How can we draw a customizable rectangular ROI on an axes using AppDesigner?

Hello,

I need to draw a customizable rectangular ROI on an axes in AppDesigner:

I tried this in AppDesigner:

h = drawrectangle(app.FullImageUIAxes, 'Position', [25,25,50,50], 'LineWidth', [2], 'Color', [1 0 0]);

But I get this error: ROI parent must be a valid Axes object.

I know the axes reference is correct.

Next I tried:

h = drawrectangle(app.FullImageUIAxes, 'Parent', app.UIFigure, 'Position', [25,25,50,50], 'LineWidth', [2], 'Color', [1 0 0]);

But I get the same error.

How should the axes be referenced when using drawrectangle in AppDesigner?

Answer 1

[Marc McLean]

App Designer errors if the axes is produced through the App Designer GUI. However, if the axes is produced programatically, App Designer finds the axes correctly. To produce the axes programatically, for example:

app.FullImageUIAxes = axes(app.UIFigure, 'Units', 'Pixels', 'Position',[166,84,750,744], 'XTick', [], 'YTick', []);

Then you can use drawrectangle:

app.ROI = drawrectangle(app.FullImageUIAxes, 'Position', [app.ROIposition(1),app.ROIposition(2),app.ROIposition(3),app.ROIposition(4)], 'LineWidth', [1], 'Color', [1 0 0]);

You have to add listeners programatically since you cannot add them through App Designer in this case:

addlistener(app.ROI,'MovingROI', @(varargin)ROIMoving(app, app.ROI));

[Guojin Feng]

Interesting. It does work when using codes to create the axes.

I have been willing to use such features in app designer.

Do you have an explanation about this? As I don't see the difference in creating the axes by coding or by App Designer GUI.

[Sean de Wolski]

It's an axes not a uiaxes. Only uiaxes can be added interactively.

[Guojin Feng]

I see. This makes sense then. Thanks for replying on this.

[Sean de Wolski]

It's worth noting that this answer was true for 18b and 19a. With 19b, uiaxes is supported natively.

Answer 2

[Sean de Wolski]

In 19b, this works on a uiaxes as well.

drawrectangle(uiaxes)

[Guojin Feng]

Excellent ! Great feature to have.