以编程方式在textview中显示IMEI

Question

我想要一个代码来获取IMEI并在textview中显示

这是我的代码：

public class Main extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    String IMEI;
    IMEI = retrieve_IMEI.get_dev_id().toString();
    TextView tv = (TextView) findViewById(R.id.textView1);
    tv.setText(IMEI);

}



public static class retrieve_IMEI {

    public static String get_dev_id() {

        Context ctx = null;
        // Getting the Object of TelephonyManager
        TelephonyManager tManager = (TelephonyManager) ctx.getSystemService(Context.TELEPHONY_SERVICE);

        // Getting IMEI Number of Device
        String Imei = tManager.getDeviceId();

        return Imei;
      }
  }

我使用READ_PHONE_STATE权限

当我运行我的代码时，我会关闭力量。我该怎么办？

Answer 1

您的上下文ctx为null，您正在使用它访问TelephonyManager类。请正确初始化

Answer 2

public class Main extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    String IMEI;
    IMEI = retrieve_IMEI.get_dev_id(this).toString();
    TextView tv = (TextView) findViewById(R.id.textView1);
    tv.setText(IMEI);

}



public static class retrieve_IMEI {

    public static String get_dev_id(Context ctx) {

        // Getting the Object of TelephonyManager
        TelephonyManager tManager = (TelephonyManager) ctx.getSystemService(Context.TELEPHONY_SERVICE);

        // Getting IMEI Number of Device
        String Imei = tManager.getDeviceId();

        return Imei;
      }
  }