how to specify the leading and trailing timspan

Gantt
#1

How can I specify the leading and trailing timespan? Currently the leading timespan is one period of date scale and the trailing timespan is also one period of date scale. When using a year as date scale with a sub scale of week or day this results in very much wasted space left and right of my data.
Is there a possibility to specify how much time before first data the gantt should start to render and how much time after last data it should finish rendering?

In the screenshot I marked with a red box the timespan which I like to suppress, because there is no data for that. So this is much wasted space.

gantt_timespan.png2134×796 47.5 KB

#2

Hi,
This behavior should has been corrected in version 3.1
gantt adds one scale column before and after visible tasks. In versions 2.x-3.0 it has used a unit specified in scale_unit config (in this example - year), starting from version 3.1 it uses minimal scale unit for the offset:
docs.dhtmlx.com/gantt/samples/03 … _year.html

Sample:
docs.dhtmlx.com/gantt/api__gantt … onfig.html

#3

So for 2.0 to 3.0 the work around is to set the scale_unit to “month” instead of “year” and make the year a sub scale.

#4

Both solutions (updating to 3.1 as suggested by you) as well as my suggested work around result in the quarters no longer being align to January. I now get a quarter from June to August, because the first month having data is July. So this is ugly.

This could be solved, if you implement a new unit “quarter”, which then begins with a shortened quarter for the empty June followed by a full quarter for July to September and so on.

#5

Hi,
currently year quarters are not supported by gantt, so offset is getting aligned by months.
You can define a quarter unit from the code, it requires defining a two functions:
gantt.date.add_quarter and gantt.date.quarter_start where “quarter” in methods name is the name of the new unit.
Following code seems working (tested on gantt/samples/03_scales/03_full_year.html example):

[code]// defining methods
gantt.date.quarter_start = function(date){
gantt.date.month_start(date);
var m = date.getMonth(),
res_month;

if(m >= 9){
	res_month = 9;
}else if(m >= 6){
	res_month = 6;
}else if(m >= 3){
	res_month = 3
}else{
	res_month = 0
}

date.setMonth(res_month);
return date;

};
gantt.date.add_quarter = function(date, inc){
return gantt.date.add(date, inc*3, “month”);
};

// sample code
gantt.config.scale_unit = “year”;
gantt.config.step = 1;
gantt.config.date_scale = “%Y”;
gantt.config.min_column_width = 50;

gantt.config.scale_height = 90;

var monthScaleTemplate = function(date){
var dateToStr = gantt.date.date_to_str("%M");
var endDate = gantt.date.add(date, 2, “month”);
return dateToStr(date) + " - " + dateToStr(endDate);
};

gantt.config.subscales = [
{unit:“quarter”, step:1, template:monthScaleTemplate},
{unit:“month”, step:1, date:"%M" }
];

gantt.init(“gantt_here”);[/code]