Qt5實(shí)現(xiàn)文本編輯器(附詳細(xì)代碼)

更新時(shí)間：2021年07月05日 10:42:08 作者：進(jìn)擊的汪sir

QT是一個(gè)跨平臺(tái)的GUI開(kāi)發(fā)框架，我使用的QT5 C++版本的，本文主要介紹了Qt5實(shí)現(xiàn)文本編輯器，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

1. 功能介紹

老規(guī)矩，我們直接上截圖

這是主界面

文件菜單界面

編輯菜單界面

設(shè)置菜單界面

關(guān)于菜單界面

2. 功能演示

設(shè)置字體顏色

設(shè)置字體大小

點(diǎn)擊關(guān)于菜單

點(diǎn)擊關(guān)于Qt菜單

會(huì)自動(dòng)跳轉(zhuǎn)到Qt的官網(wǎng)

點(diǎn)擊圖片轉(zhuǎn)PDF

打開(kāi)文件等對(duì)話框

3. 代碼

我們直接上代碼

aboutwidget.h

#ifndef ABOUTWIDGET_H
#define ABOUTWIDGET_H

#include <QWidget>

namespace Ui {
class AboutWidget;
}

class AboutWidget : public QWidget
{
    Q_OBJECT

public:
    explicit AboutWidget(QWidget *parent = nullptr);
    ~AboutWidget();

private:
    Ui::AboutWidget *ui;
};

#endif // ABOUTWIDGET_H

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QFont>
#include <QColor>


QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();




private slots:
    void on_actionexit_triggered();

    void on_actioncolor_triggered();

    void on_actionfont_triggered();

    void on_actionne_triggered();

    void on_actionopen_triggered();

    void on_actionsave_triggered();

    void on_actionasfile_triggered();

    void on_actioncut_triggered();

    void on_actioncopy_triggered();

    void on_actionundo_triggered();

    void on_actionredo_triggered();

    void on_actionpatse_triggered();

    void on_actionAbout_triggered();

    void on_actionAboutQT_triggered();

    void on_actionPDF_triggered();

private:
    Ui::MainWindow *ui;
    QFont font;
    QColor color;
    QString currentFile;
};
#endif // MAINWINDOW_H

topdf.h

#ifndef TOPDF_H
#define TOPDF_H

#include <QWidget>

namespace Ui {
class ToPdf;
}

class ToPdf : public QWidget
{
    Q_OBJECT

public:
    explicit ToPdf(QWidget *parent = nullptr);
    ~ToPdf();
    bool pictureToPDF(QString sourth,QString sDir);

private slots:
    void on_pictureBtn_clicked();

    void on_saveBtn_clicked();

    void on_startBtn_clicked();

private:
    Ui::ToPdf *ui;
};

#endif // TOPDF_H

aboutwidget.cpp

#include "aboutwidget.h"
#include "ui_aboutwidget.h"

AboutWidget::AboutWidget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::AboutWidget)
{
    ui->setupUi(this);

    ui->Pixmap->setPixmap(QPixmap(":/dog.jpg").scaled(141,131,Qt::KeepAspectRatio));
}

AboutWidget::~AboutWidget()
{
    delete ui;
}

main.cpp

#include "mainwindow.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    w.show();
    return a.exec();
}

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QFontDialog>
#include <QColorDialog>
#include <QFile>
#include <QFileDialog>
#include <QMessageBox>
#include <QTextStream>
#include <QTextCodec>
#include <QDesktopServices>
#include "aboutwidget.h"
#include "topdf.h"
// #pragma execution_character_set("utf-8")
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);


    // 設(shè)置文本框?yàn)閱喂ぷ鲄^(qū)
    setCentralWidget(ui->textEdit);

    font = QFont("宋體",18,QFont::Normal,true);
    color = QColor(Qt::black);

    // 工具條，項(xiàng)目默認(rèn)生成一個(gè)
    // 工具條上放的是菜單常用的菜單項(xiàng)
    // 所以工具條和菜單共用QAction，得通過(guò)代碼添加
    ui->toolBar->addAction(ui->actionne);
    ui->toolBar->addAction(ui->actionopen);
    ui->toolBar->addAction(ui->actionsave);
    ui->toolBar->addAction(ui->actionPDF);
    ui->toolBar->addAction(ui->actionundo);
    ui->toolBar->addAction(ui->actionredo);
    ui->toolBar->addAction(ui->actioncopy);
    ui->toolBar->addAction(ui->actionpatse);
    ui->toolBar->addAction(ui->actioncolor);
    ui->toolBar->addAction(ui->actionfont);
    ui->toolBar->addAction(ui->actioncut);
    ui->toolBar->addSeparator();
    ui->toolBar->addAction(ui->actionexit);




