how to read the "?" operator

Question

I don't know how to read this code. what is the equivalent code with if/else statements?

            leftPanel.getLayoutParams().width = interpolatedTime == 1
                    ? ViewGroup.LayoutParams.WRAP_CONTENT
                    : (int)(targetWidth * interpolatedTime);

Simply: `boolean expression ? value if true : value if false` — Bubletan, Jan 26 '15 at 19:00
This is a ternary operator syntax in java and it says... 1. Check if `interpolatedTime == 1`, then assign `leftPanel.getLayoutParams().width = ViewGroup.LayoutParams.WRAP_CONTENT`. 2. Else assign `leftPanel.getLayoutParams().width = (int)(targetWidth * interpolatedTime)`. — Aninda Bhattacharyya, Jan 26 '15 at 19:44

score 3 · Accepted Answer · edited Jan 26 '15 at 19:00

3

It is called the ternary operator and is exactly equivalent to:

if(interpolatedTime == 1) {
    leftPanel.getLayoutParams().width = ViewGroup.LayoutParams.WRAP_CONTENT;
} else {
   leftPanel.getLayoutParams().width = (int)(targetWidth * interpolatedTime);
}

See http://docs.oracle.com/javase/tutorial/java/nutsandbolts/op2.html for the Oracle documentation for it.

edited Jan 26 '15 at 19:00

aryn.galadar

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answered Jan 26 '15 at 18:58

M A

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how to read the "?" operator

1 Answers1