How to update the echarts plot theme dynamicaly - echarts

Question

Can someone explain to me how to toggle from light to dark theme without reloading the page??
I have this code that checks if the theme is light or dark and I want to change the theme dynamically base on the theme.
my code so far
initECharts(days: any, hours: any, data: any) {
if (this._chart) {
this._chart.clear();
this._chart = null;
}
// console.log('days: ', this.days);
// console.log('hours: ', this.hours);
// console.log('values: ', this.values);
data = this.reconstructData(days, hours, data);
// const x: any = document.getElementById('main');
const theme = (this._themeService.theme === 'dark') ? 'dark' : 'light';
console.log('theme', theme);
const domEl: any = this.main.nativeElement;
this._chart = echarts.init(domEl, theme);
// specify chart configuration item and data
const option: any = {
tooltip: {
position: 'top'
},
animation: false,
grid: {
height: '50%',
y: '10%'
},
xAxis: {
type: 'category',
data: hours,
splitArea: {
show: true
},
nameTextStyle: {
color: 'red'
}
},
yAxis: {
type: 'category',
data: days,
splitArea: {
show: true
}
},
visualMap: {
min: 0,
max: 10,
calculable: true,
orient: 'horizontal',
left: 'center',
bottom: '15%'
},
series: [{
name: 'Punch Card',
type: 'heatmap',
data: data,
label: {
normal: {
show: true
}
},
itemStyle: {
emphasis: {
shadowBlur: 10,
shadowColor: 'rgba(0, 0, 0, 0.5)'
}
}
}]
};
// use configuration item and data specified to show chart
this._chart.setOption(option);
}

Answer 1

Ok, I found it.
every time you want to update the theme dynamically example a button or an observable or Promise, you must call this method
echarts.dispose(this._chart);
then you call the initMethod, example:
this.initECharts();
The init method can look like this in my case.
initECharts(days: any, hours: any, data: any) {
data = this.reconstructData(days, hours, data);
// const x: any = document.getElementById('main');
const theme = (this._themeService.theme === 'dark') ? 'dark' : 'light';
console.log('theme', theme);
const domEl: any = this.main.nativeElement;
this._chart = echarts.init(domEl, theme);
// specify chart configuration item and data
const option: any = {
tooltip: {
position: 'top'
},
animation: false,
grid: {
height: '50%',
y: '10%'
},
xAxis: {
type: 'category',
data: hours,
splitArea: {
show: true
},
nameTextStyle: {
color: 'red'
}
},
yAxis: {
type: 'category',
data: days,
splitArea: {
show: true
}
},
visualMap: {
min: 0,
max: 10,
calculable: true,
orient: 'horizontal',
left: 'center',
bottom: '15%'
},
series: [{
name: 'Punch Card',
type: 'heatmap',
data: data,
label: {
normal: {
show: true
}
},
itemStyle: {
emphasis: {
shadowBlur: 10,
shadowColor: 'rgba(0, 0, 0, 0.5)'
}
}
}]
};
// use configuration item and data specified to show chart
this._chart.setOption(option);
}