Backend API
<div id="treeListDemo">
@(Html.DevExtreme().TreeList()
.ID("treeList")
.DataSource(new JS("employees"))
.KeyExpr("ID")
.ParentIdExpr("Head_ID")
.ExpandedRowKeys(new[] { 1 })
.ShowRowLines(true)
.ShowBorders(true)
.ColumnAutoWidth(true)
.RowDragging(rd => rd
.AllowDropInsideItem(true)
.AllowReordering(true)
.OnDragChange("onDragChange")
.OnReorder("onReorder")
.ShowDragIcons(true)
)
.Columns(columns => {
columns.Add().DataField("Title")
.Caption("Position");
columns.Add().DataField("Full_Name");
columns.Add().DataField("City");
columns.Add().DataField("State");
columns.Add().DataField("Mobile_Phone");
columns.Add().DataField("Hire_Date")
.DataType(GridColumnDataType.Date);
})
)
<div class="options">
<div class="caption">Options</div>
<div class="options-container">
<div class="option">
@(Html.DevExtreme().CheckBox()
.ID("allowDropInside")
.Text("Allow Drop Inside Item")
.Value(true)
.OnValueChanged(@<text>
function(e) {
getTreeList().option("rowDragging.allowDropInsideItem", e.value);
}
</text>)
)
</div>
<div class="option">
@(Html.DevExtreme().CheckBox()
.ID("allowReordering")
.Text("Allow Reordering")
.Value(true)
.OnValueChanged(@<text>
function(e) {
getTreeList().option("rowDragging.allowReordering", e.value);
}
</text>)
)
</div>
<div class="option">
@(Html.DevExtreme().CheckBox()
.ID("showDragIcons")
.Text("Show Drag Icons")
.Value(true)
.OnValueChanged(@<text>
function(e) {
getTreeList().option("rowDragging.showDragIcons", e.value);
}
</text>)
)
</div>
</div>
</div>
</div>
<script>
function onDragChange(e) {
var treeList = e.component,
visibleRows = treeList.getVisibleRows(),
sourceNode = treeList.getNodeByKey(e.itemData.ID),
targetNode = visibleRows[e.toIndex].node;
while (targetNode && targetNode.data) {
if (targetNode.data.ID === sourceNode.data.ID) {
e.cancel = true;
break;
}
targetNode = targetNode.parent;
}
}
function onReorder(e) {
var visibleRows = e.component.getVisibleRows();
if (e.dropInsideItem) {
e.itemData.Head_ID = visibleRows[e.toIndex].key;
} else {
var sourceData = e.itemData,
toIndex = e.fromIndex > e.toIndex ? e.toIndex - 1 : e.toIndex,
targetData = toIndex >= 0 ? visibleRows[toIndex].node.data : null;
if (targetData && e.component.isRowExpanded(targetData.ID)) {
sourceData.Head_ID = targetData.ID;
targetData = null;
} else {
sourceData.Head_ID = targetData ? targetData.Head_ID : e.component.option('rootValue');
}
var sourceIndex = employees.indexOf(sourceData);
employees.splice(sourceIndex, 1);
var targetIndex = employees.indexOf(targetData) + 1;
employees.splice(targetIndex, 0, sourceData);
}
e.component.refresh();
}
function getTreeList() {
return $("#treeList").dxTreeList("instance");
}
</script>
<script src="~/data/employees.js"></script>
using Microsoft.AspNetCore.Mvc;
using DevExtreme.NETCore.Demos.Models.SampleData;
namespace DevExtreme.NETCore.Demos.Controllers {
public class TreeListController : Controller {
public ActionResult LocalReordering() {
return View();
}
}
}
var employees = [{
"ID": 1,
"Head_ID": 0,
"Full_Name": "John Heart",
"Prefix": "Mr.",
"Title": "CEO",
"City": "Los Angeles",
"State": "California",
"Email": "jheart@dx-email.com",
"Skype": "jheart_DX_skype",
"Mobile_Phone": "(213) 555-9392",
"Birth_Date": "1964-03-16",
"Hire_Date": "1995-01-15"
}, {
"ID": 2,
"Head_ID": 1,
"Full_Name": "Samantha Bright",
"Prefix": "Dr.",
"Title": "COO",
"City": "Los Angeles",
"State": "California",
