21 lines
1005 B
Plaintext
21 lines
1005 B
Plaintext
Almost every application needs to communicate with the user in some way.
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Therefore, a substantial part of the code deals with the interaction of program
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logic with GUI components. Typically, the following is needed:
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* put values into input fields under program control
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* read and check input from the user
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* pop up dialogs to query the user for further information
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The task: For a minimal "application", write a program that presents a form with
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three components to the user: A numeric input field ("Value") and two buttons
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("increment" and "random").
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The field is initialized to zero. The user may manually enter a new value into
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the field, or increment its value with the "increment" button. Entering a
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non-numeric value should be either impossible, or issue an error message.
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Pressing the "random" button presents a confirmation dialog, and resets the
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field's value to a random value if the answer is "Yes".
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(This task may be regarded as an extension of the task [[Simple windowed application]]).
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