.NET 8 MAUI iOS：如何在最后点击位置显示图像？

针对你在iOS应用中无法动态更新AbsoluteLayout内自定义光标位置的问题，可通过以下两种思路解决：

思路一：利用数据绑定实现响应式更新 #

将光标图片的AbsoluteLayout.LayoutBounds绑定到ViewModel的属性，通过更新属性值自动刷新UI位置：

1. 在ViewModel中定义用于存储光标坐标的属性（需实现INotifyPropertyChanged接口）：

public class MainViewModel : INotifyPropertyChanged
{
    private double _cursorX;
    private double _cursorY;
    private const double CursorWidth = 32;
    private const double CursorHeight = 32;

    public double CursorX
    {
        get => _cursorX;
        set
        {
            _cursorX = value;
            OnPropertyChanged();
            OnPropertyChanged(nameof(CursorBounds));
        }
    }

    public double CursorY
    {
        get => _cursorY;
        set
        {
            _cursorY = value;
            OnPropertyChanged();
            OnPropertyChanged(nameof(CursorBounds));
        }
    }

    public Rect CursorBounds => new Rect(CursorX - CursorWidth/2, CursorY - CursorHeight/2, CursorWidth, CursorHeight);

    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

2. 在XAML中绑定光标图片的LayoutBounds：

<AbsoluteLayout>
    <!-- 背景图和热区按钮 -->
    <Image Source="background.png" AbsoluteLayout.LayoutBounds="0,0,1,1" AbsoluteLayout.LayoutFlags="All"/>
    
    <!-- 自定义光标 -->
    <Image x:Name="CustomCursor" Source="cursor.png"
           AbsoluteLayout.LayoutBounds="{Binding CursorBounds}"
           AbsoluteLayout.LayoutFlags="None"/>
</AbsoluteLayout>

3. 点击事件中更新ViewModel的坐标：

private void OnBackgroundTapped(object sender, TappedEventArgs e)
{
    var viewModel = BindingContext as MainViewModel;
    var position = e.GetPosition((VisualElement)sender).Result;
    viewModel.CursorX = position.X;
    viewModel.CursorY = position.Y;
}

思路二：直接在代码后台更新LayoutBounds并触发UI刷新 #

如果不使用MVVM，可直接获取光标图片控件的引用，更新LayoutBounds后强制刷新UI：

1. XAML中定义光标图片：

<AbsoluteLayout>
    <Image Source="background.png" AbsoluteLayout.LayoutBounds="0,0,1,1" AbsoluteLayout.LayoutFlags="All" Tapped="OnBackgroundTapped"/>
    <Image x:Name="CustomCursor" Source="cursor.png" AbsoluteLayout.LayoutFlags="None"/>
</AbsoluteLayout>

2. 点击事件中更新位置：

private void OnBackgroundTapped(object sender, TappedEventArgs e)
{
    var position = e.GetPosition((VisualElement)sender).Result;
    const double cursorWidth = 32;
    const double cursorHeight = 32;
    // 设置新的布局边界（让光标中心对准点击位置）
    var newBounds = new Rect(position.X - cursorWidth/2, position.Y - cursorHeight/2, cursorWidth, cursorHeight);
    AbsoluteLayout.SetLayoutBounds(CustomCursor, newBounds);
    // 强制触发控件布局更新
    CustomCursor.LayoutTo(newBounds);
}

关于Cursor类的说明 #

MAUI的Cursor类在iOS平台对自定义光标支持有限，官方推荐通过图片控件+AbsoluteLayout的方式实现自定义光标效果，这也是你当前思路的正确方向。

内容的提问来源于stack exchange，提问作者Dynamixx