Action、Menus、ToolBars主窗体构成的实现

QMainWindow是一个为用户提供主窗口程序的类，包含一个菜单栏（menu bar）、多个工具栏（tool bars）、多个锚接部件（dock widgets）、一

个状态栏（status bar）及一个中心部件（central widget），是许多应用程序的基础，如文本编辑器、图片编辑器等。本章将对此进行详细介绍。其

界面布局如图所示

1．动作（Action）的实现

          以下是实现基本文件操作的动作（Action）的代码。

          以下是实现打印文本和图像、图像缩放、旋转和镜像的动作（Action）的代码。

2．菜单（Menus）的实现

          在实现了各个动作之后，需要将它们通过菜单、工具栏或快捷键的方式体现出来，以下是菜单的实现函数createMenus()代码。

3．工具栏（ToolBars）的实现

          接下来实现相对应的工具栏createToolBars()，主窗口的工具栏上可以有多个工具条，通常采用一个菜单对应一个工具条的方式，也可根据需要进行工具条的划分。

项目运行效果

showwidget.h

#ifndef SHOWWIDGET_H

#define SHOWWIDGET_H

#include <QWidget>

#include <QImage>

#include <QTextEdit>

#include <QLabel>

class ShowWidget : public QWidget

{

    Q_OBJECT

public:

    explicit ShowWidget(QWidget *parent = 0);

    QImage img;

    QLabel *imageLabel;

    QTextEdit *text;

};

#endif // SHOWWIDGET_H

showwidget.cpp

#include "showwidget.h"

#include <QHBoxLayout>

/*

 * 水平方向添加一个imageLabel，text

 * 其中imageLabel设置显示图片自动缩放

*/

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);

}

imageprocessor.h

#ifndef IMAGEPROCESSOR_H

#define IMAGEPROCESSOR_H

#include <QMainWindow>

#include <QImage>

#include <QLabel>

#include <QMenu>

#include <QMenuBar>

#include <QAction>

#include <QComboBox>

#include <QSpinBox>

#include <QToolBar>

#include <QFontComboBox>

#include <QToolButton>

#include <QTextCharFormat>

#include "showwidget.h"

class ImageProcessor : public QMainWindow

{

    Q_OBJECT

public:

    ImageProcessor(QWidget *parent = 0);

    ~ImageProcessor();

    void createActions();    //创建动作

    void createMenus();     //创建菜单

    void createToolBars();  //创建工具栏

    void loadFile(QString filename);        //加载文件

    void mergeFormat(QTextCharFormat);      //合并板式

private:

    //各项菜单栏

    QMenu *fileMenu;            //文件

    QMenu *zoomMenu;            //编辑

    QMenu *rotateMenu;          //旋转

    QMenu *mirrorMenu;          //镜像

    QImage img;

    QString fileName;

    ShowWidget *showWidget;

    //文件菜单项

    QAction *openFileAction;    //打开文件 Ctrl + O

    QAction *NewFileAction;     //新建文件 Ctrl + N

    QAction *PrintTextAction;   //打印字体

    QAction *PrintImageAction;  //打印图像

    QAction *exitAction;        //退出    Ctrl + Q

    //编辑菜单项

    QAction *copyAction;        //复制 Ctrl + C

    QAction *cutAction;         //剪切 Ctrl + V

    QAction *pasteAction;       //粘贴 Ctrl + P

    QAction *aboutAction;        //关于

    QAction *zoomInAction;      //放大

    QAction *zoomOutAction;     //缩小

    //旋转菜单

    QAction *rotate90Action;

    QAction *rotate180Action;

    QAction *rotate270Action;

    //镜像菜单

    QAction *mirrorVerticalAction;

    QAction *mirrorHorizontalAction;

    //上一步，下一步

    QAction *undoAction;

    QAction *redoAction;

    //工具栏

    QToolBar *fileTool;

    QToolBar *zoomTool;

    QToolBar *rotateTool;

    QToolBar *mirrorTool;

    QToolBar *doToolBar;

    //字体设置项

    QLabel *fontLabel1;

    QFontComboBox *fontComboBox;

    QLabel *fontLabel2;

