QT27 how to read text file and display file to a textbrowser or textedit

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QFile>
#include <QTextStream>
#include <QDebug>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);

QFile file("C:/AdwCleaner/AdwCleaner[S1].txt");
if(!file.open(QIODevice::ReadOnly))
qDebug() << "open error";
QTextStream in(&file);
ui->textBrowser->setText(in.readAll());
}

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