Grid lines in EJ2 Angular Diagram component

21 Oct 202424 minutes to read

Gridlines are crisscross lines drawn in diagram page like the lines on traditional graph paper. It helps to position the diagram elements on the diagram page.e.

The model’s snapSettings property is used to customize the gridlines and control the snapping behavior in the diagram.

Customize the gridlines visibility

The snapConstraints enables you to show/hide the gridlines. The following code example illustrates how to show or hide gridlines.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel, SnapConstraints,DiagramModule, SnappingService } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings'></ejs-diagram>`,
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        // Display both Horizontal and Vertical gridlines
        constraints:  SnapConstraints.ShowLines
    };
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

NOTE

If you want to enable snapping, then inject snapping module into the diagram.

To show only horizontal/vertical gridlines or to hide gridlines, refer to Constraints.

Appearance

The appearance of the gridlines can be customized by using a set of predefined properties.

  • The horizontalGridLines and the verticalGridLines properties allow to customize the appearance of the horizontal and vertical gridlines respectively.

  • The horizontal gridlines lineColor and lineDashArray properties are used to customizes the line color and line style of the horizontal gridlines.

  • The vertical gridlines lineColor and lineDashArray properties are used to customizes the line color and line style of the vertical gridlines.

The following code example illustrates how to customize the appearance of gridlines.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel, SnapConstraints, DiagramModule, SnappingService } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings'></ejs-diagram>`,
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        // Define the Constraints for gridlines and snapping
        constraints: SnapConstraints.ShowLines,
        // Defines the horizontalGridlines for SnapSettings
        horizontalGridlines: {
            // Sets the line color of gridlines
            lineColor: 'blue',
            // Defines the lineDashArray of gridlines
            lineDashArray: '2 2'
        },
        // Defines the verticalGridlines for SnapSettings
        verticalGridlines: {
            lineColor: 'blue',
            lineDashArray: '2 2'
        }
    };
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Line appearance

Line intervals

Thickness and the space between gridlines can be customized by using horizontal gridlines’s linesInterval and vertical gridlines’s linesInterval properties. In the lines interval collections, values at the odd places are referred as the thickness of lines and values at the even places are referred as the space between gridlines.

The following code example illustrates how to customize the thickness of lines and the line intervals.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel, SnapConstraints, DiagramModule, SnappingService } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings'></ejs-diagram>`,
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        constraints: SnapConstraints.ShowLines,
        horizontalGridlines: {
            // Sets the lineIntervals of Gridlines
            lineIntervals: [1.25, 14, 0.25, 15, 0.25, 15, 0.25, 15, 0.25, 15],
            lineColor: 'blue',
            lineDashArray: '2 2'
        },
        verticalGridlines: {
            // Sets the lineIntervals of Gridlines
            lineIntervals: [1.25, 14, 0.25, 15, 0.25, 15, 0.25, 15, 0.25, 15],
            lineColor: 'blue',
            lineDashArray: '2 2'
        }
    };
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Line interval

Dot grid patterns

The appearance of the grid lines can be changed into dots by settings gridType of snapSettings as Dots. By default, the grid type is Lines.

The following code illustrates how to render grid patterns as Dots.

If you need to enable snapping, then inject snapping module into the diagram.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel, SnapConstraints, DiagramModule, SnappingService } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],
providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings'></ejs-diagram>`,
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        constraints: SnapConstraints.ShowLines,
        gridType: 'Dots',
        // Defines the horizontalGridlines for SnapSettings
        horizontalGridlines: {
          // Sets the line color of gridlines
          lineColor: 'blue',
          // Defines the dot intervals of gridlines
          dotIntervals: [3, 20, 1, 20, 1, 20, 1, 20, 1, 20],
        },
        // Defines the verticalGridlines for SnapSettings
        verticalGridlines: {
          // Defines the dot intervals of gridlines
          dotIntervals: [3, 20, 1, 20, 1, 20],
          // Sets the line color of gridlines
          lineColor: 'blue',
        },
    };
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Dot Grid

Snapping

When you draw, resize, or move a diagram element on the page, you can set it to align or snap to the nearest intersection, regardless of whether the grid is visible.

