qhmes/yy-admin-master/YY.Admin/ViewModels/WeightRecord/MixerMaterialPickerDialogViewModel.cs

using HandyControl.Tools.Extension;
using System.Collections.ObjectModel;
using YY.Admin.Core;
using YY.Admin.Core.Entity;
using YY.Admin.Core.Services;

namespace YY.Admin.ViewModels.WeightRecord;

public class MixerMaterialPickerDialogViewModel : BaseViewModel, IDialogResultable<bool>
{
    private readonly IMixerMaterialService _mixerMaterialService;

    private string? _searchCode;
    public string? SearchCode { get => _searchCode; set => SetProperty(ref _searchCode, value); }

    private string? _searchName;
    public string? SearchName { get => _searchName; set => SetProperty(ref _searchName, value); }

    public ObservableCollection<SelectableMixerMaterial> Materials { get; } = new();

    public IReadOnlyList<SelectableMixerMaterial> SelectedMaterials =>
        Materials.Where(m => m.IsSelected).ToList();

    public int SelectedCount => Materials.Count(m => m.IsSelected);

    public string SelectedDisplayText
    {
        get
        {
            var names = Materials.Where(m => m.IsSelected).Select(m => m.Source.MaterialName).ToList();
            return names.Count == 0 ? "请在上方列表中勾选物料，可多选" : string.Join("；", names);
        }
    }

    public bool HasSelectedMaterials => Materials.Any(m => m.IsSelected);

    private bool _result;
    public bool Result { get => _result; set => SetProperty(ref _result, value); }
    public Action? CloseAction { get; set; }

    public DelegateCommand SearchCommand { get; }
    public DelegateCommand ConfirmCommand { get; }
    public DelegateCommand CancelCommand { get; }
    public DelegateCommand ClearSelectionCommand { get; }

    public MixerMaterialPickerDialogViewModel(
        IMixerMaterialService mixerMaterialService,
        IContainerExtension container,
        IRegionManager regionManager) : base(container, regionManager)
    {
        _mixerMaterialService = mixerMaterialService;
        SearchCommand = new DelegateCommand(async () => await LoadAsync());
        ConfirmCommand = new DelegateCommand(Confirm, () => HasSelectedMaterials);
        CancelCommand = new DelegateCommand(() => CloseAction?.Invoke());
        ClearSelectionCommand = new DelegateCommand(ClearSelection);
        _ = LoadAsync();
    }

    private async Task LoadAsync()
    {
        try
        {
            IsLoading = true;
            var selectedIds = Materials.Where(m => m.IsSelected).Select(m => m.Source.Id).ToHashSet();
            var result = await _mixerMaterialService.PageAsync(1, 500,
                materialCode: SearchCode?.Trim(),
                materialName: SearchName?.Trim());
            Materials.Clear();
            foreach (var mat in result.Records)
            {
                var item = new SelectableMixerMaterial(mat);
                if (selectedIds.Contains(mat.Id)) item.IsSelected = true;
                item.SelectionChanged += NotifySelectionChanged;
                Materials.Add(item);
            }
            NotifySelectionChanged();
        }
        catch
        {
            Materials.Clear();
        }
        finally
        {
            IsLoading = false;
        }
    }

    private void NotifySelectionChanged()
    {
        RaisePropertyChanged(nameof(SelectedCount));
        RaisePropertyChanged(nameof(SelectedDisplayText));
        RaisePropertyChanged(nameof(HasSelectedMaterials));
        ConfirmCommand.RaiseCanExecuteChanged();
    }

    private void ClearSelection()
    {
        foreach (var m in Materials) m.IsSelected = false;
    }

    private void Confirm()
    {
        if (!HasSelectedMaterials) return;
        Result = true;
        CloseAction?.Invoke();
    }

    public class SelectableMixerMaterial : System.ComponentModel.INotifyPropertyChanged
    {
        public event System.ComponentModel.PropertyChangedEventHandler? PropertyChanged;
        public event Action? SelectionChanged;

        private bool _isSelected;
        public bool IsSelected
        {
            get => _isSelected;
            set
            {
                if (_isSelected == value) return;
                _isSelected = value;
                PropertyChanged?.Invoke(this, new System.ComponentModel.PropertyChangedEventArgs(nameof(IsSelected)));
                SelectionChanged?.Invoke();
            }
        }

        public MesMixerMaterial Source { get; }
        public SelectableMixerMaterial(MesMixerMaterial source) => Source = source;
    }
}