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Using .getText() and .append()

 
Greenhorn
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The purpose of this program is simple - input a string from a JTextField and append it to the end of a JTextArea. I'm getting null pointer exceptions when I try to use .getText, though. Is this a problem of scope?

 
Bartender
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Originally posted by Joe Lank:
Is this a problem of scope?



Somewhat. You are declaring two variables called output and assigning a value to only one.
 
Ranch Hand
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In addition to shadowing the fields with local variables of the same name, you probably don't want to be using static field here. If created multiple instances of the tester class, all of the action events would append the text in the most recently constructed window to the the text area in the most recently constructed window (as opposed to the active window in where the event happened).
 
Joe Lank
Greenhorn
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Fixed, danke alle.
 
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