Vue DataGrid - summary
A summary is a grid feature that provides a synopsis of data contained in the grid. A summary consists of several items. A summary item displays a value that is a product of applying an aggregate function to the data of a specific column.
There are two types of summary in DataGrid: group and total. The group summary is calculated on a group of data, which is segregated during grouping. To specify the items of the group summary, declare an array of objects and assign it to the summary.groupItems field.
The total summary is calculated on all data contained in the grid. To specify the items of the total summary, declare an array of objects and assign it to the summary.totalItems field.
calculateCustomSummary
Specifies a custom aggregate function. This function is called for summary items whose summaryType is "custom".
Name | Type | Description |
---|---|---|
value | any |
A column value used to calculate the summary. If you need an entire data object in this field, do not specify the summary item's column property. To display the summary in this case, use the showInColumn property instead. |
totalValue | any |
The resulting summary item's value. |
summaryProcess |
Indicates the stage of the summary item calculation; equals "start", "calculate" or "finalize". |
|
name |
The summary item's name. |
|
groupIndex |
A zero-based group level. Available only when calculating group summary items. |
|
component |
The UI component's instance. |
This is a single function for all custom summary items. Specify a name for each item to identify it in the function.
A summary value calculation is conducted in three stages: start - the totalValue is initialized; calculate - the totalValue is modified; finalize - the totalValue is adjusted. To identify the current stage, check the value of the summaryProcess field that belongs to the function's parameter:
jQuery
$(function() { $("#dataGridContainer").dxDataGrid({ // ... summary: { totalItems: [ { name: "customSummary1", summaryType: "custom" }, { name: "customSummary2", summaryType: "custom" } ], calculateCustomSummary: function(options) { // Calculating "customSummary1" if(options.name == "customSummary1") { switch(options.summaryProcess) { case "start": // Initializing "totalValue" here break; case "calculate": // Modifying "totalValue" here break; case "finalize": // Assigning the final value to "totalValue" here break; } } // Calculating "customSummary2" if(options.name == "customSummary2") { // ... // Same "switch" statement here } } } }); });
Angular
<dx-data-grid ... > <dxo-summary [calculateCustomSummary]="calculateSummary"> <dxi-total-item name="ŃustomSummary1" summaryType="custom"> </dxi-total-item> <dxi-total-item name="ŃustomSummary2" summaryType="custom"> </dxi-total-item> </dxo-summary> </dx-data-grid>
import { Component } from '@angular/core'; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.css'] }) export class AppComponent { calculateSummary(options) { // Calculating "customSummary1" if(options.name == "customSummary1") { switch(options.summaryProcess) { case "start": // Initializing "totalValue" here break; case "calculate": // Modifying "totalValue" here break; case "finalize": // Assigning the final value to "totalValue" here break; } } // Calculating "customSummary2" if(options.name == "customSummary2") { // ... // Same "switch" statement here } }; }
import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { AppComponent } from './app.component'; import { DxDataGridModule } from 'devextreme-angular'; @NgModule({ declarations: [ AppComponent ], imports: [ BrowserModule, DxDataGridModule ], providers: [ ], bootstrap: [AppComponent] }) export class AppModule { }
Vue
<template> <DxDataGrid ... > <DxSummary :calculate-custom-summary="calculateCustomSummary"> <DxTotalItem name="ŃustomSummary1" summary-type="custom" /> <DxTotalItem name="ŃustomSummary2" summary-type="custom" /> </DxSummary> </DxDataGrid> </template> <script> import { DxDataGrid, DxSummary, DxTotalItem } from 'devextreme-vue/data-grid'; export default { components: { DxDataGrid, DxSummary, DxTotalItem }, methods: { calculateCustomSummary(options) { // Calculating "customSummary1" if(options.name == "customSummary1") { switch(options.summaryProcess) { case "start": // Initializing "totalValue" here break; case "calculate": // Modifying "totalValue" here break; case "finalize": // Assigning the final value to "totalValue" here break; } } // Calculating "customSummary2" if(options.name == "customSummary2") { // ... // Same "switch" statement here } }, }, } </script>
React
import React from 'react'; import DataGrid, { Column, TotalItem } from 'devextreme-react/data-grid'; const calculateCustomSummary = (options) => { // Calculating "customSummary1" if(options.name == "customSummary1") { switch(options.summaryProcess) { case "start": // Initializing "totalValue" here break; case "calculate": // Modifying "totalValue" here break; case "finalize": // Assigning the final value to "totalValue" here break; } } // Calculating "customSummary2" if(options.name == "customSummary2") { // ... // Same "switch" statement here } } function App() { return ( <DataGrid ... > <Summary calculateCustomSummary={calculateCustomSummary}> <TotalItem name="customSummary1" summaryType="custom" /> <TotalItem name="customSummary2" summaryType="custom" /> </Summary> </DataGrid> ); } export default App;
You can use the value field to retrieve the column value. If you do not specify a column for which to calculate the summary, the value field contains an entire data object. However, this object misses values from unbound columns calculated in the calculateCellValue function. If you need these values for your custom summary, call the calculateCellValue function from inside calculateCustomSummary, as shown below. In this example, the calculateArea
(calculateCellValue) function creates an unbound column 'Area'. The same function is called from the calculateAreaSummary
(calculateCustomSummary) function to compute the sum of areas for selected rows.
