Array initializer is not allowed here [duplicate]

问题:

This question already has answers here:

How to initialize an array in Java? (10 answers)

Closed 6 months ago.

I am working on Android project and I am getting an error which I cannot understand:

Array initializer is not allowed here

I tried to simplify my code and it comes down to this

public class MainActivity extends Activity{

    int pos = {0, 1, 2};

    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        pos = {2, 1, 0};
    }
}

What is going on here?

回答1:

You should use

pos = new int[]{1,2,3};

You can only use the abbreviated syntax int[] pos = {0,1,2}; at variable initialization time.

private int[] values1 = new int[]{1,2,3,4};
private int[] values2 = {1,2,3,4}; // short form is allowed only at variable initialization

回答2:

Your initialization statement is wrong: you must add square brackets to declare an array (and here you can omit the new keyword because you're declaring and initializing the variable at the same time):

int[] pos = { 0, 1, 2 };

In the onCreate method, you can't omit the new keyword because the variable was already declared, so you have to write:

pos = new int[] { 2, 1, 0 };

You can read the Oracle documentation and the Java Language Specs for more details.

回答3:

use the following syntax to declare/initialize and empty array, and then populated it with data:

String[] menuArray = {};
menuArray = new String[]{"new item","item 2"};

回答4:

This is a compile-time error Illegal Initializer for int. You could solve this problem by adding square braces after your variable's data type like this:

int[] pos = {0, 1, 2};