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Argument Passing question

 
Greenhorn
Posts: 29
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Can anyone tells me why the result of the code fragment is "Blue"?
Button btn;
btn = new Button (�Pink�);
changer (btn);
System.out.println (btn.getLabel());
Public void changer (Button changeMe) {
changeMe.setLabel (�Blue�));
}
Thanks!
 
Ranch Hand
Posts: 3271
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Because a reference to the button is passed to the method. Therefore, the method is able to modify the original object through the reference.
Look here for an animated demonstration of how parameters are passed in Java.
Corey
 
Sheriff
Posts: 4313
Android IntelliJ IDE Java
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very nice animation Corey
 
Lydia Zhang
Greenhorn
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Thanks Corey, you described very clearly.
 
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