Showing Alert of empty axes box.
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When the Axes Box does not contain any image and user clicks on the Push button then an error should popup saying "Please upload an image" or something else, how to do that how check whether the axes box is empty or not?
댓글 수: 2
Jan
2017년 6월 1일
Please provide any details. Show us the relevant part of the code, e.g. the button's callback. Do you have the handle of the axes? Does the axes contain any other child objects? What about setting a flag, when the image is imported?
채택된 답변
Walter Roberson
2017년 6월 1일
Set the 'enable' property of the Extract button to 'off' at the start of the program. When the user has uploaded or captured an image, set the enable property to 'on'. That way it is not possible for the Extract button to be clicked when there is no image to extract from.
댓글 수: 8
Walter Roberson
2017년 6월 3일
function Load_Callback(hObject, eventdata, handles)
[filename, pathname]=uigetfile({'*.jpg';'*.jpeg';'*.gif';'*.png';'*.bmp'},'Select file');
global MyImage;
MyImage = fullfile(pathname, filename);
im = imread(MyImage);
imshow(im, 'Parent', handles.axes1);
handles.have_loaded_something = 1;
guidata(hObject, handles);
function Extract_Callback(hObject, eventdata, handles)
global MyImage;
global noPlate;
if ~isfield(handles, 'have_loaded_something')
handles.have_loaded_something = 0;
guidata(hObject, handles);
end
if ~handles.have_loaded_something
msgbox('You need to load an image!', 'modal');
return
end
numberPlateExtraction(MyImage);
set(handles.edit1, 'string', noPlate);
추가 답변 (2개)
Adam
2017년 6월 1일
편집: Adam
2017년 6월 1일
Declare e.g.
handles.hImage = [];
at the start of your program, then just set this when you plot the image as e.g.
handles.hImage = imagesc( hAxes,... );
Then in your pushbutton callback you can just test
if isempty( handles.hImage )
errordlg( 'Please upload an image' )
return
end
댓글 수: 16
Image Analyst
2017년 6월 3일
Why not simply use getimage() like I suggested to find out if there is any image in the axes???
Image Analyst
2017년 6월 1일
You can use getimage() to see if there is any image in the axes. It will be empty if you have not loaded an image yet (with a function such as imshow, image, imagesc, etc.). Use axes() to switch the current axes to the one you care about, then:
theImage = getimage();
if isempty(theImage)
% Nothing is in the current axes.
uiwait(warndlg('Please load an image'));
end
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