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Android Build a Simple Android App Improving Our Code Simple Refactoring: Using a New Class

Adam Sawicki
Adam Sawicki
15,967 Points
Posted by Adam Sawicki
Adam Sawicki
15,967 Points

Syntax Confusion

Hey,

Please explain me code below. I don't understand here few things:

  1. If View.OnClickListener is inteface shouldn't it be implemented rather than creating object?

  2. Why after "new View.OnClickListener()" there is curly bracket and directly after creating new object there is overriding a method. Shouldn't it be : "View.OnClickListener listener = new View.OnClickListener();" and then overriding a method?

View.OnClickListener listener = new View.OnClickListener() { @Override public void onClick(View v) { mFactTextView.setText(facts[randomNumber]); } };

Jeeya M
Jeeya M
16,839 Points

Basically it creates a new object so you don't have to write more lines than you have to and that's what android auto complete is for. In a later course you do implement it, but when your making a simple app with only a few classes, it is easier to create an object. When you create an object it creates a inner method when you can write your on click in. You don't do View.OnClickListener listener = new View.OnClickListener(); because that assigns it to a variable which you wont use again in the future. All of this is just a custom, and it doesn't really affect the functionality of the code.