"H must be the handle to a figure or figure descendent" error using timers with a GUI

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Nope
Nope 2012-5-17
So I'm trying to make a threshold-crossing interval algorithm to detect ventricular fibrillation and wanted to make a few things (contained in the function "my_callback_function") happen every 1 second. I set up a timer with the line
handles.t=timer('TimerFcn', {@TCIfunc,handles.ecg},'ExecutionMode','FixedRate','Period',1,'StartDelay',1);
The "TCIfunc" function goes as follows:
function TCIfunc(hObject,eventdata,handles)
handles=guidata(handles);
handles.t1==handles.t3;
handles.t3==toc;
tic;
handles.t2_flag==0;
%start(handles.t);
handles.threshold==0.2*handles.max;
handles.max==0;
handles.N == 0;
guidata(handles.ecg, handles);
I declared t1 etc. using handles before creating the timer, in the opening function which includes the timer activation, seen here:
function ecg_OpeningFcn(hObject, eventdata, handles, varargin)
delete (instrfind)
handles.s = serial('COM11');
set(handles.s, 'InputBufferSize', 50); %number of bytes in input buffer
set(handles.s, 'FlowControl', 'none');
set(handles.s, 'BaudRate', 19200);
set(handles.s, 'Parity', 'none');
set(handles.s, 'DataBits',8);
set(handles.s, 'StopBits', 1);
set(handles.s, 'Timeout',1);
handles.threshold_flag=0;
handles.t2_flag=0;
handles.max=0;
handles.threshold=0;
handles.TCI_counter=0;
handles.N=0;
handles.t1=0;
handles.t2=0;
handles.t3=0;
handles.t4=0;
handles.ecg=gcf;
handles.t=timer('TimerFcn', {@TCIfunc,handles.ecg},'ExecutionMode','FixedRate','Period',1,'StartDelay',1);
guidata(handles.ecg,handles);
start(handles.t);
guidata(hObject, handles);
tic;
handles.output = hObject;
guidata(hObject, handles);
varargout{1} = handles.output;
But I keep getting the error: "Error while evaluating TimerFcn for timer 'timer-25'
H must be the handle to a figure or figure descendent." Anyone know what's going on? I'd be very grateful for any help. Full disclosure: I'm relatively new to MATLAB and don't have much idea what I'm doing.
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Nope
Nope 2012-5-17
Thanks, sorry about that. As you can see I've made a little bit of progress, but now I'm getting a different error message.

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回答（1 个）

Walter Roberson
Walter Roberson 2012-5-17
Please rename your "handles" parameter for your timer function to reflect that you are passing in a figure number rather than a handles structure. You will appreciate the change the next time you go to debug your code after not having looked at it for a day.
Then at the command window, put in
dbstop if error
and run again, and see what you get.
The statement,
handles.ecg=gcf;
Try using
handles.ecg = hObject;
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Nope
Nope 2012-5-17
I do tic in the routine that creates the timer, dunno what that message was about. As I said, it's back to the figure descendents one.

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