N_intervals value shows differently in callback

Dash Python
1

Hi, I have this short code that use the dcc.Interval component to update a text in the callback, where I tried to print out the value of the n_intervals property.

from dash import Dash, html, dcc, Input, Output

app = Dash()

dccinterval = dcc.Interval(
    id='interval-component',
    interval=1000,
    n_intervals=0
)

app.layout = html.Div(
    children=[
        html.Div(id='live-update-text'),
        dccinterval
    ]
)


@app.callback(Output('live-update-text', 'children'),
              Input(dccinterval, 'n_intervals'))
def update_message(n):
    print('current interval in update_message: ', dccinterval.n_intervals)
    print('current n in update_message: ', n)
    return 'Message: ' + str(n)


if __name__ == '__main__':
    app.run_server(debug=True, port=8058)

Here is the output:

current interval in update_message:  0
current n in update_message:  0
current interval in update_message:  0
current n in update_message:  1
current interval in update_message:  0
current n in update_message:  2
current interval in update_message:  0
current n in update_message:  3
.
.
.

As you might see that the value of n_intervals got via the Input is changing correctly, but the value got directly from the interval component always stays at 0. I am wondering why. Can someone please help me with this? The reason I need to figure this out is that in my application when I tried to change the n_intervals’ value via component fails. That is, when I tried to set the value by doing dccinterval.n_intervals = a number, it didn’t not work.

Thank you very much for any comments!