Links styling Gantt

Hii. Thank you for the implementation. It looks good. But if i drag the target task beyond source task then the link disappears. How can i fix it? Also
how can i add double click functionality to delete the link when user double clicks on it?

Also can i have two different types of link? Means like from task to task as above but for operation group (black solid line) to tasks different styling?

Hello,

Regarding this:

if i drag the target task beyond source task then the link disappears. How can i fix it?
can i have two different types of link? Means like from task to task as above but for operation group (black solid line) to tasks different styling?

If I understand correctly, you are using the following example: DHTMLX Snippet Tool (using the addTaskLayer method) to render custom links. Unfortunately, this is not a complete solution, but an example that can help make your own solution.

I want to note that to display the “Classic look” you can use rightside_text, leftside_text, task_class templates while maintaining all the functionality of creating / deleting links.
It might look something like this:

gantt.templates.rightside_text = function (start, end, task) {
    if (gantt.hasChild(task.id)) {
        return "<div class='project-right'></div>";
    }
};

gantt.templates.leftside_text = function (start, end, task) {
    if (gantt.hasChild(task.id)) {
        return "<div class='project-left'></div>";
    }
};

gantt.templates.task_class = function (start, end, task) {
    if (gantt.hasChild(task.id)) {
        return 'summary';
    }
}

Styles:

.project-left,
.project-right {
	border-style: solid;
	width: 0px;
	height: 0px;
	border-left: 0px solid transparent;
	border-right: 15px solid transparent;
	border-top: 10px solid #444444;
	border-bottom: 0px;
}

.project-right {
	border-left: 15px solid transparent;
	border-right: 0px solid transparent;
}

.summary .gantt_side_content {
	position: absolute;
	display: inline-block;
    margin-top: 14px;
  	top: 0;
}

.summary .gantt_side_content.gantt_left {
	float: left;
	margin-left: -1px;
    margin-right: -34px;
}

.summary .gantt_side_content.gantt_right {
	float: right;
	margin-right: -1px;
    margin-left: -34px;
}

.summary,
.summary.gantt_project {
	border: 1px solid #444444;
	background: #444444;
}

.gantt_task_line.summary .gantt_task_progress {
	background: #444444;
}

.gantt_task_progress,
.gantt_task_line.gantt_project .gantt_task_progress {
	background-color: rgba(33, 33, 33, 0.17);
}

Here is an example: https://snippet.dhtmlx.com/oaghx0a1

As for:

how can i add double click functionality to delete the link when user double clicks on it?

Please see the following answer: Deleting customized links - #2 by ramil