Can't subclass BarChartRenderer due to 'fileprivate' status of many properties

[cegiela]

Thank you for your work on this -- I'd like to customize the appearance of the bars, but can't do it by subclassing the renderer cleanly. It has to be initialized with things that are unavailable to me unless I subclass them and their dependancies, and on it goes. I'd like to just feed the existing properties on BarChartView back into the initialization of the renderer. On a broader note: Really almost all properties should be open in open-source software.

[seenoevo]

I am also running into the same issue, I'm trying to subclass BarChartRenderer and override drawValues, but fileprivate class Buffer and fileprivate var _buffers = [Buffer]() are causing issues.

It's most likely we have to change the source code, at least for BarChartRenderer if we want to subclass it, but I like to hear from @danielgindi @PhilJay @liuxuan30 if there's a better way to not touch the source code.

[seenoevo]

@cegiela resolved it

just re-declare all the fileprivate variables/functions in your subclass, and override the functions as normal:

public class CustomBarChartRenderer: BarChartRenderer
{
    fileprivate class Buffer
    {
        var rects = [CGRect]()
    }
   
    fileprivate var buffers = [Buffer]()
    
    fileprivate var barShadowRectBuffer = CGRect()
    
    override public func initBuffers()

   ...
}

[cegiela]

Thanks @seenoevo, but then how do you make an instance of CustomBarChartRenderer with all the required parameters? Did you get that figured out?

[seenoevo]

@cegiela I think I realized what you're saying:

here's what you do:

The CustomBarChartRenderer, a subclass of BarChartRenderer has the following in its parameters:

CustomBarChartRenderer(dataProvider: BarChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)

just pass in your BarChartView's object member variables like so:

var barChartView = BarChartView()
....
let customRenderer = CustomBarChartRenderer(dataProvider: barChartView,
                                                        animator: barChartView.chartAnimator,
                                                        viewPortHandler: barChartView.viewPortHandler)

[aelam]

I have the same problem So I copy the whole buffer class in my sub bar chart class 发自我的 iPhone

…

在 2017年8月19日，下午6:28，seenoevo ***@***.***> 写道： I am also fixing the same issue, I'm trying to subclass BarChartRenderer and override drawValues, but fileprivate class Buffer and fileprivate var _buffers = [Buffer](). It's most likely we have to change the source at least for BarChartRenderer if we want to subclass it, but I like to hear from @danielgindi @PhilJay @liuxuan30 if there's a better to not touch the source code. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[seenoevo]

@aelam yup that is the way to do it since it's declared as fileprivate in the parent class

[liuxuan30]

fileprivate is something private if you really need to override, just modify them to interval and build the library on your side. Redeclare in your child class also works (may introduce code duplication)