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

Yuri Arons
Yuri Arons
7,281 Points
Posted by Yuri Arons
Yuri Arons
7,281 Points

can't get it right !

Help !

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

public class MainActivity extends Activity {

  private static final String PREFS_FILE = "com.teamtreehouse.sharedpreferencesapp.preferences";
  private static final String KEY_CHECKBOX = "key_checkbox";
  private SharedPreferences.Editor mEditor;
  private SharedPreferences mSharedPreferences;
  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.getString(KEY_CHECKBOX, "");
  }

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

  }
}

2 Answers

Dean Silvestro
PLUS
Dean Silvestro
Courses Plus Student 20,733 Points
Dean Silvestro
Dean Silvestro
Courses Plus Student 20,733 Points

That part of the challenge can be a little tricky but if you watch the video again I think you'll pick up on what onPause requires to function properly.

The answer you're looking for if you're still stuck is: 

  @Override
  protected void onPause() {
  super.onPause();
    mEditor.putBoolean(KEY_CHECKBOX, mCheckBox.isChecked());
    mEditor.apply();
  }
Yuri Arons
Yuri Arons
7,281 Points
Yuri Arons
Yuri Arons
7,281 Points

i did what you suggested ... and it's not working ... :(

Dean Silvestro
Dean Silvestro
Courses Plus Student 20,733 Points
Dean Silvestro
Dean Silvestro
Courses Plus Student 20,733 Points

The string of question marks in your original question was located in the onPause method. I thought that part of the challenge was the only part you needed help with. The complete answer is:

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

public class MainActivity extends Activity {

  private static final String PREFS_FILE = "com.teamtreehouse.sharedpreferencesapp.preferences";
  private static final String KEY_CHECKBOX = "key_checkbox";
  private SharedPreferences.Editor mEditor;
  private SharedPreferences mSharedPreferences;
  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();

    boolean checkBoxBoolean = mSharedPreferences.getBoolean(KEY_CHECKBOX, false);
    mCheckBox.setChecked(checkBoxBoolean);
  }

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

You could do some research in the documentation about the "getBoolean" method needed to see why it needs the default value of false as the second parameter. Otherwise, everything else was explained in the preceding video. Hope this helps! :)

Yuri Arons
Yuri Arons
7,281 Points
Yuri Arons
Yuri Arons
7,281 Points

you r the best ! thnx !!