}

MainWindow::~MainWindow()
{
    delete ui;
}


void MainWindow::on_actionexit_triggered()
{
    close();
}


void MainWindow::on_actioncolor_triggered()
{
    QColor c = QColorDialog::getColor(color,this,"顏色選擇框");
    if(c.isValid()){
        color = c;

        // 設(shè)置文本框的文本顏色
        // 1. 從光標(biāo)開(kāi)始新輸入的文本顏色被設(shè)置
        // 2. 鼠標(biāo)選中的文本顏色設(shè)置
        ui->textEdit->setTextColor(c);
    }
}

void MainWindow::on_actionfont_triggered()
{
    bool ok; // 用戶字體對(duì)話框保存是否選擇了字體的結(jié)構(gòu)

    // 第一個(gè)參數(shù)是判斷用戶是否選擇了字體，第二個(gè)是字體對(duì)話框的初始值
    QFont f = QFontDialog::getFont(&ok,font,this,"選擇文本框要設(shè)置的字體");

    if(ok){
        font = f;

        // 1. 從當(dāng)前光標(biāo)開(kāi)始
        // 2. 鼠標(biāo)選中的文本的字體
        ui->textEdit->setCurrentFont(f);
    }

}

void MainWindow::on_actionne_triggered()
{
    QMessageBox::warning(this,tr("Warning"),
    tr("創(chuàng)建新文件？"),
    QMessageBox::Yes | QMessageBox::Default,
    QMessageBox::No);

    currentFile.clear();
    ui->textEdit->setText(QString());

}

void MainWindow::on_actionopen_triggered()
{
    QString fileName = QFileDialog::getOpenFileName(this, "打開(kāi)文件");
    QFile file(fileName);
    currentFile = fileName;
    if (!file.open(QIODevice::ReadOnly | QFile::Text)) {
        QMessageBox::warning(this, "警告", "無(wú)法打開(kāi)文件: " + file.errorString());
        return;
     }
     setWindowTitle(fileName);
     QTextStream *in = new QTextStream(&file);
     in->setCodec("UTF-8");
     QString text = in->readAll();

     ui->textEdit->setText(text);
     delete in;
     file.close();
}

void MainWindow::on_actionsave_triggered()
{
    QString fileName;
    // 若沒(méi)有文件,重新創(chuàng)建一個(gè)
    if (currentFile.isEmpty()) {
        fileName = QFileDialog::getSaveFileName(this, "Save");
        currentFile = fileName;
    } else {
        fileName = currentFile;
    }

    // 打開(kāi)文件
    QFile file(fileName);
    if (!file.open(QIODevice::WriteOnly | QFile::Text)) {
        QMessageBox::warning(this, "警告", "無(wú)法打開(kāi)文件: " + file.errorString());
        return;
    }
    setWindowTitle(fileName);
    QTextStream out(&file);

    out.setCodec("UTF-8");

    QString text = ui->textEdit->toPlainText();
    out << text;
    file.close();

}

void MainWindow::on_actionasfile_triggered()
{
    QString fileName = QFileDialog::getSaveFileName(this, "另存為");
    QFile file(fileName);

    if (!file.open(QFile::WriteOnly | QFile::Text)) {
        QMessageBox::warning(this, "警告", "無(wú)法打開(kāi)文件: " + file.errorString());
        return;
    }
    currentFile = fileName;
    setWindowTitle(fileName);
    QTextStream out(&file);
    QString text = ui->textEdit->toPlainText();
    out << text;
    file.close();

}

void MainWindow::on_actioncut_triggered()
{
    ui->textEdit->cut();
}

void MainWindow::on_actioncopy_triggered()
{
    ui->textEdit->copy();
}


void MainWindow::on_actionundo_triggered()
{
    ui->textEdit->undo();
}

void MainWindow::on_actionredo_triggered()
{
    ui->textEdit->redo();
}

void MainWindow::on_actionpatse_triggered()
{
    ui->textEdit->paste();
}

void MainWindow::on_actionAbout_triggered()
{
    static AboutWidget about;
    about.show();
}

void MainWindow::on_actionAboutQT_triggered()
{
    QDesktopServices::openUrl(QUrl(QLatin1String("https://www.qt.io/zh-cn/")));
}

void MainWindow::on_actionPDF_triggered()
{
    static ToPdf pdf;
    pdf.show();
}

topdf.cpp

#include "topdf.h"
#include "ui_topdf.h"

