How to show only 24hr column in line chart?

问题

I'm working with chart-ios library and i manage to show data in graph like below image.

My Json data is like below. i showing field1+field2+field3 in X and created_at in y axis. this data is for 1 day.

[
{
  "created_at": "2020-05-10T00:01:09Z",
  "field1": 17.57,
  "field2": 56.37,
  "field3": 44.06,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:01:55Z",
  "field1": 17.57,
  "field2": 54.52,
  "field3": 44.62,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:02:40Z",
  "field1": 21.63,
  "field2": 52.7,
  "field3": 51.27,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:03:26Z",
  "field1": 17.15,
  "field2": 54.95,
  "field3": 44.21,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:04:12Z",
  "field1": 15.97,
  "field2": 54.69,
  "field3": 41.36,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:04:57Z",
  "field1": 15.86,
  "field2": 38.58,
  "field3": 36.59,
  "equipment": 3
},
{
  "created_at": "2020-05-10T00:05:43Z",
  "field1": 7.66,
  "field2": 51.6,
  "field3": 45.46,
  "equipment": 3
}
..... 1000 more...
]

What i want is to show x axis label in 1-hour interval. like 11:00, 12:00 and 13:00 , so on. its like fixed 24 hours i want to show, not more than that. but x value count is more than 1000 records.

so how do i do this? can any one point me out in right direction?

Thanks

回答1:

X value need to be Double -> usually I use timeIntervalSince1970
you need a CustomValueFormatter
set xAxis minimum to date with 00:00
set xAxis maximum to date with 00:00 + 1 day
xAxis.granularity = 3600 -> only show label for every hour
chart.setVisibleXRange(minXRange: 5 * 3600, maxXRange: 5 * 3600) -> show only 5 hour range with scroll

check this project: https://github.com/aiwiguna/ExampleCharts/tree/feature/hourly-charts

来源：https://stackoverflow.com/questions/62680758/how-to-show-only-24hr-column-in-line-chart

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ios

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