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Timeline in JavaScript (ES5) Gantt control

In the Gantt control, timeline is used to represent the project duration as individual cells with defined unit and formats.

Timeline view modes

Gantt contains the following in-built timeline view modes:

  • Hour
  • Day
  • Week
  • Month
  • Year

Timescale mode in Gantt can be defined by using timelineViewMode property and also we can define timescale mode of top tier and bottom tier by using topTier.unit and bottomTier.unit properties.

Week timeline mode

In the Week timeline mode, the upper part of the schedule header displays the weeks, whereas the bottom half of the header displays the days. Refer to the following code example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: WeekData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			dependency: 'Predecessor',
            child: 'subtasks'
        },
		timelineSettings: {
			timelineViewMode:'Week'
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Month timeline mode

In the Month timeline mode, the upper part of the schedule header displays the months, whereas the bottom header of the schedule displays its corresponding weeks. Refer to the following code example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: MonthData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
		    timelineViewMode:'Month',
			timelineUnitSize:150
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Year timeline mode

In the Year timeline mode, the upper schedule header displays the years whereas, the bottom header displays its corresponding months. Refer to the following code example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: YearData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
		    timelineViewMode:'Year',
			timelineUnitSize:70
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Day timeline mode

In the Day timeline mode, the upper part of the header displays the days whereas, the bottom schedule header displays its corresponding hours. Refer to the following code example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: DayData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
		    timelineViewMode:'Day'
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Hour timeline mode

An Hour timeline mode tracks the tasks in minutes scale. In this mode, the upper schedule header displays hour scale and the lower schedule header displays its corresponding minutes.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: HourData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
		    timelineViewMode:'Hour'
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Top tier and Bottom tier

Gantt control contains two tier layout in timeline, we can customize the top tier and bottom tier using topTier and bottomTier properties. Timeline tier’s unit can be defined by using unit property and format property was used to define date format of timeline cell and count property was used to define how many unit will be combined as single cell and formatter property was used to define custom method to format the date value of timeline cell.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
		    topTier: {
                    format: 'MMM',
                    unit: 'Month'
                },
                    bottomTier: {
                    unit: 'Day'
				}
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Combining timeline cells

In Gantt, timeline cells in top tier and bottom tier can be combined with number of timeline units, this can be acheived by using topTier.count and bottomTier.count properties. Please refer the below sample.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: Data,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
			timelineUnitSize:100,
		    topTier: {
                   unit: 'Year'
                },
                    bottomTier: {
                    unit: 'Month',
					count:6
                }
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Format value of timeline cell

In the Gantt control, you can format the value of top and bottom timeline cells using the standard date format string or the custom formatter method. This can be done using the topTier.format, topTier.formatter, bottomTier.format and bottomTier.formatter properties. The following example shows how to use the formatter method for timeline cells.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: Data,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
			topTier: {
            unit: 'Month',
            count: 3,
            formatter: (date) => {
                var month = date.getMonth();
                if (month >= 0 && month <=2) {
                return 'Q1';
                } else if(month >= 3 && month <=5) {
                    return 'Q2';
                } else if(month >= 6 && month <=8) {
                    return 'Q3';
                } else {
                    return 'Q4';
                }
            }
	    },
	    bottomTier: {
            unit: 'Month',
            format: 'MMM'
          }
		},
		projectStartDate:new Date('01/04/2019'),
		projectEndDate:new Date('12/30/2019')
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Timeline cell width

In the Gantt control, you can define the width value of timeline cell using the timelineSettings.timelineUnitSize property. This value will be set to the bottom timeline cell, and the width value of top timeline cell will be calculated automatically based on bottom tier cell width using the topTier.unit and timelineSettings.timelineUnitSize properties. Refer to the following example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
            timelineUnitSize:200
        }
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Week start day customization

In the Gantt control, you can customize the week start day using the weekStartDay property. By default, the weekStartDay is set to 0, which specifies the Sunday as a start day of the week. But, you can customize the week start day by using the following code example.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
			timelineViewMode:'Week',
            weekStartDay:3
        }
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Customize automatic timescale update action

In the Gantt control, the schedule timeline will be automatically updated when the tasks date values are updated beyond the project start date and end date ranges. This can be enabled or disabled using the updateTimescaleView property.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			child: 'subtasks'
        },
		timelineSettings: {
            updateTimescaleView:false
        },
		editSettings:{
			allowEditing:true,
			allowTaskbarEditing:true
		}
});
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Zooming

The zooming support provides options to increase or decrease the width of timeline cells and also provides options to change the timeline units dynamically. This support enables you to view the tasks in a project clearly from minute to decade timespan. To enable the zooming features, define the ZoomIn, ZoomOut, and ZoomToFit items to toolbar items collections, and this action can be performed on external actions such as button click using the zoomIn, zoomOut, and fitToProject built-in methods. The following zooming options are available to view the project:

Zoom in

This support is used to increase the timeline width and timeline unit from years to minutes timespan. When the ZoomIn icon was clicked, the timeline cell width is increased when the cell size exceeds the specified range and the timeline unit is changed based on the current zoom levels.

