Combobox Fix Multiselection CheckBox Click and Initial MultiSelection Values Show Empty Value on MultiSelection Change (#220)

Author: mckaragoz

CodeBeam.MudBlazor.Extensions.UnitTests/Components/ComboboxTests.cs

@@ -139,17 +139,17 @@ public async Task Combobox_ValueChangeEventCountTest_MultiSelection()
             var combobox = comp.FindComponent<MudComboBox<string>>();
 
             comp.Instance.ValueChangeCount.Should().Be(0);
-            comp.Instance.ValuesChangeCount.Should().Be(1);
+            comp.Instance.ValuesChangeCount.Should().Be(0);
 
             await comp.InvokeAsync(() => combobox.SetParam("SelectedValues", new HashSet<string>() { "1" }));
             comp.WaitForAssertion(() => comp.Instance.ValueChangeCount.Should().Be(0));
-            comp.WaitForAssertion(() => comp.Instance.ValuesChangeCount.Should().Be(2));
+            comp.WaitForAssertion(() => comp.Instance.ValuesChangeCount.Should().Be(1));
 
 
             // Setting same value should not fire events
             await comp.InvokeAsync(() => combobox.SetParam("SelectedValues", new HashSet<string>() { "1" }));
             comp.WaitForAssertion(() => comp.Instance.ValueChangeCount.Should().Be(0));
-            comp.Instance.ValuesChangeCount.Should().Be(2);
+            comp.Instance.ValuesChangeCount.Should().Be(1);
         }
 
         /// <summary>

CodeBeam.MudBlazor.Extensions/Components/ComboBox/MudComboBox.razor.cs

@@ -429,7 +429,15 @@ protected async Task SyncMultiselectionValues(bool singleToMultiselection)
                 }
                 else
                 {
-                    SelectedValues = new HashSet<T>() { Value };
+                    if (Value is string && string.IsNullOrEmpty(Converter.Set(Value)))
+                    {
+                        SelectedValues = new HashSet<T>();
+                    }
+                    else
+                    {
+                        SelectedValues = new HashSet<T>() { Value };
+                    }
+                    
                 }
                 await SelectedValuesChanged.InvokeAsync(_selectedValues);
             }
@@ -650,6 +658,7 @@ protected override void OnParametersSet()
             _allSelected = GetAllSelectedState();
         }
 
+        bool _firstRendered = false;
         T _oldValue;
         bool _oldMultiselection = false;
         protected override async Task OnParametersSetAsync()
@@ -658,7 +667,10 @@ protected override async Task OnParametersSetAsync()
             UpdateIcon();
             if (MultiSelection != _oldMultiselection)
             {
-                await SyncMultiselectionValues(MultiSelection);
+                if (_firstRendered == true)
+                {
+                    await SyncMultiselectionValues(MultiSelection);
+                }
                 ForceRenderItems();
                 if (MultiSelection == true)
                 {
@@ -714,6 +726,7 @@ protected override async Task OnAfterRenderAsync(bool firstRender)
                 _keyInterceptor.KeyDown += HandleKeyDown;
                 _keyInterceptor.KeyUp += HandleKeyUp;
                 await UpdateDataVisualiserTextAsync();
+                _firstRendered = true;
                 StateHasChanged();
             }
             //Console.WriteLine("Select rendered");
@@ -1095,6 +1108,10 @@ public async Task BeginValidatePublic()
             if (Items?.Select(x => x.Value).Contains(item.Value) == false)
             {
                 Items.Add(item);
+                if (MultiSelection == true && SelectedValues.Contains(item.Value))
+                {
+                    item.Selected = true;
+                }
                 result = true;
             }
             return result;

CodeBeam.MudBlazor.Extensions/Components/ComboBox/MudComboBoxItem.razor

@@ -7,7 +7,7 @@
 
     @if (MudComboBox != null && MudComboBox.MultiSelection == true && MudComboBox.ShowCheckbox == true)
     {
-        <MudCheckBox Class="me-4" Color="@MudComboBox.Color" Disabled="@Disabled" @bind-Checked="Selected" @onclick="OnClickHandler" Dense="true" />
+        <MudCheckBox Class="me-4" Color="@MudComboBox.Color" Disabled="@Disabled" @bind-Checked="Selected" @onclick="HandleOnClick" Dense="true" />
     }
 
     <MudText Typo="GetTypo()">

ComponentViewer.Docs/Pages/Examples/ComboboxExample3.razor

@@ -29,7 +29,7 @@
 
 @code {
     string _value;
-    IEnumerable<string> _selectedValues;
+    IEnumerable<string> _selectedValues = new HashSet<string>() { "Harry Potter", "Ron Weasley" };
     Dense _dense = Dense.Standard;
     Color _color = Color.Primary;
     bool _selectAll;