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Android Android Activity Lifecycle Introducing SharedPreferences Saving and Retrieving Data with SharedPreferences

Unable to get this question

Do I have to use if-else to identify the true and false cases ?

MainActivity.java
import android.view.View;
import android.os.Bundle;

public class MainActivity extends Activity {

  public CheckBox mCheckBox;
  private static final String PREFS_FILE = "PREFS_FILE.preferences";
  private static final String KEY_CHECKBOX = "KEY_CHECKBOX";
  private SharedPreferences mSharedPreferences;
  private SharedPreferences.Editor mEditor;

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

    mCheckBox = (CheckBox) findViewById(R.id.checkBox);
    mSharedPreferences = getSharedPreferences(PREFS_FILE,Context.MODE_PRIVATE);
    mEditor = mSharedPreferences.edit();

       Boolean checkBoxBoolean = mSharedPreferences.getBoolean(KEY_CHECKBOX,"");

    mCheckBox.setChecked(checkBoxBoolean);
  }

   @Override
  protected void onPause() 
  {
    super.onPause();
    mEditor.putBoolean(KEY_CHECKBOX,mCheckBox.isChecked());
    mEditor.apply();
  }

}

1 Answer

Seth Kroger
Seth Kroger
56,407 Points

The main problem is you have the default value for getBoolean as an empty string but a boolean can only be true or false, so the default is the wrong type.

Also you should put the code for getting the saved preferences in onResume(), not onCreate().

Thanks having "false" instead of empty braces helped. Actually I did try the same before and was getting recompile error in the preview Tab. Thanks for guidance though.