Control image transparency with a slider- appDesigner

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Hi all,
I'm trying to control de tranparency of two images using a slider.
Currently, I don't know how to do the code for this feature with a callback function with the slider.
Can anybody help me?
What I wanted, for a better understanding, is that when I'm at a max value, I only see one of the images and at the min value I only see the other. Obviously, when I move the slider I want the transparency of them to change.
Thanks in advance
Adam on 15 Jul 2019
It would be easier if you post the relevant code you currently have. I don't really have time for long answers from scratch, hence me adding a comment rather than an 'Answer'

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Accepted Answer

Adam Danz
Adam Danz on 15 Jul 2019
Edited: Adam Danz on 10 Feb 2021
This should get you started.
Two images are plotted on top of each other. A slider is added that sets the AlphaData of the top image.
% Create a figure with two images overlayed
fig = uifigure('HandleVisibility','on');
[X,cmap] = imread('corn.tif');
hold on
[X2,map] = imread('peppers.png');
img2 = imshow(X2,map);
% Create a GUI with a slider that controls the 'AlphaData' value of the currently selected object
sld = uislider(fig,'Position',[50,50,300,3],'Value',1,'Limits',[0,1],...
'ValueChangingFcn', @(sld,event)changeTransparencyFcn(sld,event,img2),...
'BusyAction', 'cancel');
% set the slider properties such as position etc....
% %
function changeTransparencyFcn(~, event, hobj)
% hobj is the image object handle
set(hobj,'AlphaData', event.Value)
drawnow limitrate
Changes made to improve answer on Feb 9, 2021.
Adam Danz
Adam Danz on 27 Feb 2020
In my answer,
set(gco,'AlphaData', sld.Value)
the slider is controlling the AlphaData property values of the currently selected image.
The link I provided in my previous comment lists properties of images. I don't know what you define as "sensitivity". If you can't figure that out, it might be better to post a new questions since I have limited time right now (feel free to link to this answer).

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