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Android Android Activity Lifecycle The Activity Lifecycle Saving and Retrieving Instance State

Let's practice saving and retrieving instance state. Start by initializing a key named KEY_USERENTRY.

im stuck, can you help

MainActivity.java
import android.content.Intent;
import android.view.View;

public class MainActivity extends Activity {

  public TextView mTextView;

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

    mTextView = (TextView) findViewById(R.id.textView);
  }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);

    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);



 public static final String KEY_USERENTRY="KEY_USERENTRY";


    }
}

2 Answers

alastair cooper
alastair cooper
30,617 Points

put this at the top of your MainActivity class...

private final String KEY_USERENTRY  = "KEY_USER_ENTRY";

To initialise means to give a start value to something. The key is the name you will use to access the data you are saving. This will never change, so you can declare the key 'final'

Thank you it worked

Adding to Alastair Cooper's answer, on top of being final, as a constant, the key should also be defined as static.

fg

Tafadzwa Nyazorwe
Tafadzwa Nyazorwe
1,322 Points

private static final String KEY_USERENTRY = "KEY_USER_ENTRY";