Recent articles


How to create a ListView using ListActivity and ListAdapter in Xamarin Android

Posted by seven.srikanth@gmail.com at 13 Nov 2017 in Article


Follow below steps to create a Simple ListView using ListActivity and ListAdapter which will display the List of Countries. When Selected it will give feedback on what is selected.
Steps:
1. Create a New Project ListViewSample. 
2. Create a New file ListViewSample.cs and add the below code to it.
 
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;
namespace ListViewSample
{
    [Activity(Label = "ListViewSample", MainLauncher = true)]
    class ListViewSample : ListActivity
    {
        static readonly string[] countries = new String[] {
    "Afghanistan","Albania","Algeria","American Samoa","Andorra",
    "Angola","Anguilla","Antarctica","Antigua and Barbuda","Argentina",
    "Armenia","Aruba","Australia","Austria","Azerbaijan",
    "Bahrain","Bangladesh","Barbados","Belarus","Belgium",
    "Belize","Benin","Bermuda","Bhutan","Bolivia",
    "Bosnia and Herzegovina","Botswana","Bouvet Island","Brazil","British Indian Ocean Territory",
    "British Virgin Islands","Brunei","Bulgaria","Burkina Faso","Burundi",
    "Cote d'Ivoire","Cambodia","Cameroon","Canada","Cape Verde",
    "Cayman Islands","Central African Republic","Chad","Chile","China",
    "Christmas Island","Cocos (Keeling) Islands","Colombia","Comoros","Congo",
    "Cook Islands","Costa Rica","Croatia","Cuba","Cyprus","Czech Republic",
    "Democratic Republic of the Congo","Denmark","Djibouti","Dominica","Dominican Republic",
    "East Timor","Ecuador","Egypt","El Salvador","Equatorial Guinea","Eritrea",
    "Estonia","Ethiopia","Faeroe Islands","Falkland Islands","Fiji","Finland",
    "Former Yugoslav Republic of Macedonia","France","French Guiana","French Polynesia",
    "French Southern Territories","Gabon","Georgia","Germany","Ghana","Gibraltar",
    "Greece","Greenland","Grenada","Guadeloupe","Guam","Guatemala","Guinea","Guinea-Bissau",
    "Guyana","Haiti","Heard Island and McDonald Islands","Honduras","Hong Kong","Hungary",
    "Iceland","India","Indonesia","Iran","Iraq","Ireland","Israel","Italy","Jamaica",
    "Japan","Jordan","Kazakhstan","Kenya","Kiribati","Kuwait","Kyrgyzstan","Laos",
    "Latvia","Lebanon","Lesotho","Liberia","Libya","Liechtenstein","Lithuania","Luxembourg",
    "Macau","Madagascar","Malawi","Malaysia","Maldives","Mali","Malta","Marshall Islands",
    "Martinique","Mauritania","Mauritius","Mayotte","Mexico","Micronesia","Moldova",
    "Monaco","Mongolia","Montserrat","Morocco","Mozambique","Myanmar","Namibia",
    "Nauru","Nepal","Netherlands","Netherlands Antilles","New Caledonia","New Zealand",
    "Nicaragua","Niger","Nigeria","Niue","Norfolk Island","North Korea","Northern Marianas",
    "Norway","Oman","Pakistan","Palau","Panama","Papua New Guinea","Paraguay","Peru",
    "Philippines","Pitcairn Islands","Poland","Portugal","Puerto Rico","Qatar",
    "Reunion","Romania","Russia","Rwanda","Sqo Tome and Principe","Saint Helena",
    "Saint Kitts and Nevis","Saint Lucia","Saint Pierre and Miquelon",
    "Saint Vincent and the Grenadines","Samoa","San Marino","Saudi Arabia","Senegal",
    "Seychelles","Sierra Leone","Singapore","Slovakia","Slovenia","Solomon Islands",
    "Somalia","South Africa","South Georgia and the South Sandwich Islands","South Korea",
    "Spain","Sri Lanka","Sudan","Suriname","Svalbard and Jan Mayen","Swaziland","Sweden",
    "Switzerland","Syria","Taiwan","Tajikistan","Tanzania","Thailand","The Bahamas",
    "The Gambia","Togo","Tokelau","Tonga","Trinidad and Tobago","Tunisia","Turkey",
    "Turkmenistan","Turks and Caicos Islands","Tuvalu","Virgin Islands","Uganda",
    "Ukraine","United Arab Emirates","United Kingdom",
    "United States","United States Minor Outlying Islands","Uruguay","Uzbekistan",
    "Vanuatu","Vatican City","Venezuela","Vietnam","Wallis and Futuna","Western Sahara",
    "Yemen","Yugoslavia","Zambia","Zimbabwe"
  };
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            ListAdapter = new ListViewAdapter(this, countries);
            ListView.ItemClick += ListView_ItemClick;
        }
        private void ListView_ItemClick(object sender, AdapterView.ItemClickEventArgs e)
        {
            Toast.MakeText(Application, ((TextView)e.View).Text, ToastLength.Short).Show();
        }
    }
}
3. Create a new file ListViewAdapter.cs and add below 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;