"Email": "samanthab@dx-email.com",
"Skype": "samanthab_DX_skype",
"Mobile_Phone": "(213) 555-2858",
"Birth_Date": "1966-05-02",
"Hire_Date": "2004-05-24"
}, {
"ID": 3,
"Head_ID": 1,
"Full_Name": "Arthur Miller",
"Prefix": "Mr.",
"Title": "CTO",
"City": "Denver",
"State": "Colorado",
"Email": "arthurm@dx-email.com",
"Skype": "arthurm_DX_skype",
"Mobile_Phone": "(310) 555-8583",
"Birth_Date": "1972-07-11",
"Hire_Date": "2007-12-18"
}, {
"ID": 4,
"Head_ID": 1,
"Full_Name": "Robert Reagan",
"Prefix": "Mr.",
"Title": "CMO",
"City": "Bentonville",
"State": "Arkansas",
"Email": "robertr@dx-email.com",
"Skype": "robertr_DX_skype",
"Mobile_Phone": "(818) 555-2387",
"Birth_Date": "1974-09-07",
"Hire_Date": "2002-11-08"
}, {
"ID": 5,
"Head_ID": 1,
"Full_Name": "Greta Sims",
"Prefix": "Ms.",
"Title": "HR Manager",
"City": "Atlanta",
"State": "Georgia",
"Email": "gretas@dx-email.com",
"Skype": "gretas_DX_skype",
"Mobile_Phone": "(818) 555-6546",
"Birth_Date": "1977-11-22",
"Hire_Date": "1998-04-23"
}, {
"ID": 6,
"Head_ID": 3,
"Full_Name": "Brett Wade",
"Prefix": "Mr.",
"Title": "IT Manager",
"City": "Reno",
"State": "Nevada",
"Email": "brettw@dx-email.com",
"Skype": "brettw_DX_skype",
"Mobile_Phone": "(626) 555-0358",
"Birth_Date": "1968-12-01",
"Hire_Date": "2009-03-06"
}, {
"ID": 7,
"Head_ID": 5,
"Full_Name": "Sandra Johnson",
"Prefix": "Mrs.",
"Title": "Controller",
"City": "Beaver",
"State": "Utah",
"Email": "sandraj@dx-email.com",
"Skype": "sandraj_DX_skype",
"Mobile_Phone": "(562) 555-2082",
"Birth_Date": "1974-11-15",
"Hire_Date": "2005-05-11"
}, {
"ID": 8,
"Head_ID": 4,
"Full_Name": "Ed Holmes",
"Prefix": "Dr.",
"Title": "Sales Manager",
"City": "Malibu",
"State": "California",
"Email": "edwardh@dx-email.com",
"Skype": "edwardh_DX_skype",
"Mobile_Phone": "(310) 555-1288",
"Birth_Date": "1973-07-14",
"Hire_Date": "2005-06-19"
}, {
"ID": 9,
"Head_ID": 3,
"Full_Name": "Barb Banks",
"Prefix": "Mrs.",
"Title": "Support Manager",
"City": "Phoenix",
"State": "Arizona",
"Email": "barbarab@dx-email.com",
"Skype": "barbarab_DX_skype",
"Mobile_Phone": "(310) 555-3355",
"Birth_Date": "1979-04-14",
"Hire_Date": "2002-08-07"
}, {
"ID": 10,
"Head_ID": 2,
"Full_Name": "Kevin Carter",
"Prefix": "Mr.",
"Title": "Shipping Manager",
"City": "San Diego",
"State": "California",
"Email": "kevinc@dx-email.com",
"Skype": "kevinc_DX_skype",
"Mobile_Phone": "(213) 555-2840",
"Birth_Date": "1978-01-09",
"Hire_Date": "2009-08-11"
}, {
"ID": 11,
"Head_ID": 5,
"Full_Name": "Cindy Stanwick",
"Prefix": "Ms.",
"Title": "HR Assistant",
"City": "Little Rock",
"State": "Arkansas",
"Email": "cindys@dx-email.com",
"Skype": "cindys_DX_skype",
"Mobile_Phone": "(818) 555-6655",
"Birth_Date": "1985-06-05",
"Hire_Date": "2008-03-24"
}, {
"ID": 12,
"Head_ID": 8,
"Full_Name": "Sammy Hill",
"Prefix": "Mr.",
"Title": "Sales Assistant",
"City": "Pasadena",
"State": "California",
"Email": "sammyh@dx-email.com",
"Skype": "sammyh_DX_skype",
"Mobile_Phone": "(626) 555-7292",
"Birth_Date": "1984-02-17",
"Hire_Date": "2012-02-01"
}, {
"ID": 13,
"Head_ID": 10,
"Full_Name": "Davey Jones",
"Prefix": "Mr.",
"Title": "Shipping Assistant",
"City": "Pasadena",
"State": "California",
"Email": "davidj@dx-email.com",
"Skype": "davidj_DX_skype",
"Mobile_Phone": "(626) 555-0281",
"Birth_Date": "1983-03-06",
"Hire_Date": "2011-04-24"
}, {
"ID": 14,
"Head_ID": 10,
"Full_Name": "Victor Norris",
