使用Qt控件練習文本編輯窗口的創建。

#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>
#include <QLabel>
#include <QProgressBar>QT_BEGIN_NAMESPACE
namespace Ui {
class MainWindow;
}
QT_END_NAMESPACEclass MainWindow : public QMainWindow
{Q_OBJECTprivate:QLabel* m_labFile;QProgressBar* m_proGressBar;QLabel* m_labInfo;
public:MainWindow(QWidget *parent = nullptr);~MainWindow();private slots:void on_actionFile_New_triggered();void on_actionFile_Open_triggered();void on_actionFile_Save_triggered();void on_textEdit_copyAvailable(bool b);void on_textEdit_selectionChanged();void on_actionFont_Bold_triggered(bool checked);void on_actionFont_Italic_triggered(bool checked);void on_actionFont_UnderLine_triggered(bool checked);void on_fontSize_changed(int fontSize);void on_font_changed(QFont font);private:Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QActionGroup>
#include <QSpinBox>
#include <QFontComboBox>
#include <QProgressBar>MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);QActionGroup* action_group = new QActionGroup(this);action_group->addAction(ui->actionLang_Chinese);action_group->addAction(ui->actionLang_English);action_group->setExclusive(true);QSpinBox* spinFontSize = new QSpinBox(this);spinFontSize->setMaximum(50);spinFontSize->setMinimum(5);spinFontSize->setValue(ui->textEdit->font().pointSize());spinFontSize->setMinimumWidth(50);ui->toolBar->addWidget(spinFontSize);QFontComboBox* comboFontBox = new QFontComboBox;comboFontBox->setMinimumWidth(150);comboFontBox->setFont(ui->textEdit->font());ui->toolBar->addWidget(comboFontBox);ui->toolBar->addSeparator();ui->toolBar->addAction(ui->actionClose);m_labFile = new QLabel(this);m_labFile->setMinimumWidth(150);m_labFile->setText("文件名: ");ui->statusbar->addWidget(m_labFile);m_proGressBar = new QProgressBar(this);m_proGressBar->setMinimum(5);m_proGressBar->setMaximum(50);m_proGressBar->setValue(ui->textEdit->font().pointSize());ui->statusbar->addWidget(m_proGressBar);m_labInfo = new QLabel("PermanentWidget");ui->statusbar->addPermanentWidget(m_labInfo);connect(spinFontSize, &QSpinBox::valueChanged, this, &MainWindow::on_fontSize_changed);connect(comboFontBox, &QFontComboBox::currentFontChanged, this, &::MainWindow::on_font_changed);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::on_actionFile_New_triggered()
{ui->textEdit->clear();ui->textEdit->document()->setModified(false);m_labFile->setText("文件名：新建一個文件");
}void MainWindow::on_actionFile_Open_triggered()
{m_labFile->setText("正在打開一個文件");
}void MainWindow::on_actionFile_Save_triggered()
{ui->textEdit->document()->setModified(false);m_labFile->setText("已經保存一個文件");
}void MainWindow::on_textEdit_copyAvailable(bool b)
{ui->actionEdit_Copy->setEnabled(b);ui->actionEdit_Cut->setEnabled(b);ui->actionEdit_Paste->setEnabled(ui->textEdit->canPaste());
}void MainWindow::on_textEdit_selectionChanged()
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();ui->actionFont_Bold->setChecked(fmt.font().bold());ui->actionFont_Italic->setChecked(fmt.font().italic());ui->actionFont_UnderLine->setChecked(fmt.font().underline());
}void MainWindow::on_actionFont_Bold_triggered(bool checked)
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();if(checked)fmt.setFontWeight(QFont::Bold);elsefmt.setFontWeight(QFont::Normal);//fmt.font().setBold(checked);ui->textEdit->setCurrentCharFormat(fmt);
}void MainWindow::on_actionFont_Italic_triggered(bool checked)
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();// fmt.font().setItalic(checked);fmt.setFontItalic(checked);ui->textEdit->setCurrentCharFormat(fmt);
}void MainWindow::on_actionFont_UnderLine_triggered(bool checked)
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();// fmt.font().setUnderline(checked);fmt.setFontUnderline(checked);ui->textEdit->setCurrentCharFormat(fmt);
}void MainWindow::on_fontSize_changed(int fontSize)
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();fmt.setFontPointSize(fontSize);ui->textEdit->setCurrentCharFormat(fmt);m_proGressBar->setValue(fontSize);
}void MainWindow::on_font_changed(QFont font)
{QTextCharFormat fmt = ui->textEdit->currentCharFormat();fmt.setFont(font);ui->textEdit->setCurrentCharFormat(fmt);m_labInfo->setText("字體名稱 " + font.family());
}

#include "mainwindow.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}