QT turorial 5 by Derek Banas

// add the following includes.
#include <QInputDialog>

#include <QDir>
#include <QFileDialog>
#include <QColorDialog>

#include <QMessageBox>

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

    scribbleArea = new ScribbleArea;
    //ui->centralWidget(scriblearea);
    setCentralWidget(scribbleArea);
    //ui->MainWindow::


    createActions();
    createMenus();
    setWindowTitle("scribble");
    resize(500,500);
}

Paint_App/mainwindow.cpp:20: error: 'scribbleArea' was not declared in this scope
     scribbleArea = new ScribbleArea;
     ^

Paint_App/mainwindow.cpp:49: error: 'scribbleArea' was not declared in this scope
         scribbleArea->openImage(fileName);
         ^
// void MainWindow::penColor(){
Paint_App/mainwindow.cpp:61: error: 'scribbleArea' was not declared in this scope
     QColor newColor = QColorDialog::getColor(scribbleArea->penColor());
                                              ^

// void MainWindow::penWidth(){
Paint_App/mainwindow.cpp:72: error: 'scribbleArea' was not declared in this scope
                                             scribbleArea->penWidth(),
                                             ^
// foreach (QByteArray format, QImageWriter::supportedImageFormats())
Paint_App/mainwindow.cpp:96: error: incomplete type 'QImageWriter' used in nested name specifier
     foreach (QByteArray format, QImageWriter::supportedImageFormats()) {
                                 ^
// connect(printAct, SIGNAL(triggered()), scribbleArea, SLOT(print()));
Paint_App/mainwindow.cpp:112: error: 'scribbleArea' was not declared in this scope
     connect(printAct, SIGNAL(triggered()), scribbleArea, SLOT(print()));

// bool MainWindow::saveFile(const QByteArray &fileFormat)                                         ^
Paint_App/mainwindow.cpp:210: error: 'scribbleArea' was not declared in this scope
         return scribbleArea->saveImage(fileName, fileFormat.constData());
                ^