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

Manas Vijaywargiya
Manas Vijaywargiya
12,598 Points
Posted by Manas Vijaywargiya
Manas Vijaywargiya
12,598 Points

setChecked method

Lastly, retrieve the saved value in onCreate and set the state of the CheckBox. If there isn't a saved value, the CheckBox should NOT be checked. Hint: Use the setChecked method.

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

public class MainActivity extends Activity {

  private static final String PREFS_FILE = "com.packagename.preferences";
   private static final String KEY_CHECKBOX = "KEY_CHECKBOX";

  private SharedPreferences mSharedPreferences;
  private SharedPreferences.Editor mEditor;

  public CheckBox mCheckBox;

  @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();
      mSharedPreferences.getBoolean(KEY_CHECKBOX, "");   
       mCheckBox.setChecked(true); 


  }

   @Override
    protected void onPause() {  
        super.onPause();

         mEditor.putBoolean(KEY_CHECKBOX, mCheckBox.isChecked());
         mEditor.apply();
    }
}

1 Answer

Ryan Lentz
Ryan Lentz
9,191 Points
Ryan Lentz
Ryan Lentz
9,191 Points

If there is a saved value, you want mCheckBox to have that value. If there is no saved value, you want mCheckBox to be false. Perfect place for an if/else block.

Replace:

mSharedPreferences.getBoolean(KEY_CHECKBOX, "");   
       mCheckBox.setChecked(true);

With:

 if (mSharedPreferences.getBoolean(KEY_CHECKBOX, false)) {
      mCheckBox.setChecked(true);
    } else {
      mCheckBox.setChecked(false);
    }