Purpose

Issue, with steps to reproduce: #537

There are several places in the code that use the pattern:

set(H,'pointer', 'watch');
% do stuff
set(H, 'pointer', 'arrow');

If there's an error in the middle, the pointer restore action is never reached, and the pointer gets stuck in the watch icon. The user gets the feeling that the app is still processing a command, but it is actually waiting for a new user action.

Approach

Replaced some (see note below) of these occurrences with the pattern:

set(H,'pointer', 'watch');
restore_object = onCleanup(@() set(H, 'pointer', 'arrow'));
% do stuff

The onCleanup hook is executed upon deletion of the restore_object, regardless of whether this is due to an error, or successful execution of the rest of the code in the scope.

Open Questions and Pre-Merge TODOs

• Use github checklists. When solved, check the box and explain the answer.

• Review that changed source files/lines are related to the pull request/issue
  If any files/commits were accidentally included, cherry-pick them into another branch.

• Review that changed source files/lines were not accidentally deleted
  Fix appropriately if so.

• Test new features or bug fix
  If not implemented/resolved adequately, solve it or inform the developer by requesting changes in your review.
  Preferably, set breakpoints in the locations that the code was changed and follow allong line by line to see if the code behaves as intended.

Manual GUI tests (general)

• Does the qMRLab GUI open?
• Can you change models?
• Can you load a data folder for a model?
• Can you view data?
• Can you zoom in the image?
• Can you pan out of the image?
• Can you view the histogram of the data?
• Can you change the color map?
• Can you fit dataset (Fit data)?
• Can you save/load the results?
• Can you open the options panel?
• Can you change option parameters?
• Can you save/load option paramters?
• Can you select a voxel?
• Can you fit the data of that voxel ("View data fit")?
• Can you simulate and fit a voxel ("Single Voxel Curve")?
• Can you run a Sensitivity Analysis?
• Can you simulate a Multi Voxel Distribution?

Specifications

• Version:
• Platform:
• Subsystem: