Problems with QPainter

[franco.amato]

Great. Try to fit it into those 30 lines. You don't even have to paint anything as you are getting errors before any painting is done - just initialize the painter.

Dear wysota. I solved the problem that gave the error. Is the line:

resize(wave->getSamples(), 200);

resize(wave->getSamples(), 200);

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This did that the waveWidget was expanded ( in the x direction ) more that the mainWindow because the number of audio samples I have is ~10E6.
So I tried to attach the waveWidget to a QScrollArea without success so:

CentralWidget::CentralWidget( QWidget* parent /* = 0 */ ) 
: QWidget(parent),
  mp_vBox( 0 ),
  mp_wave( 0 )
{
	/* vertical layout */
	mp_vBox = new QVBoxLayout( this );
	/* scroll area */
	scrollArea = new QScrollArea();
	/* waveform visualizer */
	mp_wave = new WaveWidget( this );
	scrollArea->setWidget( mp_wave );
	mp_vBox->addWidget( scrollArea );
	setLayout( mp_vBox );
}

CentralWidget::CentralWidget( QWidget* parent /* = 0 */ ) 
: QWidget(parent),
  mp_vBox( 0 ),
  mp_wave( 0 )
{
	/* vertical layout */
	mp_vBox = new QVBoxLayout( this );
	/* scroll area */
	scrollArea = new QScrollArea();
	/* waveform visualizer */
	mp_wave = new WaveWidget( this );
	scrollArea->setWidget( mp_wave );
	mp_vBox->addWidget( scrollArea );
	setLayout( mp_vBox );
}

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This did that now I can't see the waveWidget.
Where my code is wrong?

Best Regards

[wysota]

Call QScrollArea::setWidgetResizable() with true as the parameter and see if it helps. In general you should reimplement sizeHint() for your wave widget.