webapptemplates/BlazorServerApp-NET5/BlaServApp.UI/Components/DataPager.razor.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Components;
using BlaServApp.UI.Components;
using BlaServApp.UI.Data;

namespace BlaServApp.UI.Components
{
    public partial class DataPager
    {
        #region Protected Fields

        protected bool _showLoading = false;

        #endregion Protected Fields

        #region Private Properties

        private int endPage
        {
            get
            {
                int answ = (int)(currPage / numPages) * numPages + numPages;
                answ = answ < LastPage ? answ : LastPage;
                return answ;
            }
        }

        private int LastPage
        {
            get
            {
                return Math.Max((int)Math.Ceiling(totalCount / (double)PageSize), 1);
            }
        }

        private int nextBlock
        {
            get
            {
                int answ = currPage + numPages;
                answ = answ < LastPage ? answ : LastPage;
                return answ;
            }
        }

        private int numPages { get; set; } = 10;

        private int prevBlock
        {
            get
            {
                int answ = currPage - numPages;
                answ = answ > 0 ? answ : 1;
                return answ;
            }
        }

        // calcola un set 1..numPOages centrato sulla pagina corrente...
        private int startPage
        {
            get
            {
                int answ = (int)(currPage / numPages) * numPages;
                answ = answ > 0 ? answ : 1;
                return answ;
            }
        }

        [Inject]
        private Services.BlazorTimer Timer { get; set; }

        #endregion Private Properties

        #region Protected Properties

        protected int _numPage { get; set; } = 1;

        protected int _numRecord { get; set; } = 10;

        protected int percLoading { get; set; } = 0;

        #endregion Protected Properties

        #region Public Properties

        [Parameter]
        public int currPage
        {
            get
            {
                return _numPage;
            }
            set
            {
                bool doReport = !_numPage.Equals(value);
                if (doReport)
                {
                    _numPage = value;
                    reportChangePage();
                }
            }
        }

        [Parameter]
        public EventCallback<int> numPageChanged { get; set; }

        [Parameter]
        public EventCallback<int> numRecordChanged { get; set; }

        [Parameter]
        public int PageSize
        {
            get
            {
                return _numRecord;
            }
            set
            {
                bool doReport = !_numRecord.Equals(value);
                if (doReport)
                {
                    _numRecord = value;
                    reportChange();
                }
            }
        }

        [Parameter]
        public bool showLoading
        {
            get
            {
                return _showLoading;
            }
            set
            {
                if (value)
                {
                    Random random = new Random();
                    percLoading = random.Next(30, 90);
                }
                else
                {
                    percLoading = 5;
                }
                _showLoading = value;
            }
        }

        [Parameter]
        public int totalCount { get; set; } = 0;

        #endregion Public Properties

        #region Private Methods

        private void reportChange()
        {
            numRecordChanged.InvokeAsync(PageSize);
        }

        private void reportChangePage()
        {
            numPageChanged.InvokeAsync(currPage);
        }

        #endregion Private Methods

        #region Protected Methods

        protected void HandlePaginationItemClick(string page)
        {
            currPage = int.Parse(page);
        }

        protected override async Task OnInitializedAsync()
        {
            await Task.Run(() => showLoading = false);
        }

        #endregion Protected Methods
    }
}