1. Electrical and Computer Engineering Department SUNY – New Paltz
Computer Simulation
“Lecture 11”
Electrical and Computer Engineering Department
SUNY – New Paltz
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2. Analysis of GUI Objects
mygui.m
mygui.fig
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3. Graphical User Interfaces (GUIs)
Objectives
• figure files;
• application M-files;
• callback functions.
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4. Basic structure of a GUI
GUIDE:
Graphical User Interface Development Environment
GUIDE:
generates 2 files : FIG-file and application M-file
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5. Basic structure of a GUI
FIG-file contains a complete description of the GUI figure
application M-file contains the functions required to launch and control the GUI.
Callback functions, written by you, determine the action taken when you interact with a GUI component
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6. GUIDE
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7. Inspect Properties String property
Tag property of the button is set to pushbutton1
Callback property
myapp(’mybutton_Callback’,gcbo,[],guidata(gcbo))
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8. My First GUI! Click on the run arrow
In ‘mygui1.m’ file in the editor window,
Find function:
pushbutton1_Callback(hObject, eventdata, handles)
In that function, change the ‘String’ property of the object to ‘Hello GUI!’ by adding:
set(hObject, ‘String’, ‘Hello GUI!’)
set(handles.push_button1, ‘String’, ‘Hello GUI’)
Run the program
In Command Window: Type ‘guide’
Select ‘Create New Guide’
Call your fig file ‘mygui1.fig’
Adjust the window size to a smaller one
Drag a ‘pushbutton’ to the center
Double click on it and find ‘String’ property. Rename it ‘Click Me!’
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9. getting the time
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10. One Object affecting the other
Place 2 push buttons on the scree
Clicking the LHS button should change the background color of the RHS button Green.
Clicking the RHS button should clear(back to the default the Green color.
Hint use : Set(handles.pushbutton2, ..) to address the RHS button from the LHS call-back.
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11. Digital Clock
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12. Matlab Code % get time d = clock; % convert time to string
time = sprintf( ’%02.0f:%02.0f:%02.0f’,d(4),d(5),d(6));
% change the String property of pushbutton1
set(gcbo,’String’,time)
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13. Square Root GUI
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14. MATLAB Code
function varargout = pushbutton1_Callback(h, eventdata, handles, varargin)
% Stub for Callback of the uicontrol handles.pushbutton1.
a = str2num(get(handles.edit1,’String’));
x = a; % initial guess
for i = 1:8
x = (x + a/x)/2;
str(i) = {sprintf(’%g’,x)};
end
set(handles.edit1,’String’,’’);
set(handles.text2,’String’,str)
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15. Plotting in a GUI
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