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Gonzalo Nunez
Courses Plus Student 5,064 PointsTypes of casting
Hi,
I´m a little confuse about when I use, parse or, toString(), or this example: mStartButton = (Button) findViewbyId(R.id.startButton);
What the difference between then?
When do I use:Ex -parseString -toString()
- or (String) findViewxxxxxxxx
This is all diferent types of casting?
1 Answer
Ben Deitch
Treehouse TeacherObject.toString() is a method that returns a string that "textually represents" the object in question. And since this method is on the Object class, every class that extends the Object class (aka every class, since all classes either directly or indirectly extend the Object class), will have a 'toString()' method.
Integer.parseInt(String arg) (or Float.parseFloat, or Double.parseDouble...) takes in a String (formatted as a number) and converts it to an int.
(Button) is a cast. findViewById(...) returns an object of type View, but we can't put an object of type View into our mStartButton variable; it's expecting an object of type Button. So since we know that R.id.startButton represents a Button, we can just add the cast, (Button), to cast it to a Button object.