    QComboBox *sizeComboBox;

    QToolButton *boldBtn;

    QToolButton *italicBtn;

    QToolButton *underlineBtn;

    QToolButton *colorBtn;

    //字体工具栏

    QToolBar *fontToolBar;

    QLabel *listLabel;

    QComboBox *listComboBox;

    QActionGroup *actGrp;

    QAction *leftAction;

    QAction *rightAction;

    QAction *centerAction;

    QAction *justifyAction;

    QToolBar *listToolBar;

protected slots:

    void ShowNewFile();

    void ShowOpenFile();

    void ShowPrintText();

    void ShowPrintImage();

    void ShowZoomIn();

    void ShowZoomOut();

    void ShowRotate90();

    void ShowRotate180();

    void ShowRotate270();

    void ShowMirrorVertical();

    void ShowMirrorHorizontal();

    void ShowFontComboBox(QString comboStr);

    void ShowSizeSpinBox(QString spinValue);

    void ShowBoldBtn();

    void ShowItalicBtn();

    void ShowUnderlineBtn();

    void ShowColorBtn();

    void ShowCurrentFormatChanged(const QTextCharFormat &fmt);

    void ShowList(int index);

    void ShowAlignment(QAction *act);

    void ShowCursorPositionChanged();

};

#endif // IMAGEPROCESSOR_H

imageprocessor.cpp

#include "imageprocessor.h"

#include <QFileDialog>

#include <QFile>

#include <QTextStream>

#include <QtPrintSupport/QPrinter>

#include <QtPrintSupport/QPrintDialog>

#include <QPainter>

#include <QTextCharFormat>

#include <QTextList>

#include <QColorDialog>

#include <QColor>

/*

 * QFontComboBox的setFontFilters接口可过滤只在下拉框中显示某一类字体，默认情况QFontComboBox::AllFonts列出所有字体

 * QFontDatabase实现在字号下拉列表框中填充各种不同的字号数目，QFontDatabase类用于表示当前系统中所有可用格式信息，主要是

 * 字体和字号大小，standardSizes()函数返回可用标准字号的列表，并将它们插入到字号下拉列表框中，本实例只列出字号

*/

ImageProcessor::ImageProcessor(QWidget *parent)

    : QMainWindow(parent)

{

    //设置主窗口大小

    this->resize (830, 260);

    setWindowTitle (tr("Easy Word"));

    showWidget = new ShowWidget(this);

    setCentralWidget (showWidget);

    //在工具栏上嵌入式控件

    //设置字体

    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("bold.png"));

    boldBtn->setCheckable(true);

    italicBtn =new QToolButton;

    italicBtn->setIcon(QIcon("italic.png"));

    italicBtn->setCheckable(true);

    underlineBtn =new QToolButton;

    underlineBtn->setIcon(QIcon("underline.png"));

    underlineBtn->setCheckable(true);

    colorBtn =new QToolButton;

    colorBtn->setIcon(QIcon("color.png"));

    colorBtn->setCheckable(true);

    //排序

    listLabel = new QLabel(tr("排序"));

    listComboBox = new QComboBox;

    listComboBox->addItem("Standard");

    listComboBox->addItem("QTextListFormat::ListDisc");

    listComboBox->addItem("QTextListFormat::ListCircle");

    listComboBox->addItem("QTextListFormat::ListSquare");

    listComboBox->addItem("QTextListFormat::ListDecimal");

    listComboBox->addItem("QTextListFormat::ListLowerAlpha");

    listComboBox->addItem("QTextListFormat::ListUpperAlpha");

    listComboBox->addItem("QTextListFormat::ListLowerRoman");

    listComboBox->addItem("QTextListFormat::ListUpperRoman");

    createActions();

    createMenus();

    createToolBars();

    //在imageLabel对象中放置一个图像

    if(img.load ("image.png"))

