App Designer returning Value in EditField

Question

Giancarlo Meccariello 2021-3-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/766166-app-designer-returning-value-in-editfield

评论： Giancarlo Meccariello 2021-3-8

I wrote a code to calculate some values I insert in the Edit fields.

First of all do I have a DropDown Menu, with some values which I want to calculate with.

After I performe the calculation (with the value from DropDownMenu and values from EditField) do I want to return the result in an Edit field.

If run the programm and Insert all my values do I get the following error:

"Error using matlab.ui.control.internal.model.AbstractNumericComponent/set.Value (line 111)

'Value' must be a double scalar."

That's my code for the DropDown menu. I want to safe the value in the variable "app.d_th"

        % Value changed function: aDropDown
        function aDropDownValueChanged(app, event)
            app.d_th = app.aDropDown.Value
        end

I have a Calculation Button which looks like this. I have shortened the entire calculation. that's just to show you how it looks. The goal is when I press the Button I want to performe the calculation and display it in the "ResultEditField"

                % Value changed function: BerechnenButton
        function BerechnenButtonValueChanged(app, event)
        value = app.BerechnenButton.Value;
       
d_th = app.d_th/1000 %in meter. 3.6mm = 0.0036m
p_h = app.p_h * 10^5 %Hochdruck in pascal
m_flow =  d_th.^2 + p_h 
app.ResultEditField.Value = m_flow
        end

Any hints?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Mario Malic 2021-3-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/766166-app-designer-returning-value-in-editfield#answer_641946

编辑：Mario Malic 2021-3-8

Hi,

app.aDropDown.Value is one of the values in Items (if ItemsData is empty), therefore it's a character array.

if you set ItemsData as well to be numeric, then Value property will be of the same type. However, you can keep it simple and use line below to fix the issue.

app.d_th = str2num(app.aDropDown.Value)

5 个评论
显示 3更早的评论隐藏 3更早的评论

Mario Malic 2021-3-8

Hm, you'll have to convert the output of these as variable types are different, even though their values are the same. On this one, you'll have to use the search tool and find related questions.

Giancarlo Meccariello 2021-3-8