Highcharts 图表中图例显示状态存储的功能设计详解

{
"chart_1":{
"legend_1":true,
"legend_2":true,
"legend_3":true,
"legend_4":true,
"legend_5":true,
"legend_6":true,
"legend_7":false,
"legend_8":false
},
"chart_2":{
"legend_1":true,
"legend_2":true,
"legend_3":true,
"legend_4":true,
"legend_5":true
},
"chart_3":{
"legend_1":true,
"legend_2":true,
"legend_3":true,
"legend_4":true
},
"chart_3":{
"legend_1":true,
"legend_2":true,
"legend_3":true,
"legend_4":true,
"legend_5":true,
"legend_6":true,
"legend_7":true
}
}

{
"chart_1": 15,
"chart_2": 31,
"chart_3": 127,
"chart_3": 252
}

public const BITMAP_INDEXES_BY_LEGEND_IDENTIFIER_BY_CHART_NAME = [
'chart_1' => [
'legend_1' => 7,
'legend_2' => 6,
'legend_3' => 5,
'legend_4' => 4,
'legend_5' => 3,
'legend_6' => 2,
'legend_7' => 1,
'legend_8' => 0,
],
'chart_2' => [
'legend_1' => 3,
'legend_2' => 2,
'legend_3' => 1,
'legend_4' => 0,
],
'chart_3' => [
'legend_1' => 6,
'legend_2' => 5,
'legend_3' => 4,
'legend_4' => 3,
'legend_5' => 2,
'legend_6' => 1,
'legend_7' => 0,
],
'chart_4' => [
'legend_1' => 4,
'legend_2' => 3,
'legend_3' => 2,
'legend_4' => 1,
'legend_5' => 0,
],
];
// Each bit of a bitmap is like a bucket, which stores the displayed or hidden state.
public const DEFAULT_CHART_LEGEND_VISIBILITIES = [
'chart_1' => 0b1111,
'chart_2' => 0b11111,
'chart_3' => 0b1111111,
'chart_4' => 0b11111100,
];

public function getChartLegendVisibilitiesAttribute(?string $value): array
{
$value = $value !== null ? \Safe\json_decode($value, true) : [];
$value += self::DEFAULT_CHART_LEGEND_VISIBILITIES;
$chart_legend_visibilities = [];

foreach ($value as $chart_name => $legend_visibilities_bitmap) {
foreach (self::BITMAP_INDEXES_BY_LEGEND_IDENTIFIER_BY_CHART_NAME[$chart_name] as $legend_identifier => $bitmap_index) {
$chart_legend_visibilities[$chart_name][$legend_identifier] = (bool) (($legend_visibilities_bitmap >> $bitmap_index) & 1);
}
}
ksort($chart_legend_visibilities);
return $chart_legend_visibilities;
}

public function setChartLegendVisibilitiesAttribute(?array $value): void
{
if ($value !== null) {
$chart_legend_visibilities = [];
foreach ($value as $chart_name => $legend_visibilities) {
$legend_visibilities_bitmap = 0;
foreach ($legend_visibilities as $legend_identifier => $legend_visibility) {
$bitmap_index = self::BITMAP_INDEXES_BY_LEGEND_IDENTIFIER_BY_CHART_NAME[$chart_name][$legend_identifier];
$legend_visibilities_bitmap |= ($legend_visibility & true) << $bitmap_index;
}
if ($legend_visibilities_bitmap !== self::DEFAULT_CHART_LEGEND_VISIBILITIES[$chart_name]) {
$chart_legend_visibilities[$chart_name] = $legend_visibilities_bitmap;
}
}
$value = $chart_legend_visibilities === [] ? null : \Safe\json_encode($chart_legend_visibilities);
}
$this->attributes[self::COLUMN_CHART_LEGEND_VISIBILITIES] = $value;
}

private static function getChartLegendVisibility(array $chart_data, UserExtra $user_extra, string $chart_name): array
{
$legend_label_id_by_store_index = array_flip(UserExtra::BITMAP_INDEXES_BY_LEGEND_IDENTIFIER_BY_CHART_NAME[$chart_name]);
$legend_visibilities = $user_extra->chart_legend_visibilities[$chart_name];
foreach ($chart_data['series'] as $series_index => $series) {
$key = array_shift($legend_label_id_by_store_index);
$chart_data['series'][$series_index]['id'] = $key;
$chart_data['series'][$series_index]['visible'] = $legend_visibilities[$key];
}
return $chart_data;
}