Use timer to update text in pushbutton?

Hello,

Is there a way for a pushbutton to change its text automatically after every 5 or so seconds? My plan is to use a matrix that will contain cells of words that will be displayed onto the pushbutton. For example it will start with the word " bent" then after five seconds, it will display " went". The changing text should not be dependent on the user pressing the button. If a pushbutton is not the way to go, then can you help me with what can work? I am very new to this whole GUI idea. Also, is it better to use GUIDE or write up my own code? Thank you.

Answer 1

[Geoff Hayes]

Justin - using GUIDE is a good way to start designing your interface. Its GUI editor allows you to drag and drop components on to the "canvas", and it provides you with many of the callbacks that you would need to respond to push button events, menu choices, etc.

For your project, you can easily use a timer to update the text of a push button or a static text control. Either would suit your needs but perhaps there is a reason why you want a push button to be used.

In the _OpeningFcn of your GUI, you could create your five second timer as

 handles.timer = timer('Name','MyTimer',               ...
                       'Period',5,                     ...
                       'StartDelay',0,                 ...
                       'TasksToExecute',inf,           ... 
                       'ExecutionMode','fixedSpacing', ...
                       'TimerFcn',{@timerCallback,hObject}); 

 % Update handles structure
 guidata(hObject, handles);

 % start the timer
 start(handles.timer);

We save the timer handle to the handles structure in the event that we need to access it at a later time. We then start the timer (it is stopped when the GUI is closed) and rely on its callback to fire every five seconds. We define the callback as

 function timerCallback(hTimer, eventdata, hFigure)

 handles = guidata(hFigure);
 str = handles.myCellData{handles.strIdx};
 set(handles.pushbutton1,'String',str);
 handles.strIdx = handles.strIdx + 1;
 if handles.strIdx > length(handles.myCellData)
    handles.strIdx = 1; 
 end
 guidata(hFigure,handles);

Note the third parameter is hFigure which is the hObject from the _OpeningFcn. We use this (GUI) handle so that we can get the handles structure which contains our cell string data, the current index for where we are in the cell array, and the handles to all GUI controls (of which the pushbutton is of interest to us). We get the string, update the button text, increment the counter, and save the updated handles structure.

See the attached for an example. Try it, and see what happens!

[Justin]

Thank you so much for your help. If you were wondering why I needed the push button, I needed the user to click the button and record when he or she clicked it. There will be multiple buttons with changing text, and the user needs to click on the right button with the right word. Do you know of any good tutorials or references to help me with this? Once again, thank you for your help with the timer!

[Geoff Hayes]

That's interesting, Justin! As for good tutorials or references, I would use this site, or the File Exchange.

[Justin]

Hi,

I've been working off of your example and its been a great help. One thing that I do not get is what hTimer and hFigure does in:

function timerCallback(hTimer, eventdata, hFigure)

Thank you.

[Geoff Hayes]

hTimer is the handle to the timer object that the callback, timerCallback, is associated with. (It is unused in the callback.)

hFigure is the handle to the figure (your GUI) which we can use to get the handles structure via

 handles = guidata(hFigure);