微调器 int 数组的空指针异常错误

Question

所以当我尝试将 dropdown3 设置为 adapter1 时，我得到一个空指针异常。但是我对字符串数组没有任何问题。为什么整数数组会发生这种情况？我能做些什么来解决它？？

public class MainActivity extends Activity {


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Spinner dropdown1 = (Spinner)findViewById(R.id.spinnertext1);
    Spinner dropdown2 = (Spinner)findViewById(R.id.spinnertext2);
    Spinner dropdown3 = (Spinner)findViewById(R.id.spinnernumber1);
    String[] items = new String[]{"ml", "oz", "L"};
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, items);
    Integer[] numbers = new Integer[]{1,2,3,4,5,6,7,8,9,10};
    ArrayAdapter<Integer> adapter1 = new ArrayAdapter<Integer>(this, android.R.layout.simple_spinner_item, numbers);
        //adapts the string "items" to be an adapter and fit into the spinner.
    dropdown1.setAdapter(adapter);
    dropdown2.setAdapter(adapter);
    dropdown3.setAdapter(adapter1);

Answer 1

我认为您不能将同一个适配器对象用于两个不同的视图。 尝试实例化三个不同的适配器。