    {

        showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

    }

    connect (fontComboBox, SIGNAL(activated(QString)), this, SLOT(ShowFontComboBox(QString)));

    connect (sizeComboBox, SIGNAL(activated(QString)), this, SLOT(ShowSizeSpinBox(QString)));

    connect (boldBtn, SIGNAL(clicked(bool)), this, SLOT(ShowBoldBtn()));

    connect (italicBtn, SIGNAL(clicked(bool)), this, SLOT(ShowItalicBtn()));

    connect (underlineBtn, SIGNAL(clicked(bool)), this, SLOT(ShowUnderlineBtn()));

    connect (colorBtn, SIGNAL(clicked(bool)), this, SLOT(ShowColorBtn()));

    connect (showWidget->text, SIGNAL(currentCharFormatChanged(QTextCharFormat)), this, SLOT(ShowCurrentFormatChanged(QTextCharFormat)));

    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()));

}

ImageProcessor::~ImageProcessor()

{

}

void ImageProcessor::createActions ()

{

    //“打开”动作

    openFileAction = new QAction(QIcon("open.png"),tr("打开"),this);

    openFileAction->setShortcut(tr("Ctrl+O"));

    openFileAction->setStatusTip(tr("打开一文件"));

    connect(openFileAction,SIGNAL(triggered()),this,SLOT(ShowOpenFile()));

    //“新建”动作

    NewFileAction = new QAction(QIcon("new.png"), tr("新建"), this);

    NewFileAction->setShortcut (tr("Ctrl+N"));

    NewFileAction->setStatusTip (tr("新建一个文件"));

    connect (NewFileAction, SIGNAL(triggered(bool)), this, SLOT(ShowNewFile()));

    //"打印文本"动作

    PrintTextAction = new QAction(QIcon("printText.png"), tr("打印文本"), this);

    PrintTextAction->setStatusTip (tr("打印一个文本"));

    connect (PrintTextAction, SIGNAL(triggered(bool)), this, SLOT(ShowPrintText()));

    //“打印图像”动作

    PrintImageAction = new QAction(QIcon("printImage.png"), tr("打印图像"), this);

    PrintImageAction->setStatusTip (tr("打印一个图像"));

    connect (PrintImageAction, SIGNAL(triggered(bool)), this, SLOT(ShowPrintImage()));

    //"退出"动作

    exitAction = new QAction(tr("退出"), this);

    exitAction->setShortcut (tr("Ctrl+Q"));

    exitAction->setStatusTip (tr("退出程序"));

    connect (exitAction, SIGNAL(triggered(bool)), this, SLOT(close()));

    //"复制"动作

    copyAction = new QAction(QIcon("copy.png"), tr("复制"), this);

    copyAction->setShortcut (tr("Ctrl+C"));

    copyAction->setStatusTip (tr("复制文件"));

    connect (copyAction, SIGNAL(triggered(bool)), showWidget->text, SLOT(copy()));

    //"剪切"动作

    cutAction = new QAction(QIcon("cut.png"), tr("剪切"), this);

    cutAction->setShortcut (tr("Ctrl+X"));

    cutAction->setStatusTip (tr("剪切文件"));

    connect (cutAction, SIGNAL(triggered(bool)), showWidget->text, SLOT(cut()));

    //"粘贴"动作

    pasteAction = new QAction(QIcon("paste.png"), tr("粘贴"), this);

    pasteAction->setShortcut (tr("Ctrl+V"));

    pasteAction->setStatusTip (tr("粘贴文件"));

    connect (pasteAction, SIGNAL(triggered(bool)), showWidget->text, SLOT(paste()));

    //"关于"动作

    aboutAction = new QAction(tr("关于"), this);

    connect(aboutAction,SIGNAL(triggered()),this,SLOT(QApplication::aboutQt()));

    //“放大”动作

    zoomInAction = new QAction(QIcon("zoomin.png"), tr("放大"), this);

    zoomInAction->setStatusTip (tr("放大一张图片"));

    connect (zoomInAction, SIGNAL(triggered(bool)), this, SLOT(ShowZoomIn()));

    //"缩小"动作

    zoomOutAction = new QAction(QIcon("zoomout.png"), tr("放大"), this);

    zoomOutAction->setStatusTip (tr("缩小一张图片"));

    connect (zoomOutAction, SIGNAL(triggered(bool)), this, SLOT(ShowZoomOut()));

