Painting problem

[Mel]

Marcel,

Thanks for your patience.

I get no errors when running the last piece of code I sent; it just doesn't paint. I printed out this->width() and this->height just before the call to eraseRect, and it shows the size of pbs to be (2, 109, 644, 15). I removed the line that was clearly out of the print area, compiled, and ran it again. Still no painting.

WRT the size of the widgets, I would think that's set in updateLayout(). I didn't write the original code, so I'm not sure why the author chose to implement it that way.

I'll have many changes in arithmetic to make in the program, but I feel that if I can get the toy I posted to run I'll be able to conquer the rest.

Thanks.

Cheers,
Mel

[marcel]

Instead of drawing the lines try p.fillRect( rect(), Qt::red ) ;
See if anything is being painted now. Perhaps you need to set a width for the pen.

regards

[Mel]

Marcel,

p.fillRect( rect(), Qt::red ) ;

filled pbs with a bright red.

The pen width is set to 0, so a 1 pixel width line should be drawn.

I removed the background from pbs, but still no line.

Thus far the only thing I've been able to display on pbs is your fillRect suggestion.
I also tried
p.fillRect(4,115,34,6,Qt::red);
which should have filled a small rectangle, but nothing happened.

It's probably late in your area, but do you have any last suggestions for today?

Thanks again.

Cheers,
Mel

[marcel]

OK.
A painter draws in paint device (widget in this case ) local coordinates.
Meaning that when you used my previous suggestion, something got filled, but not the right thing .

Thus, everything must be drawn relative to (0,0).
Calling p.fillRect( 0, 0, size().width(), size().height(), Qt:red ) will fill the ENTIRE widget.
For what you were trying to achieve call p.fillRect( 0, 0, 30, 6, Qt:red ). This will fill a small rect in the top left corner of the widget.

To be sure just do a drawRect( 0, 0, size().width(), size().height() ) - draw a frame around the widget.

If this works ( and it will ), draw everything relative to (0, 0 ) - lines, etc.

It's probably late in your area, but do you have any last suggestions for today?

It's 11 PM, not so late.

Regards

[Mel]

Sigh ... Of course it's relative! I knew there was some fundamental point I was missing! I adjusted my numbers, and painted the rectangle and the line I was trying to paint.

I can't thank you enough for your help, Marcel. I have a lot of work still ahead, but your help has removed a big roadblock. I put my question out to this group, because they had advertised a 95% success rate in solving users' problems. Mine can certainly be added to the success list thanks to your efforts.

Thanks again for your time and patience.

Cheers,
Mel

[marcel]

Happy to be of some help!

Regards