Paging in Blazor TreeGrid Component

11 Oct 202117 minutes to read

Paging provides an option to display Tree Grid data in page segments. To enable paging, set the AllowPaging to true. When paging is enabled, pager component renders at the bottom of the tree grid. Paging options can be configured through the TreeGridPageSettings.

@using TreeGridComponent.Data;
@using Syncfusion.Blazor.TreeGrid;

<SfTreeGrid DataSource="@TreeGridData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1" AllowPaging="true">
    <TreeGridPageSettings PageCount="2" PageSize="2" PageSizeMode="PageSizeMode.Root">
    </TreeGridPageSettings>
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code{
    public List<TreeData.BusinessObject> TreeGridData { get; set; }
    protected override void OnInitialized()
    {
        this.TreeGridData = TreeData.GetSelfDataSource().ToList();
    }
}
namespace TreeGridComponent.Data {

public class TreeData
    {
        public class BusinessObject
        {
            public int TaskId { get; set;}
            public string TaskName { get; set;}
            public int? Duration { get; set;}
            public int? Progress { get; set;}
            public string Priority { get; set;}
            public int? ParentId { get; set;}
        }

        public static List<BusinessObject> GetSelfDataSource()
        {
            List<BusinessObject> BusinessObjectCollection = new List<BusinessObject>();
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 1,TaskName = "Parent Task 1",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 2,TaskName = "Child task 1",Progress = 80,Priority = "Low",ParentId = 1 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 3,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Critical",ParentId = 2 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 4,TaskName = "Child task 3",Duration = 6,Priority = "High",Progress = 77,ParentId = 3 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 5,TaskName = "Parent Task 2",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 6,TaskName = "Child task 1",Duration = 4,Progress = 80,Priority = "Critical",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 7,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Low",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 8,TaskName = "Child task 3",Duration = 6,Progress = 77,Priority = "High",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 9,TaskName = "Child task 4",Duration = 6,Progress = 77,Priority = "Low",ParentId = 5});
            return BusinessObjectCollection;
        }
    }
}

Paging in Blazor TreeGrid

Better performance can be achieved by using tree grid paging to fetch only a pre-defined number of records from the data source.

Page size mode

Two behaviors are available in Tree Grid paging to display certain number of records in a current page. Following are the two types of PageSizeMode property of TreeGridPageSettings.

  • All : This is the default mode. The number of records in a page is based on PageSize property.
  • Root : The number of root nodes or the 0th level records to be displayed per page is based on PageSize property. With PageSizeMode property as Root, only the root level or the 0th level records are considered in records count.

By default, Blazor Tree Grid works with PageSizeMode as Root and to behave as All mode, Adaptor property should be set for Tree Grid SfDataManager.

@using TreeGridComponent.Data;
@using Syncfusion.Blazor.TreeGrid;

<SfTreeGrid DataSource="@TreeGridData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1" AllowPaging="true">
    <TreeGridPageSettings PageCount="2" PageSize="2" PageSizeMode="PageSizeMode.Root">
    </TreeGridPageSettings>
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code{
    public List<TreeData.BusinessObject> TreeGridData { get; set; }
    protected override void OnInitialized()
    {
        this.TreeGridData = TreeData.GetSelfDataSource().ToList();
    }
}
namespace TreeGridComponent.Data {

public class TreeData
    {
        public class BusinessObject
        {
            public int TaskId { get; set;}
            public string TaskName { get; set;}
            public int? Duration { get; set;}
            public int? Progress { get; set;}
            public string Priority { get; set;}
            public int? ParentId { get; set;}
        }

        public static List<BusinessObject> GetSelfDataSource()
        {
            List<BusinessObject> BusinessObjectCollection = new List<BusinessObject>();
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 1,TaskName = "Parent Task 1",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 2,TaskName = "Child task 1",Progress = 80,Priority = "Low",ParentId = 1 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 3,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Critical",ParentId = 2 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 4,TaskName = "Child task 3",Duration = 6,Priority = "High",Progress = 77,ParentId = 3 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 5,TaskName = "Parent Task 2",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 6,TaskName = "Child task 1",Duration = 4,Progress = 80,Priority = "Critical",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 7,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Low",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 8,TaskName = "Child task 3",Duration = 6,Progress = 77,Priority = "High",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 9,TaskName = "Child task 4",Duration = 6,Progress = 77,Priority = "Low",ParentId = 5});
            return BusinessObjectCollection;
        }
    }
}

Changing Page Size Mode in Blazor TreeGrid

Pager with page size dropdown

The pager Dropdown allows to change the number of records in the Tree Grid dynamically. It can be enabled by defining the PageSizes property of TreeGridPageSettings as true.

@using TreeGridComponent.Data;
@using Syncfusion.Blazor.TreeGrid;

<SfTreeGrid DataSource="@TreeGridData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1" AllowPaging="true">
    <TreeGridPageSettings PageCount="2" PageSize="2" PageSizeMode="PageSizeMode.Root" PageSizes="new List<int>() { 2, 5, 10}"></TreeGridPageSettings>
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code{
    public List<TreeData.BusinessObject> TreeGridData { get; set; }
    protected override void OnInitialized()
    {
        this.TreeGridData = TreeData.GetSelfDataSource().ToList();
    }
}
namespace TreeGridComponent.Data {

public class TreeData
    {
        public class BusinessObject
        {
            public int TaskId { get; set;}
            public string TaskName { get; set;}
            public int? Duration { get; set;}
            public int? Progress { get; set;}
            public string Priority { get; set;}
            public int? ParentId { get; set;}
        }

        public static List<BusinessObject> GetSelfDataSource()
        {
            List<BusinessObject> BusinessObjectCollection = new List<BusinessObject>();
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 1,TaskName = "Parent Task 1",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 2,TaskName = "Child task 1",Progress = 80,Priority = "Low",ParentId = 1 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 3,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Critical",ParentId = 2 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 4,TaskName = "Child task 3",Duration = 6,Priority = "High",Progress = 77,ParentId = 3 });
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 5,TaskName = "Parent Task 2",Duration = 10,Progress = 70,Priority = "Critical",ParentId = null});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 6,TaskName = "Child task 1",Duration = 4,Progress = 80,Priority = "Critical",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 7,TaskName = "Child Task 2",Duration = 5,Progress = 65,Priority = "Low",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 8,TaskName = "Child task 3",Duration = 6,Progress = 77,Priority = "High",ParentId = 5});
            BusinessObjectCollection.Add(new BusinessObject() { TaskId = 9,TaskName = "Child task 4",Duration = 6,Progress = 77,Priority = "Low",ParentId = 5});
            return BusinessObjectCollection;
        }
    }
}

Displaying Page Dropdown in Blazor TreeGrid