SelectExtended: Fix Initialized Value Doesn't Show on Input When Multiselection & Virtualize (#583)

* SelectExtended: Fix Initialized Value Doesn't Show on Input When Multiselection & Virtualize

* Add Docs Example

Author: mckaragoz

docs/CodeBeam.MudBlazor.Extensions.Docs/Pages/Components/SelectExtended/Examples/SelectExtendedExample9.razor

@@ -0,0 +1,29 @@
+@namespace MudExtensions.Docs.Examples
+
+<MudGrid>
+    <MudItem xs="12" sm="8">
+        <MudStack>
+            <MudSelectExtended @bind-SelectedValues="@_values" Label="Select Overview" Virtualize="true" MultiSelection="_multiselection" Clearable="_clearable">
+                <MudSelectItemExtended Value="@("Foo")" Text="Foo" />
+                <MudSelectItemExtended Value="@("Bar")" Text="Bar" />
+                <MudSelectItemExtended Value="@("Fizz")" Text="Fizz" />
+                <MudSelectItemExtended Value="@("Buzz")" Text="Buzz" />
+            </MudSelectExtended>
+            <MudSelectExtended @bind-SelectedValues="@_values" Label="Data Based" ItemCollection="_collection" Virtualize="true" MultiSelection="_multiselection" Clearable="_clearable" />
+        </MudStack>
+    </MudItem>
+
+    <MudItem xs="12" sm="4">
+        <MudStack Spacing="2">
+            <MudSwitchM3 @bind-Value="_multiselection" Color="Color.Secondary" Label="Multiselection" />
+            <MudSwitchM3 @bind-Value="_clearable" Color="Color.Secondary" Label="Clearable" />
+        </MudStack>
+    </MudItem>
+</MudGrid>
+
+@code {
+    private bool _multiselection = true;
+    private bool _clearable = false;
+    private string[] _collection = new string[] { "Foo", "Bar", "Fizz", "Buzz" };
+    private IEnumerable<string?> _values = new List<string?>() { "Foo" };
+}

docs/CodeBeam.MudBlazor.Extensions.Docs/Pages/Components/SelectExtended/SelectExtendedPage.razor

@@ -33,6 +33,10 @@
     <ExampleCard ComponentName="SelectExtended" ExampleName="SelectExtendedExample5" Title="Chips" Description="Chips can be used as value visualization.">
         <SelectExtendedExample5 />
     </ExampleCard>
+
+    <ExampleCard ComponentName="SelectExtended" ExampleName="SelectExtendedExample9" Title="Virtualization" Description="MudSelectExtended support virtualization with a native parameter.">
+        <SelectExtendedExample9 />
+    </ExampleCard>
 
     <ExampleCard ComponentName="SelectExtended" ExampleName="SelectExtendedExample7" Title="Select All position" Description="Select All can be places next to search.">
         <SelectExtendedExample7 />

src/CodeBeam.MudBlazor.Extensions/Components/SelectExtended/MudSelectExtended.razor

@@ -163,7 +163,7 @@
         <div style="display: none">
             <CascadingValue Value="@this" IsFixed="true">
                 <MudListExtended T="T" @bind-SelectedValue:set="@SetValueAsync" @bind-SelectedValue:get="@ReadValue" @bind-SelectedValues="@SelectedValues" @bind-SelectedItem="@SelectedListItem" @bind-SelectedItems="@SelectedListItems"
-                                 Clickable="true" Color="@Color" Dense="@Dense" ItemCollection="@ItemCollection" Virtualize="@Virtualize" Padding="@EnablePopoverPadding" EnableSelectedItemStyle="@EnableSelectedItemStyle"
+                                 Clickable="true" Color="@Color" Dense="@Dense" ItemCollection="@ItemCollection" Padding="@EnablePopoverPadding" EnableSelectedItemStyle="@EnableSelectedItemStyle"
                                  MultiSelection="@MultiSelection" MultiSelectionComponent="@MultiSelectionComponent" MultiSelectionAlign="@MultiSelectionAlign" SelectAll="@SelectAll" SelectAllPosition="@SelectAllPosition" SelectAllText="@SelectAllText"
                                  CheckedIcon="@CheckedIcon" UncheckedIcon="@UncheckedIcon" IndeterminateIcon="@IndeterminateIcon" SelectValueOnTab="@SelectValueOnTab" Comparer="@Comparer" AddNullItem="@AddNullItem" AddedNullItemText="@AddedNullItemText"
                                  ItemTemplate="@ItemTemplate" ItemSelectedTemplate="@ItemSelectedTemplate" ItemDisabledTemplate="@ItemDisabledTemplate" SearchBox="@SearchBox" SearchBoxAutoFocus="@SearchBoxAutoFocus" SearchFunc="@SearchFunc" SearchBoxPlaceholder="@SearchBoxPlaceholder"

src/CodeBeam.MudBlazor.Extensions/Components/SelectExtended/MudSelectExtended.razor.cs

@@ -773,10 +773,10 @@ protected override void OnInitialized()
             {
                 _selectedValues = new HashSet<T?>(_comparer) { ReadValue };
             }
-            else if (MultiSelection && SelectedValues != null)
+            else if (MultiSelection && SelectedValues != null && SelectedValues.Any())
             {
                 // TODO: Check this line again
-                SetValueAsync(SelectedValues.FirstOrDefault()).CatchAndLog();
+                SetValueAndUpdateTextAsync(SelectedValues.FirstOrDefault()).CatchAndLog();
             }
         }