jQuery
const calculateArea = (rowData) => { return rowData.width * rowData.height; } const calculateAreaSummary = (options) => { if (options.name === "AreaSummary") { if (options.summaryProcess === "start") { options.totalValue = 0; } if (options.summaryProcess === "calculate") { if (options.component.isRowSelected(options.value.ID)) { options.totalValue += calculateArea(options.value); } } } } $(function(){ $("#gridContainer").dxDataGrid({ // ... selectedRowKeys: [12, 13], columns: [ "width", "height", { dataField: "Area", calculateCellValue: calculateArea } ], summary: { totalItems: [{ name: "AreaSummary", summaryType: "custom" showInColumn: "Area", displayFormat: "Total Area: {0}", }], calculateCustomSummary: calculateAreaSummary } }); });
Angular
import { Component } from '@angular/core'; // ... export class AppComponent { selectedRows: number[]; constructor() { // ... this.selectedRows = [12, 13]; this.calculateAreaSummary = this.calculateAreaSummary.bind(this); } calculateArea(rowData) { return rowData.width * rowData.height; } calculateAreaSummary(options) { if (options.name === "AreaSummary") { if (options.summaryProcess === "start") { options.totalValue = 0; } if (options.summaryProcess === "calculate") { if (options.component.isRowSelected(options.value.ID)) { options.totalValue += calculateArea(options.value); } } } } }
<dx-data-grid ... [selectedRowKeys]="selectedRows"> <dxi-column dataField="width"></dxi-column> <dxi-column dataField="height"></dxi-column> <dxi-column dataField="Area" [calculateCellValue]="calculateArea"> </dxi-column> <dxo-summary [calculateCustomSummary]="calculateAreaSummary"> <dxi-total-item name="AreaSummary" summaryType="custom" showInColumn="Area" displayFormat="Total Area: {0}"> </dxi-total-item> </dxo-summary> </dx-data-grid>
import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { AppComponent } from './app.component'; import { DxDataGridModule } from 'devextreme-angular'; @NgModule({ declarations: [ AppComponent ], imports: [ BrowserModule, DxDataGridModule ], providers: [ ], bootstrap: [AppComponent] }) export class AppModule { }
Vue
<template> <DxDataGrid ... :selected-row-keys="selectedRowKeys"> <DxColumn data-field="width" /> <DxColumn data-field="height" /> <DxColumn data-field="Area" :calculate-cell-value="calculateArea" /> <DxSummary :calculate-custom-summary="calculateAreaSummary"> <DxTotalItem name="AreaSummary" summary-type="custom" show-in-column="Area" display-format="Total Area: {0}" /> </DxSummary> </DxDataGrid> </template> <script> import { DxDataGrid, DxColumn, DxSummary, DxTotalItem } from 'devextreme-vue/data-grid'; export default { components: { DxDataGrid, DxColumn, DxSummary, DxTotalItem }, data() { return { // ... selectedRowKeys: [12, 13] }; }, methods: { calculateArea(rowData) { return rowData.width * rowData.height; }, calculateAreaSummary(options) { if (options.name === "AreaSummary") { if (options.summaryProcess === "start") { options.totalValue = 0; } if (options.summaryProcess === "calculate") { if (options.component.isRowSelected(options.value.ID)) { options.totalValue += this.calculateArea(options.value); } } } }, }, } </script>
React
import React from 'react'; import DataGrid, { Column, Summary, TotalItem } from 'devextreme-react/data-grid'; const calculateArea = (rowData) => { return rowData.width * rowData.height; } const calculateAreaSummary = (options) => { if (options.name === "AreaSummary") { if (options.summaryProcess === "start") { options.totalValue = 0; } if (options.summaryProcess === "calculate") { if (options.component.isRowSelected(options.value.ID)) { options.totalValue += calculateArea(options.value); } } } } function App() { // ... const selectedRowKeys = [12, 13]; return ( <DataGrid ... selectedRowKeys={selectedRowKeys}> <Column dataField="width" /> <Column dataField="height" /> <Column dataField="Area" calculateCellValue={calculateArea} /> <Summary calculateCustomSummary={calculateAreaSummary}> <TotalItem name="AreaSummary" summaryType="custom" showInColumn="Area" displayFormat="Total Area: {0}" /> </Summary> </DataGrid> ); } export default App;
See Also
groupItems[]
The group summary provides a synopsis of a group of data. Groups of data are formed in the process of grouping. The group summary contains several items. Each item displays a value that is a product of applying an aggregate function to a group of data.
