MATLAB: Error using subplot with App Designer

appdesignerMATLABplotsubplotuiaxes

Hi everyone,
I'm continuously facing the error "Error using handle. Cannot convert to handle." when trying to plot different data into subplot in App Designer.
At the moment I coded the following code (those data works regularly if I plot them not in App Designer).
"bdays" and all other "dataN" variables are 398×1 double as format.
load('MyData.mat','-mat');
app.UI_Axes.AutoResizeChildren = 'off';
ax1 = subplot(10,1,[1 7],'Parent',app.UI_Axes);
plot(ax1,bdays,data1,'b');
hold(ax1,'on');
plot(ax1,bdays,data2,'r');
plot(ax1,bdays,data3,'c');
if (ShowOne)
    plot(ax1,data4,'k');
end
ax2 = subplot(10,1,[8 10],'Parent',app.UI_Axes);
plot(ax2,bdays,data5,'b');
hold(app.UI_Axes,'on');
plot(ax2,bdays,data6,'r');
if (ShowOne)
    plot(ax2,bdays,data7,'k');
end

Best Answer

The parent of a subplot (ie, axes) should be a figure (or Panel objects, Tab object, or TiledChartLayout object). You're using another axis handles as the parent. 
f = uifigure(); 
f.AutoResizeChildren = 'off'; 
subplot(2,2,1,'Parent',f)
Note: in appdesigner, the f variable will be the handle to the app figure.
I'm wondering why you need to add subplots to the app from within the code. Wouldn't it be more efficient to produce all of the axes from within the AppDesigner user interface and then control their visiblity?
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