile()
{// 新建文件功能
    ImgProcessor *newImgProcessor = new ImgProcessor;
    newImgProcessor->show();
}
 
void ImgProcessor::ShowOpenFile()
{// 打开文件功能
    fileName = QFileDialog::getOpenFileName(this);
    if(!fileName.isEmpty()){
        if(showWidget->text->document()->isEmpty()){
            loadFile(fileName);
        }
        else{
            ImgProcessor *newImgProcessor = new ImgProcessor;
            newImgProcessor->show();
            newImgProcessor->loadFile(fileName);
        }
    }
}
 
void ImgProcessor::ShowPrintText()
{// 实现打印文本功能
    QPrinter printer;
    QPrintDialog printDialog(&printer,this);
    if(printDialog.exec()){
        // 获得QTextEdit对象的文档
        QTextDocument *doc = showWidget->text->document();
        doc->print(&printer);
    }
}
 
void ImgProcessor::ShowPrintImage()
{// 实现打印图像功能
    QPrinter printer; //新建一个QPainter对象
    QPrintDialog printDialog(&printer, this);
    if(printDialog.exec()){
        QPainter painter(&printer);
        QRect rect = painter.viewport();// 获得QPainter对象的视图矩形区域
        QSize size =  img.size();
        /* 按照图形的比例大小重新设置视图矩形区域**/
        size.scale(rect.size(), Qt::KeepAspectRatio);
        painter.setWindow(img.rect()); // 设置QPainter窗口大小为图像的大小
        painter.drawImage(0,0,img);// 打印图像
    }
}
 
void ImgProcessor::ShowZoomIn()
{// 实现图形放大功能
    if(img.isNull()){
        return;
    }
    QMatrix matrix;
    matrix.scale(2,2); //按照2倍比例对水平和垂直方向进行放大
    img = img.transformed(matrix);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowZoomOut()
{// 实现图形缩小功能
    if(img.isNull()){
        return;
    }
    QMatrix matrix;
    matrix.scale(0.5,0.5);//按照0.5倍比例对水平和垂直方向进行缩水
    img = img.transformed(matrix);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowRotate90()
{// 旋转90度
    if(img.isNull())
        return;
    QMatrix matrix;
    matrix.rotate(90);
    img=img.transformed(matrix);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowRotate180()
{// 旋转180度
    if(img.isNull())
        return;
    QMatrix matrix;
    matrix.rotate(180);
    img=img.transformed(matrix);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
void ImgProcessor::ShowRotate270()
{// 旋转270度
    if(img.isNull())
        return;
    QMatrix matrix;
    matrix.rotate(270);
    img=img.transformed(matrix);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowMirrorVertical()
{ // 图形的纵向镜像
    if(img.isNull())
        return;
    img = img.mirrored(false,true);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowMirrorHorizontal()
{// 图形的横向镜像
    if(img.isNull())
        return;
    img = img.mirrored(true,false);
    showWidget->imageLabel->setPixmap(QPixmap::fromImage(img));
}
 
void ImgProcessor::ShowFontComboBox(QString comboStr)
{
    QTextCharFormat fmt;
    fmt.setFontFamily(comboStr);
    mergeFormat(fmt);
}
 
void ImgProcessor::ShowSizeSpinBox(QString spinValue)
{
    QTextCharFormat fmt;
    fmt.setFontPointSize(spinValue.toFloat());
    showWidget->text->mergeCurrentCharFormat(fmt);
}
 
void ImgProcessor::ShowBoldBtn()
{  // 设置粗体
    QTextCharFormat fmt;
    fmt.setFontWeight(boldBtn->isChecked()?QFont::Bold:QFont::Normal);
    showWidget->text->mergeCurrentCharFormat(fmt);
}
 
void ImgProcessor::ShowItalicBtn()
{
    QTextCharFormat fmt;
    fmt.setFontItalic(italicBtn->isChecked());
    showWidget->text->mergeCurrentCharFormat(fmt);
}
 
void ImgProcessor::ShowUnderlineBtn()
{
    QTextCharFormat fmt;
    fmt.setFontUnderline(underlineBtn->isChecked());
    showWidget->text->mergeCurrentCharFormat(fmt);
}
 
void ImgProcessor::ShowColorBtn()
{
    QColor color = QColorDialog::getColor(Qt::red,this);
    if(color.isValid()){
        QTextCharFormat fmt;
        fmt.setForeground(color);
        showWidget->text->mergeCurrentCharFormat(fmt);
    }
}
 