To specify the items of the group summary, declare an array of objects, each of which contains at least two fields: column and summaryType. The column field specifies the identifier of the column that provides data for an aggregate function. The summaryType specifies the aggregate function to be applied. The following code snippet shows how to declare two summary items.
jQuery
$(function () { $("#dataGridContainer").dxDataGrid({ // ... summary: { groupItems: [{ column: "Age", summaryType: "avg" }, { column: "LastName", summaryType: "count" }] } }); });
Angular
<dx-data-grid ... > <dxo-summary> <dxi-group-item column="Age" summaryType="avg"> </dxi-group-item> <dxi-group-item column="LastName" summaryType="count"> </dxi-group-item> </dxo-summary> </dx-data-grid>
import { DxDataGridModule } from "devextreme-angular"; // ... export class AppComponent { // ... } @NgModule({ imports: [ // ... DxDataGridModule ], // ... })
Vue
<template> <DxDataGrid ... > <DxSummary> <DxGroupItem column="Age" summary-type="avg" /> <DxGroupItem column="LastName" summary-type="count" /> </DxSummary> </DxDataGrid> </template> <script> import 'devextreme/dist/css/dx.light.css'; import DxDataGrid, { DxSummary, DxGroupItem } from 'devextreme-vue/data-grid'; export default { components: { DxDataGrid, DxSummary, DxGroupItem }, // ... } </script>
React
import React from 'react'; import 'devextreme/dist/css/dx.light.css'; import DataGrid, { Summary, GroupItem } from 'devextreme-react/data-grid'; export default function App() { return ( <DataGrid ... > <Summary> <GroupItem column="Age" summaryType="avg" /> <GroupItem column="LastName" summaryType="count" /> </Summary> </DataGrid> ); }
A group summary item may be located either in the group row or the group footer. By default, the group row holds all summary items. To locate a summary item in the group footer, set the showInGroupFooter property of this item to true.
See Also
skipEmptyValues
Specifies whether to skip empty strings, null and undefined values when calculating a summary. Does not apply when you use a remote data source.
Specified in the summary object, this property affects all summaries in the grid. In addition, the same property can be specified for an individual summary. It will override the global setting.
