如何在Plotly Dash上获取动画滑块的当前值？

在Plotly Dash上获取动画滑块的当前值可以通过回调函数实现。以下是一个简单的示例代码，展示了如何实现这一功能：

import dash
from dash import dcc, html
from dash.dependencies import Input, Output
import plotly.graph_objs as go

app = dash.Dash(__name__)

app.layout = html.Div([
    dcc.Graph(id='graph-with-slider'),
    dcc.Slider(
        id='year-slider',
        min=1950,
        max=2020,
        value=1950,
        step=1,
        marks={str(year): str(year) for year in range(1950, 2021, 10)}
    ),
    html.Div(id='slider-output')
])

@app.callback(
    Output('slider-output', 'children'),
    [Input('year-slider', 'value')]
)
def display_value(value):
    return f'当前年份: {value}'

@app.callback(
    Output('graph-with-slider', 'figure'),
    [Input('year-slider', 'value')]
)
def update_figure(selected_year):
    # 这里可以根据选中的年份更新图表数据
    # 示例数据
    data = [
        go.Scatter(
            x=[1, 2, 3],
            y=[4, 5, 6],
            mode='markers',
            marker=dict(color='blue')
        )
    ]
    layout = go.Layout(
        title=f'年份 {selected_year} 的数据',
        xaxis=dict(title='X轴'),
        yaxis=dict(title='Y轴')
    )
    return go.Figure(data=data, layout=layout)

if __name__ == '__main__':
    app.run_server(debug=True)