void ImgProcessor::ShowCurrentFormatChanged(const QTextCharFormat &fmt)
{
    fontComboBox->setCurrentIndex(fontComboBox->findText((fmt.fontFamily())));
    sizeComboBox->setCurrentIndex(sizeComboBox->findText(QString::number(fmt.fontPointSize())));
    boldBtn->setChecked(fmt.font().bold());
    italicBtn->setChecked(fmt.fontItalic());
    underlineBtn->setChecked(fmt.fontUnderline());
}
 
void ImgProcessor::ShowList(int index)
{
    // 排序
    QTextCursor cursor = showWidget->text->textCursor();
    if(index!=0){
        QTextListFormat::Style style = QTextListFormat::ListDisc;
        switch(index){
        case 1:
            style = QTextListFormat::ListDisc;
            break;
        case 2:
            style = QTextListFormat::ListCircle;
            break;
        case 3:
            style = QTextListFormat::ListSquare;
            break;
        case 4:
            style = QTextListFormat::ListDecimal;
            break;
        case 5:
            style = QTextListFormat::ListLowerAlpha;
            break;
        case 6:
            style = QTextListFormat::ListUpperAlpha;
            break;
        case 7:
            style = QTextListFormat::ListLowerRoman;
            break;
        case 8:
            style = QTextListFormat::ListUpperRoman;
            break;
        }
        /*  设置缩进值 */
        cursor.beginEditBlock();
        QTextBlockFormat blockFmt = cursor.blockFormat();
        QTextListFormat listFmt;
        if(cursor.currentList()){
            listFmt = cursor.currentList()->format();
        }
        else{
            listFmt.setIndent(blockFmt.indent()+1);
            blockFmt.setIndent(0);
            cursor.setBlockFormat(blockFmt);
        }
        listFmt.setStyle(style);
        cursor.createList(listFmt);
        cursor.endEditBlock();
    }
    else{
        QTextBlockFormat bfmt;
        bfmt.setObjectIndex(-1);
        cursor.mergeBlockFormat(bfmt);
    }
}
 
void ImgProcessor::ShowAlignment(QAction *act)
{
    // 段落对齐
    if(act==leftAction)
        showWidget->text->setAlignment(Qt::AlignLeft);
    if(act==rightAction)
        showWidget->text->setAlignment(Qt::AlignRight);
    if(act==centerAction)
        showWidget->text->setAlignment(Qt::AlignCenter);
    if(act==justifyAction)
        showWidget->text->setAlignment(Qt::AlignJustify);
}
 
void ImgProcessor::ShowCursorPositionChanged()
{
    //响应文本中光标位置发生改变的信号
    if(showWidget->text->alignment()==Qt::AlignLeft)
        leftAction->setChecked(true);
    if(showWidget->text->alignment()==Qt::AlignRight)
        rightAction->setChecked(true);
    if(showWidget->text->alignment()==Qt::AlignCenter)
        centerAction->setChecked(true);
    if(showWidget->text->alignment()==Qt::AlignJustify)
        justifyAction->setChecked(true);
}
 
void ImgProcessor::mergeFormat(QTextCharFormat format)
{
    QTextCursor cursor = showWidget->text->textCursor();
    if(!cursor.hasSelection())
        cursor.select(QTextCursor::WordUnderCursor);
    cursor.mergeCharFormat(format);
    showWidget->text->mergeCurrentCharFormat(format);
}

showwidget.h 代码：

#ifndef SHOWWIDGET_H
#define SHOWWIDGET_H
 
#include <QWidget>
#include <QImage>
#include <QLabel>
#include <QTextEdit>
#include <QHBoxLayout>
 
class ShowWidget : public QWidget
{
    Q_OBJECT
public:
    explicit ShowWidget(QWidget *parent = nullptr);
    QImage img;
    QLabel *imageLabel;
    QTextEdit *text;
 
signals:
public slots:
};
 
#endif // SHOWWIDGET_H

showwidget.cpp代码

#include "showwidget.h"
 
ShowWidget::ShowWidget(QWidget *parent) : QWidget(parent)
{
    imageLabel =new QLabel;
    imageLabel->setScaledContents(true);
    text = new QTextEdit;
    QHBoxLayout *mainLayout = new QHBoxLayout(this);
    mainLayout->addWidget(imageLabel);
    mainLayout->addWidget(text);
}

　　在Qt5中，主窗体（MainWindow）是应用程序的核心组件，它通常承载着应用的主要功能和界面元素。在这个"文本编辑器"案例中，我们将深入探讨如何利用Qt5库来创建一个功能丰富的文本编辑器。Qt是一个跨平台的C++图形用户界面应用程序框架，提供了丰富的API来处理UI设计、事件处理以及与其他系统交互等功能。