Make the option to record samples more prominent by providing a pixmap
button that is always shown and that can be used to turn recording on or
off. The corresponding widget which constitutes of the button and a label
is always positioned at the bottom left of the sample clip.
Technical details
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The recording widget is built in the private method `buildRecordWidget`.
The method `adjustRecordWidget` is used to move the recording widget to
the correct position relative to the sample view. It is called after
construction and whenever the sample clip is resized (see `resizeEvent`).
Add the method `SampleClip::getRecordModel` so that the pixmap button can
be configured to act on it.
48c4dce96f