namespace ListViewSample
{
    class ListViewAdapter : BaseAdapter<string>
    {
        string[] countries;
        Activity context;

        public ListViewAdapter(Activity context, string[] countries) : base()
        {
            this.context = context;
            this.countries = countries;
        }

        public override string this[int position]
        {
            get { return countries[position]; }
        }

        public override int Count
        {
            get { return countries.Length; }
        }

        public override long GetItemId(int position)
        {
            return position;
        }

        public override View GetView(int position, View convertView, ViewGroup parent)
        {
            View view = convertView;

            if(view == null)
            {
                view = context.LayoutInflater.Inflate(Android.Resource.Layout.SimpleListItem1, null);
            }

            view.FindViewById<TextView>(Android.Resource.Id.Text1).Text = countries[position];
            return view;
        }
    }
}
4. Run the Program now. Thanks, Srikanth

Tags: ListView; ListActivity; ListAdapter;




How to create a ListView using ListActivity and ArrayAdapter in Xamarin Android

Posted by seven.srikanth@gmail.com at 13 Nov 2017 in Article


Follow below steps to create a Simple ListView using ListActivity and ArrayAdapter<String> which will display the List of Countries. When Selected it will give feedback on what is selected.
Steps:
1. Create a Project HelloListView
2. Create a list_item.xml file in Resources\layout folder.
<?xml version="1.0" encoding="utf-8" ?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="10dp"
    android:textSize="16sp">
</TextView>
3. Create a Class with name HelloListView.cs and add below code to it.
using System;
using Android.App;
using Android.Content;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Android.OS;
using System.Collections.Generic;
namespace HelloListView
{
    [Activity(Label = "HelloListView", MainLauncher = true)]
    class HelloListView : ListActivity
    {
        static readonly string[] countries = new String[] {
    "Afghanistan","Albania","Algeria","American Samoa","Andorra",
    "Angola","Anguilla","Antarctica","Antigua and Barbuda","Argentina",
    "Armenia","Aruba","Australia","Austria","Azerbaijan",
    "Bahrain","Bangladesh","Barbados","Belarus","Belgium",
    "Belize","Benin","Bermuda","Bhutan","Bolivia",
    "Bosnia and Herzegovina","Botswana","Bouvet Island","Brazil","British Indian Ocean Territory",
    "British Virgin Islands","Brunei","Bulgaria","Burkina Faso","Burundi",
    "Cote d'Ivoire","Cambodia","Cameroon","Canada","Cape Verde",
    "Cayman Islands","Central African Republic","Chad","Chile","China",
    "Christmas Island","Cocos (Keeling) Islands","Colombia","Comoros","Congo",
    "Cook Islands","Costa Rica","Croatia","Cuba","Cyprus","Czech Republic",
    "Democratic Republic of the Congo","Denmark","Djibouti","Dominica","Dominican Republic",
    "East Timor","Ecuador","Egypt","El Salvador","Equatorial Guinea","Eritrea",
    "Estonia","Ethiopia","Faeroe Islands","Falkland Islands","Fiji","Finland",
    "Former Yugoslav Republic of Macedonia","France","French Guiana","French Polynesia",
    "French Southern Territories","Gabon","Georgia","Germany","Ghana","Gibraltar",
    "Greece","Greenland","Grenada","Guadeloupe","Guam","Guatemala","Guinea","Guinea-Bissau",
    "Guyana","Haiti","Heard Island and McDonald Islands","Honduras","Hong Kong","Hungary",
    "Iceland","India","Indonesia","Iran","Iraq","Ireland","Israel","Italy","Jamaica",
