Legend color behavior

[fglueck]

In a BarAndLineGraph

     'structure'                 => [ 'key' => 'wk_start',
                                       'value' => ['his', 'jvp', 'cur'], 
                                       'axis_text' => 'wk_start',
                                       'colour' => ['c1', 'c3', 'c2', 'c4'],
    ]
 ...

$colours = ['#e0e0e0', '#aaa', '#286aac']; # '#5f95a5'

with data like:
$data = [
['his': 10, 'jvp':13, 'cur':11, 'wk_start': 'avg', 'c2':'#ff0000'],
['his': 10, 'jvp':13, 'cur':11, 'wk_start': '06.09.'],
['his': 10, 'jvp':13, 'cur':11, 'wk_start': '13.09.'],
.... and a lot of more data
]

All bars get the default color #286aac except the first one ('#ff0000')
The legend will take the color from the first bar => '#ff0000'

If I'm not doomed in your source:
In the Colour Class I found the behavior that the priority for the colour will be like:

1. from data struct
2. first element
3. mod (%) ...

But in this case, we have a legend the priority must be

1. global (default) if not set ->
2. data struct ...

I don't found the position in source where the Legend calls the "getColour" Method, but at this position I think it must be handeld by a different Method (not the same for lines or bares) or the Method must be parameterized....

Thanks

[goat1000]

For multi-dataset graphs the legend_type option is set to "dataset", which means only the first entry in each dataset is used for the legend.

For more control you can use the legend_text structured data field to set the text for specific entries (instead of using legend_entries) or set the legend_type to "all" and use the legend_entries_callback option to change them after they are generated.