Zoom out

This support is used to increase the timeline width and timeline unit from minutes to years timespan. When the ZoomOut icon was clicked, the timeline cell width is decreased when the cell size falls behind the specified range and the timeline view mode is changed based on the current zooming levels.

Zoom to fit

This support is used to view all the tasks available in a project within available area on the chart part of Gantt. When users click the ZoomToFit icon, then all the tasks are rendered within the available chart container width.

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			dependency: 'Predecessor',
            child: 'subtasks'
        },
        toolbar: ['ZoomIn', 'ZoomOut', 'ZoomToFit'],
        labelSettings: {
            leftLabel: 'TaskName'
        },
        projectStartDate: new Date('03/24/2019'),
        projectEndDate: new Date('04/28/2019')
    });
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Customizing zooming levels

In Gantt, the zoom in and zoom out actions are performed based on the predefined zooming levels in the zoomingLevels property. You can customize the zooming actions by defining the required zooming collection to the zoomingLevels property.

Source
Preview
index.js
index.html
var customZoomingLevels =  [{
                topTier: { unit: 'Month', format: 'MMM, yy', count: 1 },
                bottomTier: { unit: 'Week', format: 'dd', count: 1 }, timelineUnitSize: 33, level: 0,
                timelineViewMode: 'Month', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Month', format: 'MMM, yyyy', count: 1 },
                bottomTier: { unit: 'Week', format: 'dd MMM', count: 1 }, timelineUnitSize: 66, level: 1,
                timelineViewMode: 'Month', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Month', format: 'MMM, yyyy', count: 1 },
                bottomTier: { unit: 'Week', format: 'dd MMM', count: 1 }, timelineUnitSize: 99, level: 2,
                timelineViewMode: 'Month', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Week', format: 'MMM dd, yyyy', count: 1 },
                bottomTier: { unit: 'Day', format: 'd', count: 1 }, timelineUnitSize: 33, level: 3,
                timelineViewMode: 'Week', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Week', format: 'MMM dd, yyyy', count: 1 },
                bottomTier: { unit: 'Day', format: 'd', count: 1 }, timelineUnitSize: 66, level: 4,
                timelineViewMode: 'Week', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Day', format: 'E dd yyyy', count: 1 },
                bottomTier: { unit: 'Hour', format: 'hh a', count: 12 }, timelineUnitSize: 66, level: 5,
                timelineViewMode: 'Day', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
            {
                topTier: { unit: 'Day', format: 'E dd yyyy', count: 1 },
                bottomTier: { unit: 'Hour', format: 'hh a', count: 6 }, timelineUnitSize: 99, level: 6,
                timelineViewMode: 'Day', weekStartDay: 0, updateTimescaleView: true, weekendBackground: null, showTooltip: true
            },
];

var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			dependency: 'Predecessor',
            child: 'subtasks'
        },
        toolbar: ['ZoomIn', 'ZoomOut', 'ZoomToFit'],
        labelSettings: {
            leftLabel: 'TaskName'
        },
		dataBound:function(){
		    ganttChart.zoomingLevels = customZoomingLevels;
		},
		projectStartDate: new Date('03/24/2019'),
        projectEndDate: new Date('04/28/2019')
    });
ganttChart.appendTo('#Gantt');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Zoom action by methods

You can perform the various zoom actions dynamically or on external click action using the following methods:

Source
Preview
index.js
index.html
var ganttChart = new ej.gantt.Gantt({
        dataSource: GanttData,
		height:'450px',
		taskFields: {
            id: 'TaskID',
            name: 'TaskName',
            startDate: 'StartDate',
			duration: 'Duration',
            progress: 'Progress',
			dependency: 'Predecessor',
            child: 'subtasks'
        },
        labelSettings: {
            leftLabel: 'TaskName'
        },
	    projectStartDate: new Date('03/24/2019'),
        projectEndDate: new Date('04/28/2019')
    });
ganttChart.appendTo('#Gantt');

var zoomInBtn= new ej.buttons.Button();
zoomInBtn.appendTo('#zoomIn');

document.getElementById('zoomIn').addEventListener('click', function() {
  ganttChart.zoomIn();
});

var zoomOutBtn= new ej.buttons.Button();
zoomInBtn.appendTo('#zoomOut');

document.getElementById('zoomOut').addEventListener('click', function() {
  ganttChart.zoomOut();
});

var fitToBtn= new ej.buttons.Button();
zoomInBtn.appendTo('#fitToProject');

document.getElementById('fitToProject').addEventListener('click', function() {
  ganttChart.fitToProject();
});
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Gantt</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript Gantt Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
	<link href="https://cdn.syncfusion.com/ej2/material.css" rel="stylesheet" type="text/css">
    
    
<script src="https://cdn.syncfusion.com/ej2/dist/ej2.min.js" type="text/javascript"></script>
<script src="es5-datasource.js" type="text/javascript"></script>
</head>

<body>
       
    
    <div id="container">
	<button id="zoomIn">ZoomIn</button> 
    <button id="zoomOut">ZoomOut</button> 
    <button id="fitToProject">FitToProject</button> 	
        <div id="Gantt"></div>        
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>