"Prefix": "Mr.",
"Title": "Shipping Assistant",
"City": "Little Rock",
"State": "Arkansas",
"Email": "victorn@dx-email.com",
"Skype": "victorn_DX_skype",
"Mobile_Phone": "(213) 555-9278",
"Birth_Date": "1986-07-23",
"Hire_Date": "2012-07-23"
}, {
"ID": 15,
"Head_ID": 10,
"Full_Name": "Mary Stern",
"Prefix": "Ms.",
"Title": "Shipping Assistant",
"City": "Beaver",
"State": "Utah",
"Email": "marys@dx-email.com",
"Skype": "marys_DX_skype",
"Mobile_Phone": "(818) 555-7857",
"Birth_Date": "1982-04-08",
"Hire_Date": "2012-08-12"
}, {
"ID": 16,
"Head_ID": 10,
"Full_Name": "Robin Cosworth",
"Prefix": "Mrs.",
"Title": "Shipping Assistant",
"City": "Los Angeles",
"State": "California",
"Email": "robinc@dx-email.com",
"Skype": "robinc_DX_skype",
"Mobile_Phone": "(818) 555-0942",
"Birth_Date": "1981-06-12",
"Hire_Date": "2012-09-01"
}, {
"ID": 17,
"Head_ID": 9,
"Full_Name": "Kelly Rodriguez",
"Prefix": "Ms.",
"Title": "Support Assistant",
"City": "Boise",
"State": "Idaho",
"Email": "kellyr@dx-email.com",
"Skype": "kellyr_DX_skype",
"Mobile_Phone": "(818) 555-9248",
"Birth_Date": "1988-05-11",
"Hire_Date": "2012-10-13"
}, {
"ID": 18,
"Head_ID": 9,
"Full_Name": "James Anderson",
"Prefix": "Mr.",
"Title": "Support Assistant",
"City": "Atlanta",
"State": "Georgia",
"Email": "jamesa@dx-email.com",
"Skype": "jamesa_DX_skype",
"Mobile_Phone": "(323) 555-4702",
"Birth_Date": "1987-01-29",
"Hire_Date": "2012-10-18"
}, {
"ID": 19,
"Head_ID": 9,
"Full_Name": "Antony Remmen",
"Prefix": "Mr.",
"Title": "Support Assistant",
"City": "Boise",
"State": "Idaho",
"Email": "anthonyr@dx-email.com",
"Skype": "anthonyr_DX_skype",
"Mobile_Phone": "(310) 555-6625",
"Birth_Date": "1986-02-19",
"Hire_Date": "2013-01-19"
}, {
"ID": 20,
"Head_ID": 8,
"Full_Name": "Olivia Peyton",
"Prefix": "Mrs.",
"Title": "Sales Assistant",
"City": "Atlanta",
"State": "Georgia",
"Email": "oliviap@dx-email.com",
"Skype": "oliviap_DX_skype",
"Mobile_Phone": "(310) 555-2728",
"Birth_Date": "1981-06-03",
"Hire_Date": "2012-05-14"
}, {
"ID": 21,
"Head_ID": 6,
"Full_Name": "Taylor Riley",
"Prefix": "Mr.",
"Title": "Network Admin",
"City": "San Jose",
"State": "California",
"Email": "taylorr@dx-email.com",
"Skype": "taylorr_DX_skype",
"Mobile_Phone": "(310) 555-7276",
"Birth_Date": "1982-08-14",
"Hire_Date": "2012-04-14"
}, {
"ID": 22,
"Head_ID": 6,
"Full_Name": "Amelia Harper",
"Prefix": "Mrs.",
"Title": "Network Admin",
"City": "Los Angeles",
"State": "California",
"Email": "ameliah@dx-email.com",
"Skype": "ameliah_DX_skype",
"Mobile_Phone": "(213) 555-4276",
"Birth_Date": "1983-11-19",
"Hire_Date": "2011-02-10"
}, {
"ID": 23,
"Head_ID": 6,
"Full_Name": "Wally Hobbs",
"Prefix": "Mr.",
"Title": "Programmer",
"City": "Chatsworth",
"State": "California",
"Email": "wallyh@dx-email.com",
"Skype": "wallyh_DX_skype",
"Mobile_Phone": "(818) 555-8872",
"Birth_Date": "1984-12-24",
"Hire_Date": "2011-02-17"
}, {
"ID": 24,
"Head_ID": 6,
"Full_Name": "Brad Jameson",
"Prefix": "Mr.",
"Title": "Programmer",
"City": "San Fernando",
"State": "California",
"Email": "bradleyj@dx-email.com",
"Skype": "bradleyj_DX_skype",
"Mobile_Phone": "(818) 555-4646",
"Birth_Date": "1988-10-12",
"Hire_Date": "2011-03-02"
}, {
"ID": 25,
"Head_ID": 6,
"Full_Name": "Karen Goodson",
"Prefix": "Miss",
"Title": "Programmer",
"City": "South Pasadena",
"State": "California",
"Email": "kareng@dx-email.com",
"Skype": "kareng_DX_skype",
