radzen-blazor/Radzen.Blazor/ContextMenuService.cs

using Microsoft.AspNetCore.Components;
using Microsoft.AspNetCore.Components.Web;
using System;
using System.Collections.Generic;

namespace Radzen
{
    /// <summary>
    /// Class ContextMenuService. Contains various methods with options to open and close context menus. 
    /// Should be added as scoped service in the application services and RadzenContextMenu should be added in application main layout.
    /// Implements the <see cref="IDisposable" />
    /// </summary>
    /// <seealso cref="IDisposable" />
    /// <example>
    /// <code>
    /// @inject ContextMenuService ContextMenuService
    /// &lt;RadzenButton Text="Show context menu" ContextMenu=@(args => ShowContextMenuWithContent(args)) /&gt;
    /// @code {
    ///     void ShowContextMenuWithContent(MouseEventArgs args) =&gt; ContextMenuService.Open(args, ds =&gt;
    ///       @&lt;RadzenMenu Click="OnMenuItemClick"&gt;
    ///         &lt;RadzenMenuItem Text="Item1" Value="1"&gt;&lt;/RadzenMenuItem&gt;
    ///         &lt;RadzenMenuItem Text="Item2" Value="2"&gt;&lt;/RadzenMenuItem&gt;
    ///         &lt;RadzenMenuItem Text="More items" Value="3"&gt;
    ///             &lt;RadzenMenuItem Text="More sub items" Value="4"&gt;
    ///                 &lt;RadzenMenuItem Text="Item1" Value="5"&gt;&lt;/RadzenMenuItem&gt;
    ///                 &lt;RadzenMenuItem Text="Item2" Value="6"&gt;&lt;/RadzenMenuItem&gt;
    ///             &lt;/RadzenMenuItem&gt;
    ///         &lt;/RadzenMenuItem&gt;
    ///       &lt;/RadzenMenu&gt;);
    /// 
    ///     void OnMenuItemClick(MenuItemEventArgs args)
    ///     {
    ///       Console.WriteLine($"Menu item with Value={args.Value} clicked");
    ///     }
    /// }
    /// </code>
    /// </example>
    public class ContextMenuService : IDisposable
    {
        /// <summary>
        /// Gets or sets the navigation manager.
        /// </summary>
        /// <value>The navigation manager.</value>
        NavigationManager? navigationManager { get; set; }

        /// <summary>
        /// Initializes a new instance of the <see cref="ContextMenuService"/> class.
        /// </summary>
        /// <param name="uriHelper">The URI helper.</param>
        public ContextMenuService(NavigationManager? uriHelper)
        {
            navigationManager = uriHelper;

            if (navigationManager != null)
            {
                navigationManager.LocationChanged += UriHelper_OnLocationChanged;
            }
        }

        /// <summary>
        /// Handles the OnLocationChanged event of the UriHelper control.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="Microsoft.AspNetCore.Components.Routing.LocationChangedEventArgs"/> instance containing the event data.</param>
        private void UriHelper_OnLocationChanged(object? sender, Microsoft.AspNetCore.Components.Routing.LocationChangedEventArgs e)
        {
            this.OnNavigate?.Invoke();
        }

        /// <summary>
        /// Occurs when [on navigate].
        /// </summary>
        public event Action? OnNavigate;

        /// <summary>
        /// Raises the Close event.
        /// </summary>
        public event Action? OnClose;

        /// <summary>
        /// Occurs when [on open].
        /// </summary>
        public event Action<MouseEventArgs, ContextMenuOptions>? OnOpen;

        /// <summary>
        /// Opens the specified arguments.
        /// </summary>
        /// <param name="args">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
        /// <param name="items">The items.</param>
        /// <param name="click">The click.</param>
        public void Open(MouseEventArgs args, IEnumerable<ContextMenuItem> items, Action<MenuItemEventArgs>? click = null)
        {
            var options = new ContextMenuOptions();

            options.Items = items;
            options.Click = click;

            OpenTooltip(args, options);
        }

        /// <summary>
        /// Opens the specified arguments.
        /// </summary>
        /// <param name="args">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
        /// <param name="childContent">Content of the child.</param>
        public void Open(MouseEventArgs args, RenderFragment<ContextMenuService> childContent)
        {
            var options = new ContextMenuOptions();

            options.ChildContent = childContent;

            OpenTooltip(args, options);
        }

        /// <summary>
        /// Opens the tooltip.
        /// </summary>
        /// <param name="args">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
        /// <param name="options">The options.</param>
        private void OpenTooltip(MouseEventArgs args, ContextMenuOptions options)
        {
            OnOpen?.Invoke(args, options);
        }

        /// <summary>
        /// Closes this instance.
        /// </summary>
        public void Close()
        {
            OnClose?.Invoke();
        }

        /// <summary>
        /// Disposes this instance.
        /// </summary>
        public void Dispose()
        {
            if (navigationManager != null)
            {
                navigationManager.LocationChanged -= UriHelper_OnLocationChanged;
            }
            GC.SuppressFinalize(this);
        }
    }

    /// <summary>
    /// Class ContextMenuOptions.
    /// </summary>
    public class ContextMenuOptions
    {
        /// <summary>
        /// Gets or sets the child content.
        /// </summary>
        /// <value>The child content.</value>
        public RenderFragment<ContextMenuService>? ChildContent { get; set; }
        /// <summary>
        /// Gets or sets the items.
        /// </summary>
        /// <value>The items.</value>
        public IEnumerable<ContextMenuItem>? Items { get; set; }

        /// <summary>
        /// Gets or sets the click.
        /// </summary>
        /// <value>The click.</value>
        public Action<MenuItemEventArgs>? Click { get; set; }
    }

    /// <summary>
    /// Class ContextMenu.
    /// </summary>
    public class ContextMenu
    {
        /// <summary>
        /// Gets or sets the options.
        /// </summary>
        /// <value>The options.</value>
        public ContextMenuOptions? Options { get; set; }
        /// <summary>
        /// Gets or sets the mouse event arguments.
        /// </summary>
        /// <value>The mouse event arguments.</value>
        public MouseEventArgs? MouseEventArgs { get; set; }
    }

    /// <summary>
    /// Class ContextMenuItem.
    /// </summary>
    public class ContextMenuItem
    {
        /// <summary>
        /// Gets or sets the text.
        /// </summary>
        /// <value>The text.</value>
        public string? Text { get; set; }
        /// <summary>
        /// Gets or sets the value.
        /// </summary>
        /// <value>The value.</value>
        public object? Value { get; set; }
        /// <summary>
        /// Gets or sets the icon.
        /// </summary>
        /// <value>The icon.</value>
        public string? Icon { get; set; }
        /// <summary>
        /// Gets or sets the icon color.
        /// </summary>
        /// <value>The icon color.</value>
        public string? IconColor { get; set; }
        /// <summary>
        /// Gets or sets the image.
        /// </summary>
        /// <value>The image.</value>
        public string? Image { get; set; }
        /// <summary>
        /// Gets or sets the image style.
        /// </summary>
        /// <value>The image style.</value>
        public string? ImageStyle { get; set; }
        /// <summary>
        /// Gets a value indicating whether this instance is disabled.
        /// </summary>
        /// <value><c>true</c> if this instance is disabled; otherwise, <c>false</c>.</value>
        public bool Disabled { get; set; }
    }
}