Add label and text field with application code
Create button event with method

Change variable name to be better described.
Optimize output flow by disable its editable.
Remove unnecessary color changer.
Add clear data event for all text field

Optimize frame size to 400x200.
Warn user if input is empty.
Align code for better readibility.
Parse input to integer and define exception

Reformat condition logic code with convention.
Clean unnecessary listener in text field.
Use double type for number and warn if not
Better layout with panels

Group each particular component with corresponding set in
separated panel. Heading panel is available in CommonFrame,
so every section frame must have heading label.
Use BoxLayout for better component arrangement

Refer CommonFrame's content pane as the layout target container
with Y axis. Now it's a basic responsive Java design if resizeable.
Merge branch 'feature/moreAction' into develop