[:en]Android: SharedPreferences[:]

[:en]SharedPreferences

Step 1: activity_main.xml

Step 2: MainActivity.java

package com.example.cambridge.sharedpreferences;

import android.content.Context;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    EditText usernameInput;
    EditText passwordInput;
    TextView displaylabel;



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

        usernameInput = (EditText)findViewById(R.id.userid);
        passwordInput = (EditText)findViewById(R.id.passwordid);
        displaylabel    = (TextView)findViewById(R.id.displayid);

    }

    // Save the users login info
    public void saveData(View view){

        // Create a private file
        SharedPreferences sharedPref = getSharedPreferences("userInfo", Context.MODE_PRIVATE);

        // Create an object
        SharedPreferences.Editor editor = sharedPref.edit();
        //Store data with a key
        editor.putString("username", usernameInput.getText().toString());
        editor.putString("password", passwordInput.getText().toString());
        editor.apply();

        Toast.makeText(this,"Saved!",Toast.LENGTH_LONG).show();
    }

    // Print out the saved data
    public void displayData(View view){
        SharedPreferences sharedPref = getSharedPreferences("userInfo", Context.MODE_PRIVATE);
        String name = sharedPref.getString("username", "");
        String pw = sharedPref.getString("password", "");
        displaylabel.setText(name + " " + pw);
    }
}

Or simple way to remember:

       //Store data with a key
       SharedPreferences sharedPref = getSharedPreferences("userInfo", Context.MODE_PRIVATE);
       loginstatus = "in";
       SharedPreferences.Editor editor2 = sharedPref.edit();
       editor2.putString("loginkey", loginstatus);
       editor2.apply();  


       // Recall stored data
       SharedPreferences sharedPref = getSharedPreferences("userInfo", Context.MODE_PRIVATE);
       loginstatus = sharedPref.getString("loginkey", "");
        if (loginstatus.equals("in")){
            startActivity(new Intent(MainActivity.this, menu.class));
        } else {
           // do nothing
        } 

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