    "Japan","Jordan","Kazakhstan","Kenya","Kiribati","Kuwait","Kyrgyzstan","Laos",
    "Latvia","Lebanon","Lesotho","Liberia","Libya","Liechtenstein","Lithuania","Luxembourg",
    "Macau","Madagascar","Malawi","Malaysia","Maldives","Mali","Malta","Marshall Islands",
    "Martinique","Mauritania","Mauritius","Mayotte","Mexico","Micronesia","Moldova",
    "Monaco","Mongolia","Montserrat","Morocco","Mozambique","Myanmar","Namibia",
    "Nauru","Nepal","Netherlands","Netherlands Antilles","New Caledonia","New Zealand",
    "Nicaragua","Niger","Nigeria","Niue","Norfolk Island","North Korea","Northern Marianas",
    "Norway","Oman","Pakistan","Palau","Panama","Papua New Guinea","Paraguay","Peru",
    "Philippines","Pitcairn Islands","Poland","Portugal","Puerto Rico","Qatar",
    "Reunion","Romania","Russia","Rwanda","Sqo Tome and Principe","Saint Helena",
    "Saint Kitts and Nevis","Saint Lucia","Saint Pierre and Miquelon",
    "Saint Vincent and the Grenadines","Samoa","San Marino","Saudi Arabia","Senegal",
    "Seychelles","Sierra Leone","Singapore","Slovakia","Slovenia","Solomon Islands",
    "Somalia","South Africa","South Georgia and the South Sandwich Islands","South Korea",
    "Spain","Sri Lanka","Sudan","Suriname","Svalbard and Jan Mayen","Swaziland","Sweden",
    "Switzerland","Syria","Taiwan","Tajikistan","Tanzania","Thailand","The Bahamas",
    "The Gambia","Togo","Tokelau","Tonga","Trinidad and Tobago","Tunisia","Turkey",
    "Turkmenistan","Turks and Caicos Islands","Tuvalu","Virgin Islands","Uganda",
    "Ukraine","United Arab Emirates","United Kingdom",
    "United States","United States Minor Outlying Islands","Uruguay","Uzbekistan",
    "Vanuatu","Vatican City","Venezuela","Vietnam","Wallis and Futuna","Western Sahara",
    "Yemen","Yugoslavia","Zambia","Zimbabwe"
  };
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            ListAdapter = new ArrayAdapter<string>(this, Resource.Layout.list_item, countries);
            ListView.ItemClick += ListView_ItemClick;
        }
        private void ListView_ItemClick(object sender, AdapterView.ItemClickEventArgs e)
        {
            Toast.MakeText(Application, ((TextView)e.View).Text, ToastLength.Short).Show();
        }
    }
}
4. Run the Program now.
Thanks,
Srikanth

Tags: ListView;




Creating a Sample form using Relative Layout in Xamarin Android

Posted by seven.srikanth@gmail.com at 12 Nov 2017 in Article


You can use the below code to create a Xamarin form using Relative Layout in Xamarin Android. You have to copy the below code inside Resources\Layout\Main.axml file.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:minWidth="25px"
    android:minHeight="25px">
    <TextView
        android:id="@+id/label"
        android:layout_height="wrap_content"
        android:layout_width="fill_parent"
        android:text="Type your text below"
        android:textSize="20dip"
        android:layout_marginTop="50dip" />
    <EditText
        android:id="@+id/entryField"
        android:layout_height="wrap_content"
        android:layout_width="fill_parent"
        android:layout_below="@id/label" 
        android:background="@android:drawable/editbox_background"/>
    <Button
        android:id="@+id/ok"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:text="OK"
        android:layout_below="@id/entryField"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="10dip" />
    <Button
        android:text="Cancel"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:layout_toLeftOf="@id/ok"
        android:layout_alignTop="@id/ok" />
</RelativeLayout>
Output:
Thanks,
Srikanth

Tags: Sample Form; Relative Layout;