When set type:project,how to not ignore the start_date,end_date,duration properties?

i need to custom task’s DOM, but i don’t know how to custom task’s html dom when don’t set type:project

i need to achieve this effect. how can i achieve when not set type:project to use type_renderers?
or is having another good idea?
because i don’t want its start_time and end_time to be effected
image

Hello Yuyang,
If a task has the project type, it ignores the date parameters and depends on the dates of its children:
https://docs.dhtmlx.com/gantt/desktop__task_types.html#projecttasks

There is no way to change how it works.

If you want to set custom dates for the parent tasks, you can set the task type for them.
It is not necessary to use the type_renderers to show triangles at the sides of the parent tasks. There are other ways to do that.

You can do the same by returning custom HTML elements in the leftside_text and rightside_text templates and adding custom styles:
https://docs.dhtmlx.com/gantt/api__gantt_leftside_text_template.html
https://docs.dhtmlx.com/gantt/api__gantt_rightside_text_template.html

Here is an example of how it can be implemented:
https://snippet.dhtmlx.com/hnyckafx

And it is possible to do that by returning only a custom class name in the task_class template and adding the triangles using only custom styles. This approach is explained in the following article that was published yesterday:

Here is the snippet from the article:
https://snippet.dhtmlx.com/ioxpgp6v

In the task_class template, we check if the task has the project type, but you can change it and check if a task has children with the hasChild method:
https://docs.dhtmlx.com/gantt/api__gantt_haschild.html

Also, you need to change the row_height and bar_height parameters if you don’t want the triangles to be displayed outside the parent task rows:
https://docs.dhtmlx.com/gantt/api__gantt_row_height_config.html
https://docs.dhtmlx.com/gantt/api__gantt_bar_height_config.html

Here is the snippet with the custom triangles for the parent tasks:
https://snippet.dhtmlx.com/8g95sfrn