Summaries of the count type do not skip empty values regardless of the skipEmptyValues property. However, you can implement a custom summary that skips empty values, as follows:
jQuery
$(function () { $("#dataGridContainer").dxDataGrid({ // ... summary: { totalItems: [{ // ... name: "customSummary1", summaryType: "custom" }], calculateCustomSummary: function (options) { if (options.name == "customSummary1") { if (options.summaryProcess == "start") { options.totalValue = 0; } if (options.summaryProcess == "calculate") { if (e.value) { options.totalValue++; } } } } } }); });
Angular
<dx-data-grid ... > <dxo-summary [calculateCustomSummary]="calculateSummary"> <dxi-total-item summaryType="custom" name="customSummary1"> </dxi-total-item> </dxo-summary> </dx-data-grid>
import { DxDataGridModule } from "devextreme-angular"; // ... export class AppComponent { calculateSummary (options) { if (options.name == "customSummary1") { if (options.summaryProcess == "start") { options.totalValue = 0; } if (options.summaryProcess == "calculate") { if (e.value) { options.totalValue++; } } } }; } @NgModule({ imports: [ // ... DxDataGridModule ], // ... })
Vue
<template> <DxDataGrid ... > <DxSummary :calculate-custom-summary="calculateSummary"> <DxTotalItem summary-type="custom" name="customSummary1" /> </DxSummary> </DxDataGrid> </template> <script> import 'devextreme/dist/css/dx.light.css'; import DxDataGrid, { DxSummary, DxTotalItem } from 'devextreme-vue/data-grid'; export default { components: { DxDataGrid, DxSummary, DxTotalItem }, // ... methods: { calculateSummary (options) { if (options.name == "customSummary1") { if (options.summaryProcess == "start") { options.totalValue = 0; } if (options.summaryProcess == "calculate") { if (e.value) { options.totalValue++; } } } } } } </script>
React
import React, { useCallback } from 'react'; import 'devextreme/dist/css/dx.light.css'; import DataGrid, { Summary, TotalItem } from 'devextreme-react/data-grid'; export default function App() { const calculateSummary = useCallback((options) => { if (options.name == "customSummary1") { if (options.summaryProcess == "start") { options.totalValue = 0; } if (options.summaryProcess == "calculate") { if (e.value) { options.totalValue++; } } } }, []); return ( <DataGrid ... > <Summary ŃalculateCustomSummary={calculateSummary}> <TotalItem summarType="custom" name="customSummary1" /> </Summary> </DataGrid> ); }
texts
Depending on their type, summary items use one of predefined text patterns specified in the summary.texts object. For example, summary items of the "avg" type use the pattern specified by the avg field of the texts object.
By default, a summary item is located in the column that provides data for it. This column is called the "parent column". However, a summary item may be located in any other column or in a group row. To specify text patterns for such summary items, use properties with the OtherColumn addition in their name. For example, summary items of the "avg" type located outside their parent column use the pattern specified by the avgOtherColumn field of the texts object.
When implementing a pattern, you can access the summary item value with applied format using position marker 0. If the summary item is placed outside its parent column, you can also access the caption of the parent column using position marker 1. Place each of these position markers within curly brackets.
totalItems[]
The total summary, which is located in the grid footer, provides a synopsis of all data contained in the grid. It contains several summary items. Each item displays a value that is a product of applying an aggregate function to the data of a specific column.
To specify the items of the total summary, declare an array of objects, each of which contains at least two fields: column and summaryType. The column field specifies the identifier of the column that provides data for an aggregate function. The summaryType specifies the aggregate function to be applied. The following code snippet shows how to declare two summary items.
jQuery
$(function () { $("#dataGridContainer").dxDataGrid({ // ... summary: { totalItems: [{ column: "Age", summaryType: "avg" }, { column: "LastName", summaryType: "count" }] } }); });
Angular
<dx-data-grid ... > <dxo-summary> <dxi-total-item column="Age" summaryType="avg"> </dxi-total-item> <dxi-total-item column="LastName" summaryType="count"> </dxi-total-item> </dxo-summary> </dx-data-grid>
import { DxDataGridModule } from "devextreme-angular"; // ... export class AppComponent { // ... } @NgModule({ imports: [ // ... DxDataGridModule ], // ... })
Vue
<template> <DxDataGrid ... > <DxSummary> <DxTotalItem column="Age" summary-type="avg" /> <DxTotalItem column="LastName" summary-type="count" /> </DxSummary> </DxDataGrid> </template> <script> import 'devextreme/dist/css/dx.light.css'; import DxDataGrid, { DxSummary, DxTotalItem } from 'devextreme-vue/data-grid'; export default { components: { DxDataGrid, DxSummary, DxTotalItem }, // ... } </script>
React
import React from 'react'; import 'devextreme/dist/css/dx.light.css'; import DataGrid, { Summary, TotalItem } from 'devextreme-react/data-grid'; export default function App() { return ( <DataGrid ... > <Summary> <TotalItem column="Age" summaryType="avg" /> <TotalItem column="LastName" summaryType="count" /> </Summary> </DataGrid> ); }
By default, a summary item is placed in the column that provides data for it. If you need to place it in another column, assign the identifier of this column to the showInColumn property.
See Also
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