#include <QFileDialog>
#include <QMessageBox>
#include <QPainter>
#include <QtPrintSupport/QPrinter>
ToPdf::ToPdf(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::ToPdf)
{
    ui->setupUi(this);
}

ToPdf::~ToPdf()
{
    delete ui;
}

bool ToPdf::pictureToPDF(QString sourth, QString sDir)
{

    try
    {
        QPixmap pixmap(sourth);
        //圖片生成pdf
        QPrinter printerPixmap(QPrinter::HighResolution);
        printerPixmap.setPageSize(QPrinter::Custom);  //設(shè)置紙張大小為A4
        printerPixmap.setOutputFormat(QPrinter::PdfFormat);  //設(shè)置輸出格式為pdf
        printerPixmap.setOutputFileName(sDir);   //設(shè)置輸出路徑

        double dHeight = 300;
        double dWidth = (double)pixmap.width() / (double)pixmap.height() * dHeight;
        printerPixmap.setPageSizeMM(QSize(dWidth, dHeight));
        printerPixmap.setPageMargins(0, 0, 0, 0, QPrinter::DevicePixel);

        QPainter painterPixmap;
        painterPixmap.begin(&printerPixmap);
        QRect rect = painterPixmap.viewport();
        float multiple = (double(rect.width()) / pixmap.width());
        float yMultiple = (double(rect.height()) / pixmap.height());
        float fMin = (multiple < yMultiple) ? multiple : yMultiple;
        painterPixmap.scale(fMin, fMin); //將圖像(所有要畫的東西)在pdf上放大multiple-1倍
        painterPixmap.drawPixmap(0, 0, pixmap.width(), pixmap.height(), pixmap);  //畫圖
        painterPixmap.end();

        return true;
    }
    catch (...)
    {
        return false;
    }


}

void ToPdf::on_pictureBtn_clicked()
{
    //定義文件對(duì)話框類
    QFileDialog *fileDialog = new QFileDialog(this);
    //定義文件對(duì)話框標(biāo)題
    fileDialog->setWindowTitle(tr("選擇圖片"));

    //設(shè)置默認(rèn)文件路徑
    //fileDialog->setDirectory(".");

    //設(shè)置文件過(guò)濾器
    fileDialog->setNameFilter(tr("Images(*.png *.jpg *.jpeg *.bmp)"));
    //設(shè)置可以選擇多個(gè)文件,默認(rèn)為只能選擇一個(gè)文件QFileDialog::ExistingFiles
    //fileDialog->setFileMode(QFileDialog::ExistingFiles);
    //設(shè)置視圖模式
    fileDialog->setViewMode(QFileDialog::Detail);
    //打印所有選擇的文件的路徑

    // 獲取選擇的文件名
    QStringList fileNameList;

    // exec()模態(tài)對(duì)話框
    if(fileDialog->exec()){

        fileNameList = fileDialog->selectedFiles();
    }
    ui->pictureFileName->setText(fileNameList[0]);
    //emit fileName(fileNameList);
}

void ToPdf::on_saveBtn_clicked()
{
    //定義文件對(duì)話框類
    QFileDialog *fileDialog = new QFileDialog(this);
    //定義文件對(duì)話框標(biāo)題
    fileDialog->setWindowTitle(tr("選擇PDF"));
    fileDialog->setViewMode(QFileDialog::Detail);
    //打印所有選擇的文件的路徑

    //設(shè)置文件過(guò)濾器
    fileDialog->setNameFilter(tr("*.pdf"));
    // 獲取選擇的文件名
    QStringList fileNameList;

    // exec()模態(tài)對(duì)話框
    if(fileDialog->exec()){

        fileNameList = fileDialog->selectedFiles();
    }

    ui->saveFileName->setText(fileNameList[0]);

}

void ToPdf::on_startBtn_clicked()
{
    QString picture = ui->pictureFileName->text();
    QString pdf = ui->pictureFileName->text();

    if(pictureToPDF(picture,pdf)){
        QMessageBox::information(this,"轉(zhuǎn)換成功","轉(zhuǎn)換成功?。。?);
    }else{
        QMessageBox::information(this,"轉(zhuǎn)換失敗","轉(zhuǎn)換失?。?);

    }
}