Fsharp xamarin android listview

Learing F# Xamarin.Android ListView

I am learning F# and decided I would start with a Xamarin.Android project that shows a list view.

I decided I would convert the c# example in Mirosoft docs to F#.

https://docs.microsoft.com/en-us/xamarin/android/user-interface/layouts/list-view/

I started with a Xamarin.Android blank project with F# as the language

Please all the instructions for adding xml files.

In MainActivity.fs change the class to inherit from ListActivity instead of Activity

 type MainActivity () =
     inherit ListActivity ()

In the MainActivity.fs we want to change the OnCreate function. First have it create a list of countries.

   override this.OnCreate (bundle) =
     base.OnCreate (bundle)
     let countries = [ "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"]
      // Set our view from the "main" layout resource
     let countyList = new System.Collections.Generic.List<string>()
     countyList.AddRange(countries)

Then we create an ArrayAdapter from the list of countries

  let adapter = new ArrayAdapter(this.BaseContext, Resources.Layout.list_item, countyList)
  this.ListAdapter <- adapter

We should also turn on the ListView’s TextFilter

 this.ListView.TextFilterEnabled <- true

Then finally we can add the eventhandler to show a toast message of the item clicked

  this.ListView.ItemClick.Add(fun (args : AdapterView.ItemClickEventArgs) ->
        let myView = args.View :?> TextView 
        Toast.MakeText(this.BaseContext, myView.Text , ToastLength.Long).Show()

The code is available in GitHub

https://github.com/vb2ae/FSharpAndroidList