Pickers: Fix ReadOnly not respected in PickerVariant.Static (#12785)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: danielchalmers <7112040+danielchalmers@users.noreply.github.com>

Author: Copilot

src/MudBlazor.UnitTests/Components/DatePickerTests.cs

@@ -1120,6 +1120,23 @@ public async Task CheckReadOnly()
             picker.Date.Should().Be(now);
         }
 
+        [Test]
+        public async Task StaticReadOnly_ShouldNotChangeDate()
+        {
+            var initialDate = new DateTime(2025, 6, 15);
+            var comp = Context.Render<MudDatePicker>(parameters => parameters
+                .Add(p => p.PickerVariant, PickerVariant.Static)
+                .Add(p => p.ReadOnly, true)
+                .Add(p => p.Date, initialDate));
+            var picker = comp.Instance;
+
+            // Try to select a different day - should be blocked by ReadOnly
+            await comp.SelectDateAsync("10");
+
+            // Date should remain unchanged because ReadOnly is true
+            picker.Date.Should().Be(initialDate);
+        }
+
         [Test]
         public async Task CheckDateTimeMinValue()
         {

src/MudBlazor.UnitTests/Components/DateRangePickerTests.cs

@@ -1362,6 +1362,24 @@ public void DateRangePicker_CustomClearIcon_Should_BeRenderedInMarkup()
             comp.Markup.Should().Contain(comp.Instance.ClearIcon);
         }
 
+        [Test]
+        public async Task StaticReadOnly_ShouldNotChangeDateRange()
+        {
+            var initialRange = new DateRange(new DateTime(2025, 6, 10), new DateTime(2025, 6, 20));
+            var comp = Context.Render<MudDateRangePicker>(parameters => parameters
+                .Add(p => p.PickerVariant, PickerVariant.Static)
+                .Add(p => p.ReadOnly, true)
+                .Add(p => p.DateRange, initialRange));
+            var picker = comp.Instance;
+
+            // Try to select different days - should be blocked by ReadOnly
+            await comp.SelectDateAsync("5", firstOccurrence: true);
+            await comp.SelectDateAsync("25", firstOccurrence: true);
+
+            // DateRange should remain unchanged because ReadOnly is true
+            picker.DateRange.Should().Be(initialRange);
+        }
+
         private sealed class DateRangePickerImpl : MudDateRangePicker
         {
             public DateTime StartOfMonth() => GetCalendarStartOfMonth();

src/MudBlazor.UnitTests/Components/TimePickerTests.cs

@@ -380,5 +380,23 @@ public void TimePicker_CustomClearIcon_Should_BeRenderedInMarkup()
 
             comp.Markup.Should().Contain(comp.Instance.ClearIcon);
         }
+
+        [Test]
+        public async Task StaticReadOnly_ShouldNotChangeTime()
+        {
+            var initialTime = new TimeSpan(10, 30, 0);
+            var comp = Context.Render<MudTimePicker>(parameters => parameters
+                .Add(p => p.PickerVariant, PickerVariant.Static)
+                .Add(p => p.ReadOnly, true)
+                .Add(p => p.Time, initialTime));
+            var picker = comp.Instance;
+
+            // Simulate clock stick interaction (as invoked from JS)
+            await comp.InvokeAsync(() => picker.SelectTimeFromStick(5, false));
+
+            // Time should remain unchanged because ReadOnly is true
+            picker.Time.Should().Be(initialTime);
+            picker.TimeIntermediate.Should().Be(initialTime);
+        }
     }
 }

src/MudBlazor/Components/DatePicker/MudDatePicker.cs

@@ -132,6 +132,8 @@ protected override string GetDayClasses(int month, DateTime day)
 
         protected override async Task OnDayClickedAsync(DateTime dateTime)
         {
+            if (GetReadOnlyState())
+                return;
             await FocusAsync();
             _selectedDate = dateTime;
             if (PickerActions == null || AutoClose || PickerVariant == PickerVariant.Static)
@@ -152,6 +154,8 @@ protected override async Task OnDayClickedAsync(DateTime dateTime)
         /// <param name="month"></param>
         protected override async Task OnMonthSelectedAsync(DateTime month)
         {
+            if (GetReadOnlyState())
+                return;
             await FocusAsync();
             PickerMonth = month;
             var nextView = GetNextView();
@@ -191,6 +195,8 @@ protected override async Task OnMonthSelectedAsync(DateTime month)
         /// <param name="year"></param>
         protected override async Task OnYearClickedAsync(int year)
         {
+            if (GetReadOnlyState())
+                return;
             await FocusAsync();
             var current = GetMonthStart(0);
             var culture = GetCulture();

src/MudBlazor/Components/DatePicker/MudDateRangePicker.razor.cs

@@ -430,6 +430,8 @@ protected override string GetDayClasses(int month, DateTime day)
 
         protected override async Task OnDayClickedAsync(DateTime dateTime)
         {
+            if (GetReadOnlyState())
+                return;
             if (_firstDate == null || _secondDate != null)
             {
                 _secondDate = null;

src/MudBlazor/Components/TimePicker/MudTimePicker.razor.cs

@@ -276,6 +276,8 @@ private string GetMinuteString()
 
         private Task UpdateTimeAsync()
         {
+            if (GetReadOnlyState())
+                return Task.CompletedTask;
             TimeIntermediate = new TimeSpan(_timeSet.Hour, _timeSet.Minute, 0);
             if ((PickerVariant == PickerVariant.Static && PickerActions == null) || (PickerActions != null && AutoClose))
             {