Pass data from one activity to another using Intent in Xamarin

In this Article, we will see how to pass data from one activity to another using Intent in Xamarin. In my previous Article, we learnt about Checkbox widget in Xamarin.

Let's Begin:
1. Create a new Android Application.

2. Add a layout (named as Main.axml).

3) Drop TextView, EditText(set id="@+id/txt_Name") and Button(set id="@+id/btn_Submit" and text="Submit") control onto the Main.axml Layout.

4) Add another Layout and name it as Result.axml.

Drop TextView(Large) control on Result.axml layout and set id="@+id/txt_Result".

Activity1.cs Code:

using System; using Android.App; using Android.Content; using Android.Widget; using Android.OS; namespace IntentDemo {     [Activity(Label = "IntentDemo", MainLauncher = true, Icon = "@drawable/icon")]     public class Activity1 : Activity     {         EditText txt_Name;         Button btn_Submit;         protected override void OnCreate(Bundle bundle)         {             base.OnCreate(bundle);             // Set our view from the "main" layout resource             SetContentView(Resource.Layout.Main);             //Get txt_Name and btn_Submit Button CheckBox control from the Main.xaml Layout.              txt_Name = FindViewById<EditText>(Resource.Id.txt_Name);             btn_Submit = FindViewById<Button>(Resource.Id.btn_Submit);             //btn_Submit click event             btn_Submit.Click += btn_Submit_Click;         }         void btn_Submit_Click(object sender, EventArgs e)         {             //if EditText in not Empty             if(txt_Name.Text!="")             {                 //passing the Activity2 in Intent                 Intent i = new Intent(this,typeof(Activity2));                 //Add PutExtra method data to intent.                 i.PutExtra("Name",txt_Name.Text.ToString());                 //StartActivity                 StartActivity(i);             }             else             {                 Toast.MakeText(this,"Please Provide Name",ToastLength.Short).Show();             }         }     } }

In above Code, We have created an Intent and Bind Activity2 to it. PutExtra method of Intent allows us to store data in Key-Value pairs. We can retrieve the data in the other Activity using Intent. GetTypeExtra method. In above Code, We have passed string using PutExtra() method and for Retrieving the string in another activity, we use Intent.GetStringExtra("Name") method and pass key value in it as a parameter.
Activity2.cs Code:

using Android.App; using Android.Content; using Android.OS; using Android.Widget; namespace IntentDemo {     [Activity(Label = "Result")]     public class Activity2 : Activity     {         protected override void OnCreate(Bundle bundle)         {             base.OnCreate(bundle);             // Set our view from the "Result" layout resource             SetContentView(Resource.Layout.Result);             //Get txt_Result TextView control from the Main.xaml Layout.              TextView txt_Result = FindViewById<TextView>(Resource.Id.txt_Result);             //Retrieve the data using Intent.GetStringExtra method             string name = Intent.GetStringExtra("Name");             txt_Result.Text ="Hello, "+name;         }     } }

Final Preview:

Hope you like it. Thanks.

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CheckBox Widget in Xamarin

In this Article, We will see How to use CheckBox widget control and CheckBox's CheckedChange Event in Xamarin.For Demonstration, I am going to create a Simple application in which if user accept the terms and condition(using CheckBox) then Submit button become enabled. Before starting, I suggest you read my previous articles of this series.

• Hello World Application in Xamarin
• Creating Splash Screen for Android App in Xamarin. 
• Auto Complete Text View in Xamarin

Let's Begin:
1) Create a New Android Application.

2) Drop a CheckBox (with id="@+id/checkBox1") and Button (with id="@+id/btn_Submit") control onto the Layout, Main.axml.

Set the Text of CheckBox as Accept Terms and Condition and Button's Text as Submit.

Main.axml 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">     <CheckBox         android:text="Accept Terms and Conditions"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:id="@+id/checkBox1" />     <Button         android:text="Submit"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:id="@+id/btn_Submit"         android:enabled="false" /> </LinearLayout>

In Activity1.cs, We have created CheckBox CheckedChange Event. The following is Activity1.cs Code:

using System; using Android.App; using Android.Content; using Android.Runtime; using Android.Views; using Android.Widget; using Android.OS; namespace CheckBoxDemo {     [Activity(Label = "CheckBoxDemo", MainLauncher = true, Icon = "@drawable/icon")]     public class Activity1 : Activity     {         //Create instance of Button         Button btn_Submit;         protected override void OnCreate(Bundle bundle)         {             base.OnCreate(bundle);             //setting the view for the Activity              SetContentView(Resource.Layout.Main);             //Get btn_Submit Button and checkBox1 CheckBox control from the Main.xaml Layout.             btn_Submit = FindViewById<Button>(Resource.Id.btn_Submit);             CheckBox checkBox1 = FindViewById<CheckBox>(Resource.Id.checkBox1);             //CheckBox CheckedChange Event             checkBox1.CheckedChange += checkBox1_CheckedChange;             //btn_Submit Click Event             btn_Submit.Click += btn_Submit_Click;         }         void checkBox1_CheckedChange(object sender, CompoundButton.CheckedChangeEventArgs e)         {             //If CheckBox is Checked             if(e.IsChecked==true)             {                 btn_Submit.Enabled = true;             }             else             {                 btn_Submit.Enabled = false;             }         }         void btn_Submit_Click(object sender, EventArgs e)         {             Toast.MakeText(this,"Thanks for accepting Terms and Condition",ToastLength.Short).Show();         }     } }

Final Preview:

Hope you like it. Thanks.