    //实现图像旋转的动作

    //旋转90°

    rotate90Action = new QAction(QIcon("rotate90.png"), tr("旋转90°"), this);

    rotate90Action->setStatusTip (tr("将一幅图旋转90°"));

    connect (rotate90Action, SIGNAL(triggered(bool)), this, SLOT(ShowRotate90()));

    //旋转180°

    rotate180Action = new QAction(QIcon("rotate180.png"), tr("旋转180°"), this);

    rotate180Action->setStatusTip (tr("将一幅图旋转180°"));

    connect (rotate180Action, SIGNAL(triggered(bool)), this, SLOT(ShowRotate180()));

    //旋转270°

    rotate270Action = new QAction(QIcon("rotate270.png"), tr("旋转270°"), this);

    rotate270Action->setStatusTip (tr("将一幅图旋转270°"));

    connect (rotate270Action, SIGNAL(triggered(bool)), this, SLOT(ShowRotate270()));

    //实现图像镜像的动作

    //纵向镜像

    mirrorVerticalAction = new QAction(tr("纵向镜像"), this);

    mirrorVerticalAction->setStatusTip (tr("对一张图坐标纵向镜像"));

    connect (mirrorVerticalAction, SIGNAL(triggered(bool)), this, SLOT(ShowMirrorVertical()));

    //横向镜像

    mirrorHorizontalAction = new QAction(tr("横向镜像"), this);

    mirrorHorizontalAction->setStatusTip (tr("对一张图坐标横向镜像"));

    connect (mirrorHorizontalAction, SIGNAL(triggered(bool)), this, SLOT(ShowMirrorHorizontal()));

    //实现撤销和重做的动作

    //撤销

    undoAction = new QAction(QIcon("undo.png"), tr("撤销"), this);

    connect (undoAction, SIGNAL(triggered(bool)), showWidget->text, SLOT(undo()));

    //重做

    redoAction = new QAction(QIcon("redo.png"), tr("重做"), this);

    connect (redoAction, SIGNAL(triggered(bool)), showWidget->text, SLOT(redo()));

    //实现撤销和重做的动作（Action）

    actGrp = new QActionGroup(this);

    leftAction = new QAction(QIcon("left.png"), "左对齐", actGrp);

    leftAction->setCheckable (true);

    rightAction = new QAction(QIcon("right.png"), "右对齐", actGrp);

    rightAction->setCheckable (true);

    centerAction = new QAction(QIcon("center.png"), "右对齐", actGrp);

    centerAction->setCheckable (true);

    justifyAction = new QAction(QIcon("justify.png"), "右对齐", actGrp);

    justifyAction->setCheckable (true);

    connect (actGrp, SIGNAL(triggered(QAction*)), this, SLOT(ShowAlignment(QAction*)));

}

void ImageProcessor::createMenus ()

{

    //文件菜单

    fileMenu =menuBar()->addMenu(tr("文件"));

    fileMenu->addAction(openFileAction);

    fileMenu->addAction(NewFileAction);

    fileMenu->addAction(PrintTextAction);

    fileMenu->addAction(PrintImageAction);

    fileMenu->addAction(exitAction);

    //编辑菜单

    zoomMenu = menuBar ()->addMenu (tr("编辑"));

    zoomMenu->addAction(copyAction);

    zoomMenu->addAction(cutAction);

    zoomMenu->addAction(pasteAction);

    zoomMenu->addAction(aboutAction);

    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 (tr("镜像"));

    mirrorMenu->addAction(mirrorVerticalAction);

    mirrorMenu->addAction(mirrorHorizontalAction);

}

void ImageProcessor::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);

    //撤消和重做工具条

    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();    //添加分隔符

    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 ());

}

/*

 * 显示新建文件

*/

void ImageProcessor::ShowNewFile()

{

    ImageProcessor *newImageProcessor = new ImageProcessor;

    newImageProcessor->show ();

}

/*

 * fileName获取打开文件的（父窗口，标题名，默认的目录，过滤文件类型）

*/

void ImageProcessor::ShowOpenFile()

{

    fileName = QFileDialog::getOpenFileName (this, "打开");

    if(!fileName.isEmpty ())

