added color for each legendEntry(if not set, using default legend color)

[SeRG1k17]

Simple way add color for each legendEntry.
Usage:

    NSMutableArray *legendEntries = [[NSMutableArray alloc] init];
    
    for (int i = 0; i < count; i++)
    {
        UIColor *entryColor = colors[i];
        ChartLegendEntry *entry = [[ChartLegendEntry alloc] initWithLabel:parties[i % parties.count]
                                                               labelColor:entryColor // <-- New property
                                                                     form:ChartLegendFormCircle
                                                                 formSize:8
                                                            formLineWidth:0
                                                        formLineDashPhase:0
                                                      formLineDashLengths:0
                                                                formColor:entryColor];
        
        [legendEntries addObject:entry];
    }
    
    [_chartView.legend setCustomWithEntries: legendEntries];

[codecov-io]

Codecov Report

Merging #2640 into master will increase coverage by <.01%.
The diff coverage is 40%.

@@            Coverage Diff             @@
##           master    #2640      +/-   ##
==========================================
+ Coverage   19.65%   19.65%   +<.01%     
==========================================
  Files         112      112              
  Lines       13717    13721       +4     
==========================================
+ Hits         2696     2697       +1     
- Misses      11021    11024       +3

Impacted Files	Coverage Δ
Source/Charts/Components/LegendEntry.swift	81.81% <100%> (+1.81%)	⬆️
Source/Charts/Renderers/LegendRenderer.swift	42.19% <25%> (-0.27%)	⬇️

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[jjatie]

this should be let legendTextColor...

[SeRG1k17]

@jjatie It's been a long time. I have to double-check it

[jjatie]

this should be let labelTextColor = e.labelColor ?? legendTextColor

[SeRG1k17]

@jjatie It's been a long time. I have to double-check it

[pmairoldi]

closed in favour of #3558