Using intent and bundle for integers in Android

问题:

Say I wanted to pass data from one activity/class to the other involving an integer data type. Here's what I have for the MainActivity (first) class so far:

@Override
public void onClick(View v) {
    Intent i = new Intent(this, SecondActivity.class);
    final int x = 3;
    i.putExtra("new variable", x);
    startActivity(i);
}

For the receiving class, SecondActivity:

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_second);

    Bundle i = getIntent().getExtras();
    String value = i.getString("new variable");
    tvResult = (TextView)findViewById(R.id.textViewResult);
    tvResult.setText(value);
}

However, SecondActivity shows up with nothing on the second screen... Could it perhaps be because I need to convert value to an int first?

Thanks!

回答1:

I wanted to pass data from one activity/class to the other involving an integer data type...

x is int but in SecondActivity i.getString is used to get data from Bundle which return String instead of int.

Use Bundle.getInt to get int from Bundle.

int value = i.getInt("new variable");

Also use String.valueOf for showing int in TextView as:

tvResult.setText(String.valueOf(value));