Chapter 4: Programming in Matlab - College of the Redwoods

416 Chapter 4 Programming in Matlab
hLineWidthText=uicontrol(...
’Style’,’text’,...
’Parent’,hPanel,...
’Position’, [10 180 180 20],...
’String’, ’Enter Desired LineWidth: (1-10)’,...
’HorizontalAlignment’,’Left’,...
’BackgroundColor’, panel_color);
Next, to initialize the edit box for our GUI, enter the following lines just below
the last uicontrol, the static text control with handle hLineWidthText.
hLineWidthEditbox=uicontrol(...
’Style’,’edit’,...
’Parent’,hPanel,...
’Units’,’Pixels’,...
’Position’, [10 150 180 25],...
’String’,’1’,...
’BackgroundColor’, buttongroup_color,...
’Callback’, @LineWidthEditbox_callback);
Some comments are in order.
• Note that the ‘Style’ is ‘edit’, so this uicontrol is a dynamic edit box, one
where both user and program can modify the text inside.
• The parent is the uipanel, so the position of the edit box will be measured
from the lower left-hand corner of the panel with handle hPanel.
• We intialize ‘String’ to ‘1’. This will be the intial value that appears in the
edit box. It represents a line width of 1 point (1 pt).
• We assign the function handle @LineWidthEditbox_callback to the ‘Callback’
property.
At this point, if you attempt to modify the text in the dit box, you will
receive an error as the callback function LineWidthEditbox_callback is not
yet written. Let’s take care of that immediately and write the callback.
As usual, the obligatory arguments hObject and eventdata are used.