How to create an empty edit field (numeric) in app designer
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I am writing an app that has a user enter a quantity in a numeric Edit Field. The field starts off with a default value of 0 so that the user has to delete the 0 and then enter the number. Is there a way to get the default to be empty rather than a 0?
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Marc Youcef
2019-8-13
I was searching for same request but apprently there is no way to do that using uinumericeditfield as this edit field forces you to have at list a numeric value. Which is a pain when you do not want the user to necessarly enter something in, you get a 0 value instead of empty field...
回答(4 个)
Gonzalo Montero
2019-12-12
I'm looking for the same feature, it's a pity that is not possible!
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Chris
2019-8-13
Can you make the input a text field and reject anything that does not convert to a number?
2 个评论
Marc Youcef
2019-8-13
Yes, this is the only solution I thought about. Unfortunately in my case I was trying to take advantage of the 'uinumericeditfield' functionnality which is doing exactly this for you and wanted to simply add an 'empty by default' option.
frankenberry
2020-5-21
I was able to use a blank text area to accept only numbers. I'm not sure how good it is or if it helps you at all. The only problem I have with this is that if the field is blank, it should also give an error. That is, I get an error if the value is not a number and the error box pops up or if it is blank, I should get an error. I need to code that part yet. I tested this and it works in my app. I don't get an error when numbers are entered.
% Value changed function: NEQO_A4_pistol
function NEQO_A4_pistolValueChanged(app, event)
value = app.NEQO_A4_pistol.Value;
string(value);
if isempty(str2num(value))
app.NEQO_A4_pistol.Value,value;'0';
uialert(app.UIFigure, {'You need to enter a number','Click OK and enter a number value'}, 'Error', 'Icon', 'Error');
app.NEQO_A4_pistol.Value = '';
elseif ~isempty(str2num(value))
app.NEQO_A4_pistol.Value,value;'0', '1', '2', '3', '4', '5', '6', '7', '8', '9';
%uialert(app.UIFigure, {'You entered a number! WOOHOO!'}, 'Info', 'Icon', 'info');
end
end
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