参考自：Multiple-Outputs-in-Dash-Now-Available
Features（特性）
- Use a list/tuple of Output as output in callbacks.
- Return a tuple/list of value from the callbacks
- The returned list must have the same length as the list of output （返回和声明Output的个数应该相同）
- The output props are applied in the order they were declared in the output list（应该按照声明顺序返回）
代码：
import dash
import dash_core_components as dcc
import dash_table as dt
import dash_html_components as htmlfrom dash.dependencies import Output, Input
from dash.exceptions import PreventUpdateimport plotly.graph_objs as gosample_data = {'series': {'data': [{'title': 'Game of Thrones', 'score': 9.5},{'title': 'Stranger Things', 'score': 8.9},{'title': 'Vikings', 'score': 8.6}],'style': {'backgroundColor': '#ff998a'}},'movies': {'data': [{'title': 'Rambo', 'score': 7.7},{'title': 'The Terminator', 'score': 8.0},{'title': 'Alien', 'score': 8.5}],'style': {'backgroundColor': '#fff289'}}
}app = dash.Dash(__name__)app.layout = html.Div([html.H1('Multi output example'),dcc.Dropdown(id='data-dropdown', options=[{'label': 'Movies', 'value': 'movies'},{'label': 'Series', 'value': 'series'}], value='movies'),html.Div([dcc.Graph(id='graph'),dt.DataTable(id='data-table', columns=[{'name': 'Title', 'id': 'title'},{'name': 'Score', 'id': 'score'}])])
], id='container')#在此声明output
@app.callback([Output('graph', 'figure'),Output('data-table', 'data'),Output('data-table', 'columns'),Output('container', 'style')
], [Input('data-dropdown', 'value')])
def multi_output(value):if value is None:raise PreventUpdateselected = sample_data[value]data = selected['data']columns = [{'name': k.capitalize(), 'id': k}for k in data[0].keys()]figure = go.Figure(data=[go.Bar(x=[x['score']], text=x['title'], name=x['title'])for x in data])#在此返回outputreturn figure, data, columns, selected['style']if __name__ == '__main__':app.run_server(debug=True, port=8056)效果：
更改了图、数据及其样式
在此之前，大家都是通过def 多个function来实现对多个Output的操作。
除此之外，官方文档里还有一个案例，但是我没怎么看懂，附上地址https://dash.plot.ly/state，最下面。
说是return dash.no_update, '{} is prime!'.format(num)，dash.no_update
- # dash.no_update prevents any single output updating
- # (note: it's OK to use for a single-output callback too)