Snap to lines

This feature allows the diagram objects to snap to the nearest intersection of gridlines while being dragged or resized. This feature enables easier alignment during layout or design.

Snapping to gridlines can be enabled or disabled using the snapConstraints property of the SnapSettings class. The default value is All.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel, SnapConstraints, NodeModel, ShapeStyleModel,DiagramModule, SnappingService } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings' [getNodeDefaults]='getNodeDefaults'>
        <e-nodes>
            <e-node id='node1' [offsetX]=150 [offsetY]=150></e-node>
        </e-nodes>
    </ejs-diagram>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        // Enables the object to snap with both horizontal and Vertical gridlines
        constraints: SnapConstraints.SnapToLines | SnapConstraints.ShowLines
    };
    public getNodeDefaults(node: NodeModel): NodeModel {
        node.height = 100;
        node.width = 100;
        ((node as NodeModel).style as ShapeStyleModel).fill = "#6BA5D7";
        ((node as NodeModel).style as ShapeStyleModel).strokeColor = "White";
        return node;
    }
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Snap to lines

Snap to objects

The snap-to-object feature provides visual cues to assist with aligning and spacing diagram elements. A node can snap to its neighboring objects based on specific alignments, such as the same size and position. These alignments are visually represented by smart guide lines in a cyan shade, with the color code ‘#07EDE1’.

The snapObjectDistance property allows you to define minimum distance between the selected object and the nearest object. By default, the snap object distance is set to 5.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramModule, SnappingService, DiagramComponent, SnapSettingsModel, SnapConstraints, NodeModel, ShapeStyleModel } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings' [getNodeDefaults]='getNodeDefaults'>
        <e-nodes>
            <e-node id='node1' [offsetX]=150 [offsetY]=150></e-node>
            <e-node id='node2' [offsetX]=350 [offsetY]=150></e-node>
        </e-nodes>
    </ejs-diagram>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        // Enable snap to object constraint
        constraints: SnapConstraints.SnapToObject|SnapConstraints.ShowLines,
        // Sets the Snap object distance
        snapObjectDistance: 10,
        // Snap Angle for object
        snapAngle: 10,
        // Set the Snapline color
        snapLineColor: 'red',
    };
    public getNodeDefaults(node: NodeModel): NodeModel {
        node.height = 100;
        node.width = 100;
        ((node as NodeModel).style as ShapeStyleModel).fill = "#6BA5D7";
        ((node as NodeModel).style as ShapeStyleModel).strokeColor = "White";
        return node;
    }
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Snap to object

Snap Angle

The snapAngle property defines the increments by which an object can be rotated within a diagram.

For example, if the snapAngle is set to 15 degrees, an object can only be rotated to angles that are multiples of 15 degrees, such as 15°, 30°, 45°, and so on. This ensures precise angule alignment and consistent object positioning, enhancing the overall design accuracy. By default, the snap angle is set to 5°

The following code example demonstrates how to set the snapAngle property and update it dynamically.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramComponent, SnapSettingsModel,DiagramModule,ShapeStyleModel,SnappingService,NodeModel } from '@syncfusion/ej2-angular-diagrams';

@Component({
  imports: [DiagramModule],
  providers: [SnappingService],
  standalone: true,
  selector: 'app-container',
  // specifies the template string for the diagram component
  template: `
     <b>snapangle </b>
    <input type="number" id="snapAngle" max="360" min="5" value="20" value="snapAngle" (change)="snapAngle($event)" />
    <ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings' [getNodeDefaults] ='getNodeDefaults'>
    <e-nodes>
            <e-node id='node1' [offsetX]=150 [offsetY]=150></e-node>
        </e-nodes>
  </ejs-diagram>
  `, encapsulation: ViewEncapsulation.None
})
export class AppComponent {
  @ViewChild('diagram')
  public diagram?: DiagramComponent;
  public snapSettings: SnapSettingsModel = {
    snapAngle: 20,
  };
  public getNodeDefaults(node: NodeModel | any): NodeModel {
    node.height = 100;
    node.width = 100;
    ((node as NodeModel).style as ShapeStyleModel).fill = '#6BA5D7';
    ((node as NodeModel).style as ShapeStyleModel).strokeColor = 'White';
    return node;
  }
  snapAngle(args: any): void {
    (this.diagram as any).snapSettings.snapAngle = Number(args.target.value);
    (this.diagram as any).dataBind();
  }
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Snap Angle

Snap line color

The snapLineColor property allows you to define the color of the snapline used in the diagram. By customizing the snapline color, you can enhance the visual contrast and visibility of these guides, making it easier to achieve accurate alignment.

