12.8 How Event Handling Works
Let’s illustrate how the event-handling mechanism works, using textField1
from the example of Fig. 12.9. We have two remaining open questions from Section 12.7:
1. How did the event handler get registered?
2. How does the GUI component know to call actionPerformed
rather than some other event-handling method?
The first question is answered by the event registration performed in lines 43–46 of Fig. 12.9. Figure 12.13 diagrams JTextField
variable textField1
, TextFieldHandler
variable handler
and the objects to which they refer.
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