removeNewPositionCallback

Remove new-position callback from ROI object

removeNewPositionCallback is not recommended. With the new ROIs, use the addlistener object function instead. For more information, see Compatibility Considerations.

Syntax

removeNewPositionCallback(h,id)

Description

example

removeNewPositionCallback(h,id) removes the corresponding function from the new-position callback list of the ROI object, h.

Examples

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Add and Remove New Position Callback

Create a line ROI object. Display the position of the line in the title. Use addNewPositionCallback to update the title each time you move the line.

imshow("pout.tif")
h = imline(gca,[10 100],[100 100]);
id = addNewPositionCallback(h,@(pos) title(mat2str(pos,3)));

Move the line to observe the callback behavior.

After observing the callback behavior, remove the callback. The title no longer changes when you move the line.

removeNewPositionCallback(h,id);

Input Arguments

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`h` — ROI object
`imellipse` | `imline` | `impoint` | `impoly` | `imrect`

ROI object, specified as an imellipse, imline, impoint, impoly, or imrect object.

`id` — Identifier of new-position callback function
`struct`

Identifier of new-position callback function, specified as a struct.

Version History

Introduced in R2008a

expand all

R2018b: `removeNewPositionCallback` is not recommended

Starting in R2018b, a new set of ROI objects replaces the existing set of ROI objects. The new objects provide more functional capabilities, such as face color transparency. The new classes also support events that you can use to respond to changes in your ROI such as moving or being clicked. Although there are no plans to remove the old ROI objects at this time, switch to the new ROIs to take advantage of the additional capabilities and flexibility. For more information on creating ROIs using the new ROI functions, see Create ROI Shapes.

With the new ROIs, the Position property contains the current location of the ROI. To receive notification when this value changes, set up a listener using the addlistener object function. To remove this callback, delete the listener object.

Update Code

Update all instances of removeNewPositionCallback.

Discouraged Usage Recommended Replacement

Discouraged Usage	Recommended Replacement
This example uses the `addNewPositionCallback` method to specify a callback function to execute when the ROI changes position. The code then uses `removeNewPositionCallback` to remove the callback. imshow("cameraman.tif") h = imrect(gca, [10 10 100 100]); % Add callback that updates the title with position. id = addNewPositionCallback(h,@(p) title(mat2str(p,3))); % Remove position callback. Title no longer updates. removeNewPositionCallback(h,id);	Here is equivalent code, creating a new ROI object and replacing the `addNewPositionCallback` object function with the `addlistener` object function. This example listens for the `"MovingROI"` event. To remove the listener, use `delete(el)`. imshow("cameraman.tif") h = drawrectangle(gca,"Position",[10 10 100 100]); % Set up a listener for ROI moving events. el = addlistener(h,"MovingROI",@mymovecb) % Callback to update title with current position function mymovecb(src,evt) currpos = evt.CurrentPosition; title(mat2str(currpos,3)) end

This example uses the addNewPositionCallback method to specify a callback function to execute when the ROI changes position. The code then uses removeNewPositionCallback to remove the callback.

imshow("cameraman.tif")
h = imrect(gca, [10 10 100 100]);
% Add callback that updates the title with position.
id = addNewPositionCallback(h,@(p) title(mat2str(p,3)));
% Remove position callback. Title no longer updates.
removeNewPositionCallback(h,id);

Here is equivalent code, creating a new ROI object and replacing the addNewPositionCallback object function with the addlistener object function. This example listens for the "MovingROI" event. To remove the listener, use delete(el).

imshow("cameraman.tif")
h = drawrectangle(gca,"Position",[10 10 100 100]);
% Set up a listener for ROI moving events.
el = addlistener(h,"MovingROI",@mymovecb)
% Callback to update title with current position
function mymovecb(src,evt)
    currpos = evt.CurrentPosition;
    title(mat2str(currpos,3))
end

removeNewPositionCallback

Syntax

Description

Examples

Add and Remove New Position Callback

Input Arguments

`h` — ROI object
`imellipse` | `imline` | `impoint` | `impoly` | `imrect`

`id` — Identifier of new-position callback function
`struct`

Version History

R2018b: `removeNewPositionCallback` is not recommended

See Also

Topics

removeNewPositionCallback

Syntax

Description

Examples

Add and Remove New Position Callback

Input Arguments

h — ROI object imellipse | imline | impoint | impoly | imrect

id — Identifier of new-position callback function struct

Version History

R2018b: removeNewPositionCallback is not recommended

See Also

Topics

WeChat

`h` — ROI object
`imellipse` | `imline` | `impoint` | `impoly` | `imrect`

`id` — Identifier of new-position callback function
`struct`

R2018b: `removeNewPositionCallback` is not recommended