Manage Resizable Apps in App Designer
Apps you create in App Designer are resizable by default. The components reposition
            and resize automatically as the user changes the size of the window at run-time. The
                AutoResizeChildren property controls this automatic resize
            behavior. By default, App Designer enables this property for the UI figure and all its
            child containers such as panels and tabs. To set the
                AutoResizeChildren property of a child container to a different
            value, set the value for the child container after setting the value for the parent.

When the AutoResizeChildren property is enabled for a container,
                MATLAB® manages the size and position of only the immediate children in the
            container. Components in nested containers are managed by the
                AutoResizeChildren property of their immediate parent. To
            ensure that the alignment of components relative to one another (like a grouping of
            buttons) is preserved when your app is resized, parent the grouping of components to a
            panel, instead of directly to the figure.
Resizing Graphics Objects with Normalized Position Units
When graphics objects, like axes or charts, use normalized position units and are
                the child of a resizable container, certain properties of the graphics object are
                affected after the parent container is resized. For example, if axes or charts use a
                value of 'normalized' for the Units property
                and are parented to a container with the AutoResizeChildren
                property set to 'on', then:
The value of the
OuterPositionproperty for the axes or chart changes when the app is resized.The axes or chart does not shrink smaller than a minimum size when the app is resized.
If you want to avoid either of these behaviors, set the
                    AutoResizeChildren property of the container to
                    'off'.
Alternatives to Default Auto-Resize Behaviors
If you want more flexibility over how your app automatically resizes, use grid
                layout managers or the auto-reflow options in App Designer instead of the
                    AutoResizeChildren property. For more information about
                these options, see:
If the resize behaviors supported by AutoResizeChildren, grid
                layout managers, or auto-reflow options are not the behaviors you want, then you can
                create custom resize behaviors by writing a SizeChangedFcn
                callback function for the container. For more information, see Manage App Resize Behavior Programmatically.