This property accepts color values in various formats, such as hexadecimal, RGB, or predefined color names, providing flexibility in how you choose to represent the snaplines in your diagramming application. By default the snap line color is set to '#07EDE1'.

The following code example demonstrates how to set the snapLineColor property and update it dynamically.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import {
  DiagramComponent,SnapSettingsModel,DiagramModule,ShapeStyleModel,SnappingService,NodeModel,} from '@syncfusion/ej2-angular-diagrams';
@Component({
  imports: [DiagramModule],
  providers: [SnappingService],
  standalone: true,
  selector: 'app-container',
  // specifies the template string for the diagram component
  template: `
    <b> Update snap line color</b>
   <input type="color" id="snapLineColor" value="#14AF41" (change)="snapLineColor($event)" />
    <ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings' [getNodeDefaults] ='getNodeDefaults'>
    <e-nodes>
            <e-node id='node1' [offsetX]=150 [offsetY]=150></e-node>
            <e-node id='node2' [offsetX]=350 [offsetY]=150 >
            </e-node>
        </e-nodes>
  </ejs-diagram>
  `,encapsulation: ViewEncapsulation.None
})
export class AppComponent {
  @ViewChild('diagram')
  public diagram?: DiagramComponent;
  public snapSettings: SnapSettingsModel = {
    snapLineColor: '#14AF41',
  };
  public getNodeDefaults(node: NodeModel | any): NodeModel {
    node.height = 100;
    node.width = 100;
    ((node as NodeModel).style as ShapeStyleModel).fill = '#6BA5D7';
    ((node as NodeModel).style as ShapeStyleModel).strokeColor = 'White';
    return node;
  }
  snapLineColor(args: any): void {
    //Update snapLineColor dynamically
    (this.diagram as any).snapSettings.snapLineColor = args.target.value;
    (this.diagram as any).dataBind();
  }
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Customization of snap intervals

By default, the objects are snapped towards the nearest gridline. The gridline or position towards where the diagram object snaps can be customized with the horizontal gridlines’s snapInterval and the vertical gridlines’s snapInterval properties.

import { Component, ViewEncapsulation, ViewChild } from '@angular/core';
import { DiagramModule, SnappingService, DiagramComponent, SnapSettingsModel, SnapConstraints, NodeModel, ShapeStyleModel } from '@syncfusion/ej2-angular-diagrams';

@Component({
imports: [
         DiagramModule
    ],

providers: [SnappingService],
standalone: true,
  selector: "app-container",
  // specifies the template string for the diagram component
  template: `<ejs-diagram #diagram id="diagram" width="100%" height="580px" [snapSettings]='snapSettings' [getNodeDefaults]='getNodeDefaults'>
        <e-nodes>
            <e-node id='node1' [offsetX]=150 [offsetY]=150></e-node>
        </e-nodes>
    </ejs-diagram>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent {
    @ViewChild("diagram")
    public diagram?: DiagramComponent;
    public snapSettings: SnapSettingsModel = {
        horizontalGridlines: {
            // Defines the snap interval for object
            snapIntervals: [20]
        },
        verticalGridlines: {
            snapIntervals: [20]
        },
        constraints: SnapConstraints.All
    };
    public getNodeDefaults(node: NodeModel): NodeModel {
        node.height = 100;
        node.width = 100;
        ((node as NodeModel).style as ShapeStyleModel).fill = "#6BA5D7";
        ((node as NodeModel).style as ShapeStyleModel).strokeColor = "White";
        return node;
    }
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Snap constraints

The snapConstraints property allows you to enable or disable the certain features of the snapping, for detailed information refer to constraints.