问题

I am trying to recreate this Plotly example with Dash, but I cannot get the buttons and the range slider. Does anyone know how I can do this?

That's what I tried:

traces =[{
            'x':df.index,
            'y':df.level,
            'type': 'scatter',
            'mode': 'lines',
            'name': 'a_level'
    }]
    graphs.append(dcc.Graph(
        id='a_level',
        figure={
            'data': traces,
            'layout': {
                    'type': 'date',
                    'rangeslider': {'visible':True},
                    'margin': {'b': 0, 'r': 10, 'l': 60, 't': 0}
            }
        }
    )

回答1:

The RangeSlider is a Dash Core Component, it's not an attribute of Graph (which is also a Dash Core Component).

Here is a simple app layout:

import dash_core_components as dcc

app.layout = html.Div(children=[
    html.H1('My Dash App'),
    html.Div(
        [
            html.Label('From 2007 to 2017', id='time-range-label'),
            dcc.RangeSlider(
                id='year_slider',
                min=1991,
                max=2017,
                value=[2007, 2017]
            ),
        ],
        style={'margin-top': '20'}
    ), 
    html.Hr(),
    dcc.Graph(id='my-graph')
])

Now you just have to define a callback that gets called every time the value of the RangeSlider changes. This is the Input that causes _update_graph to get called. You could have multiple inputs (e.g. a Dropdown, another RangeSlider, etc).

The Output is always a single one. In this example it's the figure attribute of the Graph component.

# the value of RangeSlider causes Graph to update
@app.callback(
    output=Output('my-graph', 'figure'),
    inputs=[Input('year_slider', 'value')]
    )
def _update_graph(year_range):
    date_start = '{}-01-01'.format(year_range[0])
    date_end = '{}-12-31'.format(year_range[1])
    # etc...

A Dash Core Component could cause several components to update. For example, a RangeSlider could cause a Label to change.

# the value of RangeSlider causes Label to update
@app.callback(
    output=Output('time-range-label', 'children'),
    inputs=[Input('year_slider', 'value')]
    )
def _update_time_range_label(year_range):
    return 'From {} to {}'.format(year_range[0], year_range[1])

回答2:

rangeslider is a property of xaxis.

I use something like this:

app = dash.Dash(__name__, external_stylesheets=['https://codepen.io/chriddyp/pen/bWLwgP.css'])
    app.layout = html.Div([
        dcc.Graph(
            id='bar_plot',
            figure=go.Figure(
                data=area,
                layout=go.Layout(
                    xaxis={
                        'rangeslider': {'visible':True},
                        'rangeselector': {'visible':True, 'buttons':[{'step':'all'}, {'step':'day'}, {'step':'hour'}]}
                    },
                )))
    ])

回答3:

I did something like this (with a df that has datetimeindex):

Function

def get__marks(f):

dates = {}
for z in f.index:
    dates[f.index.get_loc(z)] = {}
    dates[f.index.get_loc(z)] = str(z.month) + "-" + str(z.day)

return j

App Layout

dcc.RangeSlider(
    id='range-slider',
    updatemode='mouseup',
    min=0,
    max=len(df.index) - 1,
    count=1,
    step=1,
    value=[0, len(df.index) - 1],
    marks=get_marks(df),
)

来源：https://stackoverflow.com/questions/46519518/how-to-range-slider-and-selector-with-plotly-dash

标签

python