Merge pull request #566 from irihitech/page

Fix pagination initialization issue.

demo/Ursa.Demo/Pages/PaginationDemo.axaml

@@ -23,6 +23,7 @@
         <u:Pagination
             Name="page"
             PageSizeOptions="10, 20, 50, 100"
+            CurrentPage="5"
             ShowQuickJump="{Binding #quickJumperSelector.IsChecked}"
             ShowPageSizeSelector="{Binding #pageSizeSelector.IsChecked}"
 			Command="{Binding LoadPageCommand}"

src/Ursa/Controls/Pagination/Pagination.cs

@@ -166,7 +166,11 @@ public class Pagination : TemplatedControl
     private static int? CoerceCurrentPage(AvaloniaObject arg1, int? arg2)
     {
         if (arg2 is null) return null;
-        if (arg1 is Pagination p) arg2 = MathHelpers.SafeClamp(arg2.Value, 1, p.PageCount);
+        // Only coerce the value if the pagination is initialized. Otherwise the value will be coerced to default because PageCount is not yet determined.
+        if (arg1 is Pagination { IsInitialized: true } p)
+        {
+            arg2 = MathHelpers.SafeClamp(arg2.Value, 1, p.PageCount);
+        }
         return arg2;
     }
 
@@ -193,6 +197,7 @@ public class Pagination : TemplatedControl
 
     private void OnPageSizeChanged(AvaloniaPropertyChangedEventArgs<int> args)
     {
+        if (!IsInitialized) return;
         var pageCount = TotalCount / args.NewValue.Value;
         var residue = TotalCount % args.NewValue.Value;
         if (residue > 0) pageCount++;
@@ -218,7 +223,8 @@ public class Pagination : TemplatedControl
         LostFocusEvent.AddHandler(OnQuickJumpInputLostFocus, _quickJumpInput);
 
         InitializePanelButtons();
-        UpdateButtonsByCurrentPage(0);
+        CurrentPage = MathHelpers.SafeClamp(CurrentPage ?? 1, 1, PageCount);
+        UpdateButtonsByCurrentPage(CurrentPage);
     }
 
     private void OnQuickJumpInputKeyDown(object? sender, KeyEventArgs e)
@@ -300,16 +306,15 @@ public class Pagination : TemplatedControl
     {
         if (PageSize == 0) return;
         var pageCount = TotalCount / PageSize;
+        var currentPage = CurrentPage;
+        var residue = TotalCount % PageSize;
+        if (residue > 0) pageCount++;
         if (_buttonPanel is null)
         {
             SetCurrentValue(PageCountProperty, pageCount);
             return;
         }
         
-        var currentPage = CurrentPage;
-        var residue = TotalCount % PageSize;
-        if (residue > 0) pageCount++;
-
         if (pageCount <= 7)
         {
             for (var i = 0; i < 7; i++)

tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs

@@ -0,0 +1,435 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Data;
+using Avalonia.Headless.XUnit;
+using Avalonia.Interactivity;
+using Avalonia.Markup.Xaml.MarkupExtensions;
+using Avalonia.Threading;
+using CommunityToolkit.Mvvm.Input;
+using HeadlessTest.Ursa.TestHelpers;
+using Ursa.Controls;
+
+namespace HeadlessTest.Ursa.Controls.PaginationTests;
+
+public class PaginationTests
+{
+    [AvaloniaFact]
+    public void CurrentPage_Can_Be_Initialized()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void CurrentPage_Can_Be_Initialized_With_Another_Initialization_Order()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            TotalCount = 300,
+            PageSize = 50,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Change_TotalCount_Should_Update_PageCount()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        pagination.TotalCount = 500;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(10, pagination.PageCount);
+        Assert.Equal(500, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Change_PageSize_Should_Update_PageCount()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        pagination.PageSize = 100;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(3, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(100, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+    }
+
+    [AvaloniaFact]
+    public void Change_TotalCount_Clamps_Current_Page()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        pagination.TotalCount = 10;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, pagination.PageCount);
+        Assert.Equal(10, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(1, pagination.CurrentPage);
+    }
+
+    [AvaloniaFact]
+    public void CurrentPage_Is_Clamped()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        pagination.CurrentPage = 10;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(6, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void CurrentPage_Is_Clamped_When_PageCount_Changes()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        pagination.TotalCount = 10;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, pagination.PageCount);
+        Assert.Equal(10, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(1, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Click_Next_Button_Should_Increment_CurrentPage()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        nextButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(4, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Click_Previous_Button_Should_Decrement_CurrentPage()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(3, pagination.CurrentPage);
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        previousButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(2, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Previous_Or_Next_Button_Is_Disabled_When_CurrentPage_Is_Min_Or_Max()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 1,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(1, pagination.CurrentPage);
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        Assert.False(previousButton?.IsEnabled);
+        Assert.True(nextButton?.IsEnabled);
+        pagination.CurrentPage = 6;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(6, pagination.PageCount);
+        Assert.Equal(300, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(6, pagination.CurrentPage);
+        Assert.True(previousButton?.IsEnabled);
+        Assert.False(nextButton?.IsEnabled);
+    }
+    
+    [AvaloniaFact]
+    public void TinyPagination_Should_Calculate_PageCount_Correctly()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 1,
+            PageSize = 50,
+            TotalCount = 10,
+            [!StyledElement.ThemeProperty] = new DynamicResourceExtension("TinyPagination")
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, pagination.PageCount);
+        Assert.Equal(10, pagination.TotalCount);
+        Assert.Equal(50, pagination.PageSize);
+        Assert.Equal(1, pagination.CurrentPage);
+    }
+    
+    [AvaloniaFact]
+    public void Click_On_Previews_Or_Next_Triggers_Command()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand(() => count++)
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        previousButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+        nextButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Assert.Equal(2, count);
+        Dispatcher.UIThread.RunJobs();
+    }
+    
+    [AvaloniaFact]
+    public void Click_On_Previews_Or_Next_Triggers_Command_With_Parameter()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand<int>(page => count = page),
+            [!Pagination.CommandParameterProperty] = new Binding(nameof(Pagination.CurrentPage))
+                { RelativeSource = new RelativeSource(RelativeSourceMode.Self) },
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        previousButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(2, count);
+        nextButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(3, count);
+    }
+
+    [AvaloniaFact]
+    public void Buttons_Panel_Is_Correct_Case1()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var buttonsPanel = pagination.GetTemplateChildOfType<Panel>(Pagination.PART_ButtonPanel);
+        Assert.NotNull(buttonsPanel);
+        Assert.Equal(6, buttonsPanel.Children.Count(a => a.IsVisible));
+
+        pagination.TotalCount = 30000;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        
+        var buttons = buttonsPanel.Children.OfType<PaginationButton>().ToList();
+        Assert.Equal(1, buttons[0].Page);
+        Assert.Equal(2, buttons[1].Page);
+        Assert.Equal(3, buttons[2].Page);
+        Assert.Equal(4, buttons[3].Page);
+        Assert.Equal(5, buttons[4].Page);
+        Assert.True(buttons[5].IsFastBackward);
+        Assert.Equal(600, buttons[6].Page);
+        
+        pagination.CurrentPage = 300;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        Assert.Equal(1, buttons[0].Page);
+        Assert.True(buttons[1].IsFastForward);
+        Assert.Equal(299, buttons[2].Page);
+        Assert.Equal(300, buttons[3].Page);
+        Assert.Equal(301, buttons[4].Page);
+        Assert.True(buttons[5].IsFastBackward);
+        Assert.Equal(600, buttons[6].Page);
+        
+        pagination.CurrentPage = 600;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        Assert.Equal(1, buttons[0].Page);
+        Assert.True(buttons[1].IsFastForward);
+        Assert.Equal(596, buttons[2].Page);
+        Assert.Equal(597, buttons[3].Page);
+        Assert.Equal(598, buttons[4].Page);
+        Assert.Equal(599, buttons[5].Page);
+        Assert.Equal(600, buttons[6].Page);
+
+    }
+
+    [AvaloniaFact]
+    public void Button_Panel_Button_Triggers_Command()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand<int>(page => count = page),
+            [!Pagination.CommandParameterProperty] = new Binding(nameof(Pagination.CurrentPage))
+                { RelativeSource = new RelativeSource(RelativeSourceMode.Self) },
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var buttonsPanel = pagination.GetTemplateChildOfType<Panel>(Pagination.PART_ButtonPanel);
+        var buttons = buttonsPanel.Children.OfType<PaginationButton>().ToList();
+        buttons[0].RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+        buttons[1].RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(2, count);
+    }
+
+    [AvaloniaFact]
+    public void Change_CurrentPage_Triggers_Event()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        pagination.CurrentPageChanged += (sender, args) => count++;
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        pagination.CurrentPage = 5;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+    }
+    
+}