Customizing the custom picker in Xamarin - xamarin

Question

I hope everyone is doing great. Can someone help me on how can I remove the 'cancel' and 'Ok' buttons and allow/raise an event selection if I release the mouse on the item on the screen, Secondly I need help with changing the color of the borderlines and background color? I will appreciate your help thanks.
Picker :
public class BorderlessPickerRenderer : PickerRenderer
{
public static void Init() { }
protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
{
base.OnElementChanged(e);
if (e.OldElement == null)
{
Control.Background = Android.Graphics.Color.Rgb();
string fontFamily = e.NewElement?.FontFamily;
var layoutParams = new MarginLayoutParams(Control.LayoutParameters);
layoutParams.SetMargins(0, 0, 0, 0);
LayoutParameters = layoutParams;
Control.LayoutParameters = layoutParams;
Control.SetPadding(0, 0, 0, 0);
SetPadding(0, 0, 0, 0);
}
}
}

Answer 1

You could use Custon Remderer to define a custom Dialog.
how can I remove the 'cancel' and 'Ok' buttons and allow/raise an event selection if I release the mouse on the item on the screen,
The AlertDialog provides SetNegativeButton event to set the cancel and Ok button. Remove both in the view would be okay. The custom view is a listview. You could use the ItemClick of ListView.
Secondly I need help with changing the color of the borderlines and background color?
You could set the background color of the dialog to change. Add the android:divider to set the borderline color. And add the android:dividerHeight to set the borderline height.
Custom Renderer:
[assembly: ExportRenderer(typeof(Picker), typeof(BorderlessPickerRenderer))]
namespace App15.Droid
{
public class BorderlessPickerRenderer : PickerRenderer
{
AlertDialog listDialog;
string[] items;
public BorderlessPickerRenderer(Context context) : base(context)
{
}
protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
{
base.OnElementChanged(e);
if (Control != null)
{
Control.Click += Control_Click1; ;
}
}
private void Control_Click1(object sender, EventArgs e)
{
Picker model = Element;
items = model.Items.ToArray();
AlertDialog.Builder builder = new AlertDialog.Builder(this.Context);
builder.SetTitle(model.Title ?? "");
//builder.SetNegativeButton("Cancel", (s, a) =>
//{
// Control?.ClearFocus();
// builder = null;
//});
Android.Views.View view = LayoutInflater.From(this.Context).Inflate(Resource.Layout.listview, null);
Android.Widget.ListView listView = view.FindViewById<Android.Widget.ListView>(Resource.Id.listView1);
MyAdapter myAdapter = new MyAdapter(items, Element.SelectedIndex);
listView.Adapter = myAdapter;
listView.ItemClick += ListView_ItemClick;
builder.SetView(view);
listDialog = builder.Create();
listDialog.Window.DecorView.SetBackgroundColor(Android.Graphics.Color.Pink); // set the dialog background color
listDialog.Show();
//Android.Widget.Button button = listDialog.GetButton((int)DialogButtonType.Negative);
//button.Text = "Cancel";
//button.Click += Button_Click;
//button.SetTextColor(Android.Graphics.Color.Blue); // set the button bottom color
}
//private void Button_Click(object sender, EventArgs e)
//{
// listDialog.Dismiss();
// listDialog = null;
//}
private void ListView_ItemClick(object sender, AdapterView.ItemClickEventArgs e)
{
Control.Text = items[e.Position];
Element.SelectedIndex = e.Position;
Console.WriteLine(items[e.Position]);
listDialog.Dismiss();
listDialog = null;
}
class MyAdapter : BaseAdapter
{
private string[] items;
private int selectedIndex;
public MyAdapter(string[] items)
{
this.items = items;
}
public MyAdapter(string[] items, int selectedIndex) : this(items)
{
this.selectedIndex = selectedIndex;
}
public override int Count => items.Length;
public override Java.Lang.Object GetItem(int position)
{
return items[position];
}
public override long GetItemId(int position)
{
return position;
}
public override Android.Views.View GetView(int position, Android.Views.View convertView, ViewGroup parent)
{
if (convertView == null)
{
convertView = LayoutInflater.From(parent.Context).Inflate(Resource.Layout.listview_item, null);
}
TextView textView = convertView.FindViewById<TextView>(Resource.Id.textView1);
textView.Text = items[position];
return convertView;
}
}
}
}
Xaml:
<Picker x:Name="picker" Title="Title" VerticalOptions="CenterAndExpand" >
<Picker.ItemsSource>
<x:Array Type="{x:Type x:String}">
<x:String>Option 1</x:String>
<x:String>Option 2</x:String>
<x:String>Option 3</x:String>
</x:Array>
</Picker.ItemsSource>
</Picker>
listview.xml: You could creat in your Resources/layout in android project.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="#+id/listView1"
android:divider="#android:color/holo_green_light"
android:dividerHeight="2dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
listview_item.xml : You could creat in your Resources/layout in android project.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>