Question

如果更改通知者的类型为bool，我可以这样更改文本：

import pandas as pd
from bokeh.plotting import figure
from bokeh.io import output_file, show, curdoc
from bokeh.layouts import gridplot, widgetbox, row, column
from bokeh.models import HoverTool, ColumnDataSource,CategoricalColorMapper, Slider, CustomJS, CheckboxButtonGroup, Select, CheckboxGroup, RadioGroup, Toggle, Button, Dropdown

df1 = pd.read_csv('C:/PStuff/dataA.txt')

p1 = figure(plot_width=600, plot_height=300)
source1 = ColumnDataSource(data={'x':df1['num'],'y1':df1['col1'], 'y2':df1[new]}) 
p1.multi_line(x = 'x', ys = ['y1', 'y2'], source=source1)
menu1 = Select(options=['col1', 'col2', 'col3', 'col4'], value='col1', title='Welds')

def callback1(attr, old, new):
   source1.data.update({'y':df1[new]})
menu1.on_change('value', callback1)

# show(row(p1, menu1))
layout = column(menu1, p1)
curdoc().add_root(layout)

LoginorSignup.dart：

...
Consumer<LoginOrSignup>(
  builder: (context, value, child) =>
      Text(value.isSignup? "Sign up" : "Login")
)
...

如果 _isSignup 类型为int，如何更改文本？

Answer 1

是的，应该将方法添加到 LoginOrSignup 类中，然后在需要时调用此方法，如下所示：

import 'package:flutter/foundation.dart';

class LoginOrSignup extends ChangeNotifier{
  bool _isSignup = false;

  bool get isSignup => _isSignup;

  void changeStatus(bool status){
    _isSignup = status;
    notifyListeners();
  }
}

在您的视像通话中

value.changeStatus(false); //or true

Flutter＆provider：如何通过提供者的int值更改文本？

1 个答案: