Almost every application needs to communicate with the user in some way.
Therefore, a substantial part of the code deals with the interaction 
of program logic with GUI components. 

Typically, the following is needed:

* put values into input fields under program control
* read and check input from the user
* pop up dialogs to query the user for further information


;Task:
For a minimal "application", write a program that presents a form with three components to the user:
::* a numeric input field ("Value") 
::* a button ("increment")
::* a button ("random")


The field is initialized to zero. 

The user may manually enter a new value into the field, 
or increment its value with the "increment" button. 

Entering a non-numeric value should be either impossible, 
or issue an error message.

Pressing the "random" button presents a confirmation dialog, 
and resets the field's value to a random value if the answer is "Yes".

(This task may be regarded as an extension of the task [[Simple windowed application]]).<br><br>

