Any way to disable the whole plot (gray-out)?

[Uwe]

"plot->setEnabled( false );" should be fine, but you need to assign a palette to the plot canvas, where the brush is different for QColorGroup::Disabled.

QPalette pal;
pal.setBrush( QPalette::Window, Qt::blue );
pal.setBrush( QPalette::Disabled, QPalette::Window, Qt::gray );
plot->canvas()->setPalette( pal );

QPalette pal;
pal.setBrush( QPalette::Window, Qt::blue );
pal.setBrush( QPalette::Disabled, QPalette::Window, Qt::gray );
plot->canvas()->setPalette( pal );

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Uwe