    {

        /*判断显示的内容空时，从新加载*/

        if(showWidget->text->document ()->isEmpty ())

        {

            loadFile (fileName);

        }

        else

        {

            ImageProcessor *newImageProcessor = new ImageProcessor;

            newImageProcessor->show ();

            newImageProcessor->loadFile (fileName);

        }

    }

}

void ImageProcessor::loadFile (QString filename)

{

    printf ("file name: %s\n", 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");

    }

}

/*

 * QPrintDialog是Qt提供的标准打印对话框

*/

void ImageProcessor::ShowPrintText()

{

    QPrinter printer;

    QPrintDialog printDialog(&printer, this);

    /*判断打印机对话框显示后用户是否单击“打印”按钮*/

    if(printDialog.exec ())

    {

        QTextDocument *doc = showWidget->text->document ();

        doc->print (&printer);

    }

}

/*

 * QPrintDialog是Qt提供的标准打印对话框

*/

void ImageProcessor::ShowPrintImage()

{

    QPrinter printer;

    QPrintDialog printDialog(&printer, this);

    /*判断打印机对话框显示后用户是否单击“打印”按钮*/

    if(printDialog.exec ())

    {

        QPainter painter(&printer);         //指定绘图设备为一个QPrinter对象

        QRect rect = painter.viewport();    //获取QPainter对象的视图矩形区域

        QSize size = img.size ();

        /*按照图形的大小重新设置视图矩形的区域*/

        size.scale (rect.size (), Qt::KeepAspectRatio);

        painter.setViewport(rect.x (), rect.y (), rect.width (), rect.height ());

        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

    }

}

/*

 * QMatrix类提供了世界坐标系统的二维转换功能setScaledContents用来设置控件的

 * scaledContents属性确定是否根据其大小自动调节内容大小，以便使内容充满整个有效

 * 区域按照2倍比例对水平和垂直方向进行放大，将当前显示的图形按照该坐标矩阵进行转换

*/

void ImageProcessor::ShowZoomIn()

{

    if(img.isNull ())

        return;

    QMatrix martix;

    martix.scale (2, 2);

    img = img.transformed (martix);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

void ImageProcessor::ShowZoomOut()

{

    if(img.isNull ())

        return;

    QMatrix martix;

    martix.scale (0.5, 0.5);

    img = img.transformed (martix);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

void ImageProcessor::ShowRotate90()

{

    if(img.isNull ())

        return;

    QMatrix martix;

    martix.rotate (90);

    img = img.transformed (martix);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

void ImageProcessor::ShowRotate180()

{

    if(img.isNull ())

        return;

    QMatrix martix;

    martix.rotate (180);

    img = img.transformed (martix);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

void ImageProcessor::ShowRotate270()

{

    if(img.isNull ())

        return;

    QMatrix martix;

    martix.rotate (270);

    img = img.transformed (martix);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

/* 镜像函数

 * mirror(bool horizontal, bool vertical)

*/

void ImageProcessor::ShowMirrorVertical()

{

    if(img.isNull ())

        return;

    img = img.mirrored (false, true);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

void ImageProcessor::ShowMirrorHorizontal()

{

    if(img.isNull ())

        return;

    img = img.mirrored (true, false);

    showWidget->imageLabel->setPixmap (QPixmap::fromImage (img));

}

/*

 * 设置字体的格式

 * 选择的字体名称设置给QTextCharFormat对象

 * 将新的格式应用到光标选区内的字符

*/

void ImageProcessor::ShowFontComboBox(QString comboStr)

{

    QTextCharFormat fmt;

    fmt.setFontFamily (comboStr);

    mergeFormat(fmt);

}

/*

 * 设置选中的区域

 * 获得编辑框中的光标

 * 若光标没有高亮选区则将光标所在处的词作为选区

 * 将参数format所表示的格式应用到光标所在处的字符应用到选中区字符

*/

void ImageProcessor::mergeFormat (QTextCharFormat formt)

{

    QTextCursor cursor = showWidget->text->textCursor ();

    if(!cursor.hasSelection ())

    {

        cursor.select (QTextCursor::WordUnderCursor);

