Been writing a notepad clone with QT6 c++, but every time I save the file, it creates the file empty without the text from TextEdit;

Question

So I am writing the code for a notepad clone which I hope would evolve into a final draft clone in further updates, and I am using it as a tool to learn C++ and QT as I am still Quite a beginner with the langauge.

I have implemented a save function into the application, which when pressed should take the text written in the Textedit widget and write it into a file, but what seems to happen is that when I call that function it creates said file but leaves it empty without adding the text into it

this is my code


void MainWindow::on_actionSave_as_triggered()
{
    QString File_name = QFileDialog::getSaveFileName(this, "Save File as");
    QFile File(File_name);
    if(!File.open(QIODevice::WriteOnly) | QFile::Text) {
        QMessageBox::warning(this, "Save warning", "Error: File Did not save properly" + File.errorString());
        return;
    }
    current_file = File_name;
    setWindowTitle(File_name);
    QTextStream out(&File);
    QString writing = ui->textEdit->toPlainText();
    out << writing;
    File.flush();
    File.close();
}

here is the entire cpp file:

#include "mainwindow.h"
#include "./ui_mainwindow.h"
#include <iostream>
#include <stream>

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

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


void MainWindow::on_actionNew_triggered()
{
    current_file.clear();
    ui->textEdit->setText(QString());
}


void MainWindow::on_actionSave_triggered()
{


}


void MainWindow::on_actionOpen_triggered()
{
QString File_name = QFileDialog::getOpenFileName(this, "Open the 
File");
 QFile File(File_name);
 current_file = File_name;
 if(!File.open(QIODevice::ReadOnly | QFile::Text)){
     QMessageBox::warning(this,"warning", "Error, File Could not 
open");
     return;
 }
 setWindowTitle(File_name);
 QTextStream in(&File);
 QString Writing = in.readAll();
 ui->textEdit->setText(Writing);
 File.close();
}


void MainWindow::on_actionSave_as_triggered()
{
    QString File_name = QFileDialog::getSaveFileName(this, "Save File as");
    QFile File(File_name);
    if(File.open(QFile::WriteOnly | QFile::Text)) {
        QMessageBox::warning(this, "Save warning", "Error: File Did not save properly" + File.errorString());
        return;
    }
    current_file = File_name;
    setWindowTitle(File_name);
    QTextStream out(&File);
    QString writing = ui->textEdit->toPlainText();
    out << writing;
    File.flush();
    File.close();
}

edit: Tried removing, File.flush and .close but I still get the unknown error

Is `File.open(QIODevice::WriteOnly) | QFile::Text` what you meant to write? — Alan Birtles, Aug 11 '23 at 21:51
I don't think so, I added the "!" because I wanted to print out the error if the file does not open — Zayn Mady, Aug 11 '23 at 21:58
Does this answer your question? [How to fix QFile open error (unknown error) even the file exists?](https://stackoverflow.com/questions/54464877/how-to-fix-qfile-open-error-unknown-error-even-the-file-exists) — Abderrahmene Rayene Mihoub, Aug 11 '23 at 22:05
Then please share a [minimal **reproducible** example](https://stackoverflow.com/help/minimal-reproducible-example), because what you provided works when that typo is fixed. — Abderrahmene Rayene Mihoub, Aug 11 '23 at 22:16
I shared the rest of my code if that would help find the bug — Zayn Mady, Aug 11 '23 at 22:32
Your condition is wrong again, put `!` back, unknown error because there is no error. — Abderrahmene Rayene Mihoub, Aug 11 '23 at 22:37
oh I didn't see that typo at all! that solved it! thank youu — Zayn Mady, Aug 11 '23 at 22:39

score 0 · Answer 1 · answered Aug 11 '23 at 22:24

0

I think you need

out.flush();

instead of

File.flush();

(or just drop it altogether).

And you don't need File.close(), it is automatic for files.

The way you've coded it, the file gets closed before the QTextStream writes data to it.

answered Aug 11 '23 at 22:24

jpalecek

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Been writing a notepad clone with QT6 c++, but every time I save the file, it creates the file empty without the text from TextEdit;

1 Answers1