ios-charts different plotting activity than MKAndroidChart

[nlabhart]

Please see the attached screenshots for a visual of what is happening. The data set is coming back the from the same source, and is the same data. The data is plotting correctly on the Android implementation (MKAndroidChart), but is not plotting correctly using ios-charts. Is there an obviously setting or view property that I did not set? If you need to see code, I can certainly post it.

ANDROID (Correct Version)

IOS (Incorrect plotting)

[liuxuan30]

First of all, your data seems not the same, android data range is like [70K, 110K], but iOS version is like [90K,110K]

Another is its origin point is higher than android. Double check your chart view's frame on iOS.

[nlabhart]

@liuxuan30 the data I am pulling matches what is in Android (70K, 110K).
This was the first indicator that there was a problem. Also, the frame
doesn't change. It is set in a Xib, and loaded without changing the frame.
However, there is auto layout constraints attached to it. Could this cause
a problem?

[liuxuan30]

It should never be the case that if you feed the data in range [70K,110K] and it draws at the wrong position like [90K,110K], at least not on my side... It's a serious bug and I just cannot believe it right now. You might need to provide the dataSet code and we can try.

For the frame, you can check and compare before/after the autolayout engine calculate the frame. I would suggest start from debugging the frame.

What you can try is after the autolayout engine finalized the frame, you start creating the dataSet and feed the chart.

I just take a look at the ChartsDemo, and it also uses autolayout. Seems putting the code in viewDidLoad is also fine. Anyway, you have to debug it more

[danielgindi]

To me it seems that your problem is the NSNumberFormatter is not configured similarly.

[danielgindi]

You may also want to check if your auto-layout constraints stick to margins or not. Because those "margins" can confuse and cause you to add extra spacing - or have negative extra spacing.

[nlabhart]

The NumberFormatter for the Y Axis is a separate issue. I'll check the
auto-layout constraints to see if that is what is causing the problem. And
I'll check the frame before and after the constraints are applied - I
suspect that is where the issue is, but I'm not sure how to fix it.

[liuxuan30]

@nlabhart I also guess it's autolayout problem, yesterday I met one. Configuring chart view in viewDidLoad and viewDidAppear has slight difference. The one in viewDidAppear is not correct. But it's not my code, so I have to wait for other people to fix.

[nlabhart]

Xuan - is there a function similar to the invalidate() function on
MKAndroidChart? Is the only option setNeedsDisplay?

[danielgindi]

setNeedsDisplay IS invalidate()

‏בתאריך יום חמישי, 6 באוגוסט 2015, Noah Labhart notifications@github.com
כתב:

Xuan - is there a function similar to the invalidate() function on
MKAndroidChart? Is the only option setNeedsDisplay?

On Wed, Aug 5, 2015 at 8:45 PM, Xuan <notifications@github.com
javascript:_e(%7B%7D,'cvml','notifications@github.com');> wrote:

@nlabhart https://github.com/nlabhart I also guess it's autolayout
problem, yesterday I met one. Configuring chart view in viewDidLoad and
viewDidAppear has slight different. The one in viewDidAppear is not
correct. But it it's not my code, so I have to wait for other people to
fix.

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#276 (comment)

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Sincerely,

Noah Labhart
noah@touchtap.io javascript:_e(%7B%7D,'cvml','noah@touchtap.io');
817-988-5253

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#276 (comment)
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[nlabhart]

That is good to know!

What I have found out is that changing the option setZeroEnabled for the
yAxis only changes the yAxis, and not the data. So I need to redraw the
data somehow. Perhaps setNeedsDisplay is the answer.

[danielgindi]

Yes it is. In most functions that work on the data, the chart can't know
about the changes, so you have to tell it.
Sometimes it involves calling "notifyDataSetChanged", sometimes a render is
enough

‏בתאריך יום חמישי, 6 באוגוסט 2015, Noah Labhart notifications@github.com
כתב:

That is good to know!

What I have found out is that changing the option setZeroEnabled for the
yAxis only changes the yAxis, and not the data. So I need to redraw the
data somehow. Perhaps setNeedsDisplay is the answer.

On Thu, Aug 6, 2015 at 7:03 AM, Daniel Cohen Gindi <
notifications@github.com
javascript:_e(%7B%7D,'cvml','notifications@github.com');

wrote:

setNeedsDisplay IS invalidate()

‏בתאריך יום חמישי, 6 באוגוסט 2015, Noah Labhart <
notifications@github.com
javascript:_e(%7B%7D,'cvml','notifications@github.com');>
כתב:

Xuan - is there a function similar to the invalidate() function on
MKAndroidChart? Is the only option setNeedsDisplay?

On Wed, Aug 5, 2015 at 8:45 PM, Xuan <notifications@github.com
javascript:_e(%7B%7D,'cvml','notifications@github.com');
<javascript:_e(%7B%7D,'cvml','notifications@github.com
javascript:_e(%7B%7D,'cvml','notifications@github.com');');>> wrote:

@nlabhart https://github.com/nlabhart I also guess it's autolayout
problem, yesterday I met one. Configuring chart view in viewDidLoad
and
viewDidAppear has slight different. The one in viewDidAppear is not
correct. But it it's not my code, so I have to wait for other people
to
fix.

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#276 (comment)

.

Sincerely,

Noah Labhart
noah@touchtap.io javascript:_e(%7B%7D,'cvml','noah@touchtap.io');
<javascript:_e(%7B%7D,'cvml','noah@touchtap.io
javascript:_e(%7B%7D,'cvml','noah@touchtap.io');');>
817-988-5253

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Reply to this email directly or view it on GitHub
<

#276 (comment)

.

—
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<
#276 (comment)

.

Sincerely,

Noah Labhart
noah@touchtap.io javascript:_e(%7B%7D,'cvml','noah@touchtap.io');
817-988-5253

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#276 (comment)
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[nlabhart]

Figured it out, without setNeedsDisplay or notifyDataHasChanged.

There are two Y axis's in the LineChart I am using - leftAxis and
rightAxis. I had disabled the rightAxis from starting at zero
(startAtZeroEnabled = NO), and disabled the leftAxis entirely (enabled =
NO). However, I tried to set the startAtZeroEnabled on BOTH the left and
right axis - and it started charting properly. So despite the leftAxis
being disabled, the startAtZeroEnabled setting applied.

Thanks for the help!

[liuxuan30]

Have you set your dataSet.axisDependency accordingly? By default it's left. but if you disable leftAxis and enable rightAxis, it should render wrongly I think. startAtZeroEnabled will only affect how the axis range is calculated. if you only have positive data, it's ok to leave it as 'YES' on both axis.

BTW, be careful it you have negative values and disabled startAtZeroEnabled, because I think current calcuation for axis range has bug when dealing with small negative values. Check #166, PR #207, though it's for radar chart. They share the same axis range calcuation in computeAxisValues.

[nlabhart]

Hi @danielgindi would it be possible for you to remove my email address references from your comments? :)