    }

    cursor.mergeCharFormat (formt);

    showWidget->text->mergeCurrentCharFormat (formt);

}

/*

 * 设置字号

 * 将参数format所表示的格式应用到光标所在处的字符应用到选中区字符

*/

void ImageProcessor::ShowSizeSpinBox(QString spinValue)

{

    QTextCharFormat fmt;

    fmt.setFontPointSize (spinValue.toFloat ());

    showWidget->text->mergeCurrentCharFormat (fmt);

}

/*

 * 设置粗体 QFont::Light(25) QFont::Normal(50) QFont::DemiBold(63) QFont::Bold(75) QFont::Black(87)

 * 通常在QFont::Bold(75) 和 QFont::Normal(50)之间交换

*/

void ImageProcessor::ShowBoldBtn()

{

    QTextCharFormat fmt;

    fmt.setFontWeight (boldBtn->isChecked () ? QFont::Bold : QFont::Normal);

    showWidget->text->mergeCurrentCharFormat (fmt);

}

/*

 * 设置文字显示斜体

*/

void ImageProcessor::ShowItalicBtn()

{

    QTextCharFormat fmt;

    fmt.setFontItalic (italicBtn->isChecked ());

    showWidget->text->mergeCurrentCharFormat (fmt);

}

/*

 * 设置文字加下划线

*/

void ImageProcessor::ShowUnderlineBtn()

{

    QTextCharFormat fmt;

    fmt.setFontUnderline (underlineBtn->isChecked ());

    showWidget->text->mergeCurrentCharFormat (fmt);

}

/*

 * 设置文字的颜色

 * QColor color = QColorDialog::getColor (Qt::blue, this);使用了标准颜色对话框的方式，

 * 当单击触发颜色按钮时，弹出标准颜色对话框选择颜色

 * color.isValid()可以判断用户选择颜色是否有效

*/

void ImageProcessor::ShowColorBtn()

{

    QColor color = QColorDialog::getColor (Qt::blue, this);

    if(color.isValid ())

    {

        QTextCharFormat fmt;

        fmt.setForeground (color);

        showWidget->text->mergeCurrentCharFormat (fmt);

    }

}

/*

 * 设置字符格式

*/

void ImageProcessor::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 ());

}

/*

 * 实现文本排序QTextCursor文本光标

 * 首先获取光标的指针

 * 设置光标处的风格

*/

void ImageProcessor::ShowList(int index)

{

    //获取编辑框的QTextCursor对象指针

    QTextCursor cursor = showWidget->text->textCursor ();

    if(index)

    {

        QTextListFormat::Style style = QTextListFormat::ListDisc;   //黑色实心圆点

        switch(index)

        {

        case 1:

            style = QTextListFormat::ListDisc; break;       //黑色实心圆点

        case 2:

            style = QTextListFormat::ListCircle; break;     //黑色空心圆点

        case 3:

            style = QTextListFormat::ListSquare; break;     //黑色实心方框

        case 4:

            style = QTextListFormat::ListDecimal; break;    //序列1.

        case 5:

            style = QTextListFormat::ListLowerAlpha; break; //序列a.

        case 6:

            style = QTextListFormat::ListUpperAlpha; break; //序列A.

        case 7:

            style = QTextListFormat::ListLowerRoman; break; //序列i.

        case 8:

            style = QTextListFormat::ListUpperRoman; break; //序列ii.

        default:

            break;

        }

        //设置缩进值

        cursor.beginEditBlock ();

        QTextBlockFormat blockFmt = cursor.blockFormat ();  //获得段落的缩进值

        QTextListFormat listFmt;                            //定义QTextListFormat的缩进值

        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);

    }

}

/*

 * 设置QTextEdit的当前段落的对齐调整

*/

void ImageProcessor::ShowAlignment(QAction *act)

{

    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);

}

/*

 * 响应文本光标位置处发生改变的信号

*/

void ImageProcessor::ShowCursorPositionChanged()

{

    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);

}

main.cpp

#include "imageprocessor.h"

#include <QApplication>

int main(int argc, char *argv[])

{

    QApplication a(argc, argv);

    ImageProcessor w;

    w.show();

    return a.exec();

}