qt 5.x　初探(1)

2017-05-14 · 1 min read · qt c++

嘛。。为了系统安全课来学一波qt...

现在算是写出了一个可以打开文件，保存文件的记事本。。。

接下来要搞定的事情是。。。如何写一个自定义的事件。。。比如计算个开方之类的。。。

放一波代码好了。。。

1#include <QAction>
2#include <QMenuBar>
3#include <QMessageBox>
4#include <QStatusBar>
5#include <QToolBar>
6#include <QDebug>
7#include <QTextEdit>
8#include <QFileDialog>

#include "mainwindow.h"

1MainWindow::MainWindow(QWidget *parent) :
2    QMainWindow(parent)
3{

1    openAction = new QAction(QIcon(":/images/file-open"), tr("&Open..."), this);
2    openAction->setShortcuts(QKeySequence::Open);
3    openAction->setStatusTip(tr("Open an existing file"));

1    saveAction = new QAction(QIcon(":/images/file-open"), tr("&Save..."), this);
2    saveAction->setShortcuts(QKeySequence::Save);
3    saveAction->setStatusTip(tr("Save a new file"));

1    QMenu *file = menuBar()->addMenu(tr("&File"));
2    file->addAction(openAction);
3    file->addAction(saveAction);

1    QToolBar *toolBar = addToolBar(tr("&File"));
2    toolBar->addAction(openAction);
3    toolBar->addAction(saveAction);

    textEdit = new QTextEdit(this);
    setCentralWidget(textEdit);

    connect(openAction, &QAction::triggered, this, &MainWindow::openFile);
    connect(saveAction, &QAction::triggered, this, &MainWindow::saveFile);


}

1MainWindow::~MainWindow()
2{
3}

 1void MainWindow::openFile()
 2{
 3    QString path = QFileDialog::getOpenFileName(this,
 4                                                tr("Open File"),
 5                                                ".",
 6                                                tr("Text Files(*.txt)"));
 7    if(!path.isEmpty()) {
 8        QFile file(path);
 9        if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
10            QMessageBox::warning(this, tr("Read File"),
11                                 tr("Cannot open file:\n%1").arg(path));
12            return;
13        }
14        QTextStream in(&file);
15        textEdit->setText(in.readAll());
16        file.close();
17    } else {
18        QMessageBox::warning(this, tr("Path"),
19                             tr("You did not select any file."));
20    }
21}

 1void MainWindow::saveFile()
 2{
 3    QString path = QFileDialog::getSaveFileName(this,
 4                                                tr("Open File"),
 5                                                ".",
 6                                                tr("Text Files(*.txt)"));
 7    if(!path.isEmpty()) {
 8        QFile file(path);
 9        if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
10            QMessageBox::warning(this, tr("Write File"),
11                                       tr("Cannot open file:\n%1").arg(path));
12            return;
13        }
14        QTextStream out(&file);
15        out << textEdit->toPlainText();
16        file.close();
17    } else {
18        QMessageBox::warning(this, tr("Path"),
19                             tr("You did not select any file."));
20    }
21}

1#include "mainwindow.h"
2#include <QApplication>
3#include <QSpinBox>
4#include <QSlider>
5#include <QHBoxLayout>

// !!! Qt 5

1int main(int argc, char *argv[])
2{
3    QApplication app(argc, argv);

    MainWindow win;
    win.show();

    return app.exec();
}





#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QTextEdit>

1namespace Ui {
2class MainWindow;
3}

1class MainWindow : public QMainWindow
2{
3    Q_OBJECT

1public:
2     MainWindow(QWidget *parent = 0);
3    ~MainWindow();

1private:
2    Ui::MainWindow *ui;
3    void openFile();
4    void saveFile();
5    QAction *openAction;
6    QAction *saveAction;
7    QTextEdit *textEdit;
8};

#endif // MAINWINDOW_H

大概看了一下午。。。这东西看起来虽然说完全没难度。。。但是还是很麻烦啊。。。

代码

qt 5.x 初探(1)

qt 5.x　初探(1)