Introduction

This application is to create and maintain Session Values in Xamarin Android.

Step 1 : Open Visual Studio->New Project->Templates->Visual C#->Android->Blank App->Select Blank App (Android). Then give Project Name and Project Location.

Step 2 : Next go to Solution Explorer-> Project Name then Right Click to Add->Class and open new Dialog box.

Step 3 : Dialog box to select Class and give the Name AppPreferences.cs,

Step 4 : Next, Open Solution Explorer->Project Name->Resources->AppPreferences.cs. Click to open the following code.

C# Code :-

 using System; 
 using System.Collections.Generic; 
 using System.Linq; 
 using System.Text; 
 using Android.App; 
 using Android.Content; 
 using Android.OS; 
 using Android.Runtime; 
 using Android.Views; 
 using Android.Widget; 
 using Android.Preferences; //Add New NameSpace 
 namespace SharedPreference 
 { 
 public class AppPreferences 
 { 
 private ISharedPreferences nameSharedPrefs; 
 private ISharedPreferencesEditor namePrefsEditor; //Declare Context,Prefrences name and Editor name 
 private Context mContext; 
 private static String PREFERENCE_ACCESS_KEY = "PREFERENCE_ACCESS_KEY"; //Value Access Key Name 
 public static String NAME = "NAME"; //Value Variable Name 
 public AppPreferences(Context context) 
 { 
 this.mContext = context; 
 nameSharedPrefs = PreferenceManager.GetDefaultSharedPreferences(mContext); 
 namePrefsEditor = nameSharedPrefs.Edit(); 
 } 
 public void saveAccessKey(string key) // Save data Values 
 { 
 namePrefsEditor.PutString(PREFERENCE_ACCESS_KEY, key); 
 namePrefsEditor.Commit(); 
 } 
 public string getAccessKey() // Return Get the Value 
 { 
 return nameSharedPrefs.GetString(PREFERENCE_ACCESS_KEY, ""); 
 } 
 } 
 }

Step 5 : Then Open Solution Explorer->Project Name->Resources->layout->Main.axml, then click open Design View. Select Toolbar, then Drag and Drop design of Buttons, TextView, PlainText.

XML Code :-

  <?xml version="1.0" encoding="utf-8"?> 
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:orientation="vertical" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent"> 
 <TextView 
 android:text="Enter Name" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/Text" /> 
 <EditText 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/txtsave" /> 
 <Button 
 android:text="Save" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/btnsave" /> 
 <TextView 
 android:text="GET SAVED NAME" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/textView2" /> 
 <TextView 
 android:text="" 
 android:textAppearance="?android:attr/textAppearanceLarge" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/txtgetname" /> 
 <Button 
 android:text=" GET STORED DATA" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/btnget" /> 
 <Button 
 android:text="Delete Preferences" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content" 
 android:id="@+id/btnreset" />

Step 6 : Then open Solution Explorer->Project Name->MainActivity.cs. Click to open C# Code page. Then go to section OnCreate() and declare create Button, TextView and EditText Events.

C# Code :-

 using System; 
 using Android.App; 
 using Android.Content; 
 using Android.Runtime; 
 using Android.Views; 
 using Android.Widget; 
 using Android.OS; 
 using Android.Preferences; 
 namespace SharedPreference 
 { 
 [Activity(Label = "SharedPreference", MainLauncher = true, Icon = "@drawable/icon")] 
 public class MainActivity : Activity 
 { 
 Button btnsave; 
 Button btnget; 
 Button btnreset; 
 EditText txtname; 
 TextView txtview; 
 protected override void OnCreate(Bundle bundle) 
 { 
 base.OnCreate(bundle); 
 SetContentView(Resource.Layout.Main); 
 btnsave = FindViewById<Button>(Resource.Id.btnsave); 
 btnget = FindViewById<Button>(Resource.Id.btnget); 
 btnreset = FindViewById<Button>(Resource.Id.btnreset); 
 txtname = FindViewById<EditText>(Resource.Id.txtsave); 
 txtview = FindViewById<TextView>(Resource.Id.txtgetname);
 
 btnsave.Click += Btnsave_Click; 
 btnget.Click += Btnget_Click; 
 btnreset.Click += Btnreset_Click; 
 } 
 }

Step 7 : Next to create Save Button Event, save the entered text in textbox values. It is the value to maintain Session of AppPreferences.

C# Code :-

 private void Btnsave_Click(object sender, EventArgs e) 
 { 
 //Save Sessionvalue 
 Context mContext = Android.App.Application.Context; 
 AppPreferences ap = new AppPreferences(mContext); 
 ap.saveAccessKey(txtname.Text); 
 txtname.Text = ""; 
 }

Step 8 : Next to create Get Button Event, this event work to retrieve the AppPreferences stored value. After Retrieve Value it will display in TextView.

C# Code :-

 private void Btnget_Click(object sender, EventArgs e) 
 { 
 //Get Sessionvalue 
 Context mContext = Android.App.Application.Context; 
 AppPreferences ap = new AppPreferences(mContext); 
 string key = ap.getAccessKey(); 
 txtview.Text = key.ToString(); 
 } 

 private void Btnreset_Click(object sender, EventArgs e) 
 { 
   ISharedPreferences pref = PreferenceManager.GetDefaultSharedPreferences(this); 
   ISharedPreferencesEditor editer = pref.Edit(); 
   editer.Remove("PREFERENCE_ACCESS_KEY").Commit(); ////Remove Spec key values 
 }

Anbu Mani

Anbu Mani(Microsoft MVP) is working Software Engineer in Changepond Technologies, Chennai, Tamilnadu, India. Having 4+ years of experience and his area of interest is C#, ASP.NET, SQL Server, Xamarin and Xamarin Forms,Azure…etc

anbumani.dev/