Task disappeared when scrolling

Some of the tasks are not showing but when scrolling they are show/hide (blinking). Basically they are show and hiding when i scroll horizontal scroll.

I think is not necessary to paste all code. see the below.
This is how i set scales
gantt.config.scales = [
{ unit: ‘year’, step: 1, format: ‘%Y’},
{ unit: ‘day’, step: 1, format: ‘%j %D’},
{ unit: ‘hour’, step: 1, format: ‘%g %a’},
{ unit: ‘minute’, step: 35, format: ‘%i’}
];

gantt.config.xml_date = ‘%Y-%m-%d %H:%i’;
gantt.config.min_column_width = 30;
gantt.config.duration_unit =“minute”;
gantt.config.duration_step = 60;
gantt.config.scale_height = 75;

Hello @godfrey,

The config you provide looks correct and shouldn’t occur any issues. I tried to reproduce it (v7.0.5) but tasks shows as expected:
https://recordit.co/6twA1BoQpn

For now, I can’t suggest what is going wrong without details, could you please reproduce the issue in the following snippet(reproduce => click the “Share” button => post here the new link):
http://snippet.dhtmlx.com/5/f9bb234b3
or you can send me a simplified demo, which I will be able to run locally and reproduce the issue?

Best regards,

this is my code

and the output is==>https://prnt.sc/26f5bo1

 gantt.attachEvent(‘onGanttReady’, () => {

      gantt.addTaskLayer({

        renderer: {

          render: (task) => {

            const sizes = gantt.getTaskPosition(task, task.start_date, task.end_date);

            const el = document.createElement(‘div’);

            el.className = ‘deadline’;

            el.style.left = sizes.left + ‘px’;

            el.style.width = sizes.width + ‘px’;

            el.style.top = sizes.top + ‘px’;

            return el;

          },

          onrender: (task, node, view) => {

            ReactDOM.render(

              <GanttTaskText

                iconClick={this.iconClick}

                childIconClick={this.childIconClick}

                task={task}

              />,

              node,

            );

          },

        },

      });

      //using React compo

      gantt.addTaskLayer({

        renderer: {

          render: (task) => {

            var mainDiv = document.createElement(‘div’);

            mainDiv.className = ‘icons’;

            for (var i = 0; i < task.array.length; i++) {

              var elementDate =

                task[‘custom_element_date_’ + [i]] ||

                gantt.date.add(task.start_date, task.array[i].day, ‘day’);

              var sizes = gantt.getTaskPosition(task, elementDate);

              var el = document.createElement(‘div’);

              el.setAttribute(‘data-task’, task.id);

              el.setAttribute(‘data-icon’, [i + 1]);

              if (task.array[i].color === ‘green’) {

                el.className = s.indicator;

              } else {

                el.className = s.red_indicator;

              }

              el.style.left = sizes.left + ‘px’;

              el.style.top = sizes.top + 6 + ‘px’;

              el.style.color = ‘white’;

              el.style.fontSize = ‘10px’;

              mainDiv.appendChild(el);

            }

            return mainDiv;

          },

          onrender: (task, node, view) => {

            for (var i = 0; i < task.array.length; i++) {

              ReactDOM.render(<Tooltip value={task.array[i].num} />, node.childNodes[i]);

            }

          },

        },

      });

    });

Please guide me want I am doing wrong here

Hello Shivam,
I don’t see anything unusual in the code, and I couldn’t reproduce the issue locally.

It is hard to suggest what might be wrong in your case as I don’t see all your code. Please, send me a ready demo with all the necessary files so that I can reproduce the issue locally.