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# Picture

This example shows how to make a picture, store it to a file, and read it as a set of drawing commands.

Implementation:

    /****************************************************************************
    ** $Id: qt/picture.cpp   3.3.8   edited Jan 11 14:37 $
    **
    ** Copyright (C) 1992-2007 Trolltech ASA.  All rights reserved.
    **
    ** This file is part of an example program for TQt.  This example
    ** program may be used, distributed and modified without limitation.
    **
    *****************************************************************************/

    #include <ntqapplication.h>
    #include <ntqpainter.h>
    #include <ntqpicture.h>
    #include <ntqpixmap.h>
    #include <ntqwidget.h>
    #include <ntqmessagebox.h>
    #include <ntqfile.h>
    #include <ctype.h>

    void paintCar( TQPainter *p )                    // paint a car
    {
        TQPointArray a;
        TQBrush brush( TQt::yellow, TQt::SolidPattern );
        p->setBrush( brush );                       // use solid, yellow brush

        a.setPoints( 5, 50,50, 350,50, 450,120, 450,250, 50,250 );
        p->drawPolygon( a );                        // draw car body

        TQFont f( "courier", 12, TQFont::Bold );
        p->setFont( f );

        TQColor windowColor( 120, 120, 255 );        // a light blue color
        brush.setColor( windowColor );              // set this brush color
        p->setBrush( brush );                       // set brush
        p->drawRect( 80, 80, 250, 70 );             // car window
        p->drawText( 180, 80, 150, 70, TQt::AlignCenter, "--  TQt  --\nTrolltech AS" );

        TQPixmap pixmap;
        if ( pixmap.load("flag.bmp") )              // load and draw image
            p->drawPixmap( 100, 85, pixmap );

        p->setBackgroundMode( TQt::OpaqueMode );     // set opaque mode
        p->setBrush( TQt::DiagCrossPattern );        // black diagonal cross pattern
        p->drawEllipse( 90, 210, 80, 80 );          // back wheel
        p->setBrush( TQt::CrossPattern );            // black cross fill pattern
        p->drawEllipse( 310, 210, 80, 80 );         // front wheel
    }

    class PictureDisplay : public TQWidget           // picture display widget
    {
    public:
        PictureDisplay( const char *fileName );
       ~PictureDisplay();
    protected:
        void        paintEvent( TQPaintEvent * );
        void        keyPressEvent( TQKeyEvent * );
    private:
        TQPicture   *pict;
        TQString     name;
    };

    PictureDisplay::PictureDisplay( const char *fileName )
    {
        pict = new TQPicture;
        name = fileName;
        if ( !pict->load(fileName) ) {              // cannot load picture
            delete pict;
            pict = 0;
            name.sprintf( "Not able to load picture: %s", fileName );
        }
    }

    PictureDisplay::~PictureDisplay()
    {
        delete pict;
    }

    void PictureDisplay::paintEvent( TQPaintEvent * )
    {
        TQPainter paint( this );                     // paint widget
        if ( pict )
            paint.drawPicture( *pict );             // draw picture
        else
            paint.drawText( rect(), AlignCenter, name );
    }

    void PictureDisplay::keyPressEvent( TQKeyEvent *k )
    {
        switch ( tolower(k->ascii()) ) {
            case 'r':                               // reload
                pict->load( name );
                update();
                break;
            case 'q':                               // quit
                TQApplication::exit();
                break;
        }
    }

    int main( int argc, char **argv )
    {
        TQApplication a( argc, argv );               // TQApplication required!

        const char *fileName = "car.pic";           // default picture file name

        if ( argc == 2 )                            // use argument as file name
            fileName = argv[1];

        if ( !TQFile::exists(fileName) ) {
            TQPicture pict;                          // our picture
            TQPainter paint;                         // our painter

            paint.begin( &pict );                   // begin painting onto picture
            paintCar( &paint );                     // paint!
            paint.end();                            // painting done

            pict.save( fileName );                  // save picture
            TQMessageBox::information(0, "TQt Example - Picture", "Saved.  Run me again!");
            return 0;
        } else {
            PictureDisplay test( fileName );        // create picture display
            a.setMainWidget( &test);                // set main widget
            test.setCaption("TQt Example - Picture");
            test.show();                            // show it

            return a.exec();                        // start event loop
        }
    }

See also Examples.