Xlib tutorial 2 - Events and errors

Author: Frederik Holljen

Publishing date: 04.02.2003 17:36

enum buttonState { NORMAL, HOVER, PRESSED };
void paintButton( Display *dpy, Painter *p, Window button, buttonState state = NORMAL )
{
    XWindowAttributes attr;
    // fetch window size
    XGetWindowAttributes( dpy, button, &attr );
    if( state == NORMAL )
        p->setForeground( "gray" );
    else
        p->setForeground( "darkgray" );

    p->drawRectangle( button, 0, 0, attr.width, attr.height, true );

    p->setForeground( "red" );
    p->drawRectangle( button, 0, 0, attr.width -1, attr.height -1, false );

    // draw the button text
    const char *text = "Quit";

    // fetch the Font from the painter
    const FFont *font = p->font();
    // fetch the height of the font, and the width of the text.
    int fontHeight = font->fontHeight(); // max height above and below baseline
    int textWidth = font->textWidth( text );
    
    // center the text at the top of the window
    p->setForeground( "black" );
    if( state == PRESSED )
        p->drawText( button, 2 + (attr.width - textWidth)/2, 2 + (attr.height + fontHeight)/2, text );
    else
        p->drawText( button, (attr.width - textWidth)/2, (attr.height + fontHeight)/2, text );
        
}