"Mobile_Phone": "(626) 555-0908",
"Birth_Date": "1987-04-26",
"Hire_Date": "2011-03-14"
}, {
"ID": 26,
"Head_ID": 5,
"Full_Name": "Marcus Orbison",
"Prefix": "Mr.",
"Title": "Travel Coordinator",
"City": "Los Angeles",
"State": "California",
"Email": "marcuso@dx-email.com",
"Skype": "marcuso_DX_skype",
"Mobile_Phone": "(213) 555-7098",
"Birth_Date": "1982-03-02",
"Hire_Date": "2005-05-19"
}, {
"ID": 27,
"Head_ID": 5,
"Full_Name": "Sandy Bright",
"Prefix": "Ms.",
"Title": "Benefits Coordinator",
"City": "Denver",
"State": "Colorado",
"Email": "sandrab@dx-email.com",
"Skype": "sandrab_DX_skype",
"Mobile_Phone": "(818) 555-0524",
"Birth_Date": "1983-09-11",
"Hire_Date": "2005-06-04"
}, {
"ID": 28,
"Head_ID": 6,
"Full_Name": "Morgan Kennedy",
"Prefix": "Mrs.",
"Title": "Graphic Designer",
"City": "San Fernando Valley",
"State": "California",
"Email": "morgank@dx-email.com",
"Skype": "morgank_DX_skype",
"Mobile_Phone": "(818) 555-8238",
"Birth_Date": "1984-07-17",
"Hire_Date": "2012-01-11"
}, {
"ID": 29,
"Head_ID": 28,
"Full_Name": "Violet Bailey",
"Prefix": "Ms.",
"Title": "Jr Graphic Designer",
"City": "La Canada",
"State": "California",
"Email": "violetb@dx-email.com",
"Skype": "violetb_DX_skype",
"Mobile_Phone": "(818) 555-2478",
"Birth_Date": "1985-06-10",
"Hire_Date": "2012-01-19"
}, {
"ID": 30,
"Head_ID": 5,
"Full_Name": "Ken Samuelson",
"Prefix": "Dr.",
"Title": "Ombudsman",
"City": "St. Louis",
"State": "Missouri",
"Email": "kents@dx-email.com",
"Skype": "kents_DX_skype",
"Mobile_Phone": "(562) 555-9282",
"Birth_Date": "1972-09-11",
"Hire_Date": "2009-04-22"
}];
#treeList {
max-height: 440px;
}
.dx-sortable-dragging {
opacity: 0.9
}
.options {
margin-top: 20px;
padding: 20px;
background-color: rgba(191, 191, 191, 0.15);
position: relative;
}
.caption {
font-size: 18px;
font-weight: 500;
}
.option {
margin-top: 10px;
margin-right: 40px;
display: inline-block;
}
.option:last-child {
margin-right: 0;
}
.options-container {
display: flex;
align-items: center;
}
To configure node drag and drop, follow these steps:
-
Allow users to reorder nodes
In the rowDragging object, set the allowReordering property to true. You can use the "Allow Reordering" checkbox under the TreeList to try this property. -
Allow users to change the node hierarchy
Enable the allowDropInsideItem property to allow users to drop one node onto another, thus adding it as the target node's child. If the property is disabled, users can only drop nodes in between others. You can use the "Allow Drop Inside Item" checkbox under the TreeList to try this property. -
Reorder nodes in code
In the onReorder function, change the parent ID of the reordered node and the node's index in the data array. If the node was dropped onto another node, changing the parent ID is sufficient. Refresh() the TreeList after these manipulations. -
Prevent a node from being moved inside its child node
Moving a parent node inside its own child node breaks the hierarchy. Prevent this situation in the onDragChange function. Cycle through the target node's parents. If the parent's and source node's IDs are equal,cancelthe ability to drop the node. -
Show or hide drag icons (optional)
Users use the icons as drag handles. To hide them, set the showDragIcons property to false. In this case, the drag handles are the rows themselves. Use the "Show Drag Icons" checkbox under the TreeList to try this property.