Help understand: Passing a function handle to another function as an argument
2 views (last 30 days)
Show older comments
set(S.fh,'windowbuttonmotionfcn',{@fh_wbmfcn,S})
I know @ is a handle to a separately defined function called fh_wbmfcn, but am puzzled about what the {} brackets are doing. Are they passing in S as an input to fh_wbmfcn? I have never seen this syntax before and it is hard to search the documentation for characters like @ or {}.
0 Comments
Accepted Answer
Walter Roberson
on 9 Jun 2017
Remember that every graphics callback is automatically passed two initial arguments: the source and the event data. Using the cell array {@fh_wbmfcn,S} has the same effect as if you had specified @(src,event) fh_wbmfcn(src, event, S)
3 Comments
Walter Roberson
on 9 Jun 2017
"Is it possible to pass the output arguments of fh_wbmfcn which are Cx, Cy to the workplace of function that calls it"
Sorry, no, callbacks are never invoked with output assigned. Callbacks are executed as if called from the base workspace, because they are invoked asynchronously. Functions do not call callbacks (but functions might define callbacks.)
More Answers (0)
See Also
Categories
Find more on Interactive Control and Callbacks in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!