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AutoCompleteTextView in Xamarin

AutoCompleteTextView is an Editable TextView used for displaying suggestion when user starts typing in the control. Suggestion is displayed in a drop down menu and when user select the item from the drop down list, the selected text is displayed in a TextView. Before starting, I suggest you to read my previous Article.

• Hello World Application in Xamarin
• Creating Splash Screen for Android App in Xamarin.

Let's Start:

Method 1:(using Default Android Resources)
1) Create New Android Application.

2) Drop TextView, AutoCompleteTextView(with id="@+id/autoComplete1") and a Button control(with id="@+id/btn_Submit" and text="Submit") on Layout i.e. Main.axml

Main.axml Source 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:textAppearance="?android:attr/textAppearanceMedium"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:id="@+id/textView1"         android:padding="5dp" />     <AutoCompleteTextView         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:id="@+id/autoComplete1" />     <Button         android:text="Submit"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:id="@+id/btn_Submit" /> </LinearLayout>

In Activity1.cs, Create a String Array (named as names) used for Displaying AutoComplete Suggestion and an ArrayAdapter for filling the View i.e. AutoCompleteTextView with the list of names(Array). We have also created a btn_Submit.Click event. On Clicking the btn_Submit it will display the text present in autoComplete1 AutoCompleteTextView in a Toast message and if AutoCompleteTextView is empty than Display a Toast Message(in other words Please Enter Name!).
Activity1.cs Code:

using Android.App; using Android.Widget; using Android.OS; namespace AutoCompleteTextViewExample {     [Activity(Label = "AutoCompleteTextViewExample", MainLauncher = true, Icon = "@drawable/icon")]     public class Activity1 : Activity     {         //Creating Instance of AutoCompleteTextView and Button         AutoCompleteTextView autoComplete1;         Button btn_Submit;         protected override void OnCreate(Bundle bundle)         {             base.OnCreate(bundle);             //setting the view for the Activity             SetContentView(Resource.Layout.Main);             //Get autoComplete1 AutoCompleteTextView and btn_Hello Button control from the Main.axml Layout.             autoComplete1 = FindViewById<AutoCompleteTextView>(Resource.Id.autoComplete1);             btn_Submit = FindViewById<Button>(Resource.Id.btn_Submit);             //string array used for displayling AutoComplete Suggestion             var names = new string[] {"Anoop","Arjit","Akshay","Ankit","Rakesh"};             //Use ArrayAdapter for filling the View i.e. AutoCompleteTextView with the list of names(Array).             //Use SimpleSpinnerItem(Predefined layout in Android Resources) for displaying the dropdown list             ArrayAdapter adapter = new ArrayAdapter<string>(this,Android.Resource.Layout.SimpleSpinnerItem,names);             autoComplete1.Adapter = adapter;             btn_Submit.Click += btn_Submit_Click;         }         //btn_Submit Click Event         void btn_Submit_Click(object sender, System.EventArgs e)         {             //Checking if autoComplete1.Text is not empty             if (autoComplete1.Text != "")             {                 Toast.MakeText(this, "Name Entered =" + autoComplete1.Text, ToastLength.Short).Show();             }             else             {                 Toast.MakeText(this, "Please Enter Name!", ToastLength.Short).Show();             }         }     } }

Preview:

Method 2:(Using Custom Resources)
In above example, We have used SimpleSpinnerItem for displaying the list in AutoCompleteTextView but we can also create Custom Resouces for displaing the Auto Suggested list.
Let's Add a new Layout(named as ListName.axml) and Drop TextView Control on it. Adjust textColor, textSize, padding etc according to your need.

ListName.axml Code:

<?xml version="1.0" encoding="utf-8"?> <TextView xmlns:android="http://schemas.android.com/apk/res/android"     android:text="Text"     android:layout_width="fill_parent"     android:layout_height="wrap_content"     android:id="@+id/textView1"     android:padding="5dp"     android:textSize="20dp"     android:textColor="@android:color/black" />

Go to Activity1.cs and in ArrayAdapter, use the Custom Layout Resource which we have created. Rest of the code remains same.

ArrayAdapter adapter = new ArrayAdapter<string>(this, Resource.Layout.ListName, names);

Preview:

Hope you like it. Thanks.

[Download Source Code via Google Drive]

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