带有回调的kivy Urlrequest在移动设备上引发错误，但在笔记本电脑上却没有，为什么？

如何解决带有回调的kivy Urlrequest在移动设备上引发错误，但在笔记本电脑上却没有，为什么？

下面是完整的代码。

当我在笔记本电脑上运行以下简单的kivy代码时，输​​出为“来自Kivy Success的Hello”。当我使用buildozer android debug deploy运行时，从ubuntu到我的手机运行的输出是“ Hello from Kivy Error”。我什至在我的项目文件夹中添加了cacert.pem，使用了ca_file = where（），verify = True。那也没有帮助。

为什么UrlRequest在我的手机上失败？请帮我解决。

from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.network.urlrequest import UrlRequest
from kivy.uix.label import Label
from kivy.uix.button import Button
import json

def where():
    f = os.path.dirname(__file__)

    return os.path.join(f,'cacert.pem')   


class MainScreen(FloatLayout):
    def __init__(self,**kwargs):
        super(MainScreen,self).__init__(**kwargs)
        self.a = None            
        self.test_connection()
        print(" I am in init")

    def on_getCloudEvents_success(self,request,result):
        print("on_getCloudEvents_success called:")
        print("  result="+str(result))
        self.resp = result
        self.SYNC_REQUEST_STAT="Success" # to end the synchronous wait
        self.after_success()
        
        
    def on_getCloudEvents_failure(self,result):
        print("on_getCloudEvents_failure called:")
        print("  request was sent to "+str(request.url))
        print("    request body="+str(request.req_body))
        print("    request headers="+str(request.req_headers))
        print("  result="+str(request.result))
        self.SYNC_REQUEST_STAT="Failure" # to end the synchronous wait
        self.after_success()

    def on_getCloudEvents_error(self,result):
        print("on_getCloudEvents_error called:")
        print("  request was sent to "+str(request.url))
        print("    request body="+str(request.req_body))
        print("    request headers="+str(request.req_headers))
        print("  result="+str(request.result))        
        self.SYNC_REQUEST_STAT="Error" # to end the synchronous wait
        self.after_success()
            
      
    def after_success(self):
#        button = Button(text='Hello world'+self.a)
#        self.add_widget(button)
        self.a = "heree"
        label = Label(text='Hello from Kivy'+self.SYNC_REQUEST_STAT,size_hint=(.5,.5),pos_hint={'center_x': .5,'center_y': .5},color = [1.4,1,1.8])
    
        self.add_widget(label)
        return self

        
    def test_connection(self):
        
        jdata = {"symbols": {"tickers": ["BITTREX:BTCUSDT"],"query": {"types": []}},"columns": ["Recommend.Other|15","Recommend.All|15","Recommend.MA|15","RSI|15","RSI[1]|15","Stoch.K|15","Stoch.D|15","Stoch.K[1]|15","Stoch.D[1]|15","CCI20|15","CCI20[1]|15","ADX|15","ADX+DI|15","ADX-DI|15","ADX+DI[1]|15","ADX-DI[1]|15","AO|15","AO[1]|15","Mom|15","Mom[1]|15","MACD.macd|15","MACD.signal|15","Rec.Stoch.RSI|15","Stoch.RSI.K|15","Rec.WR|15","W.R|15","Rec.BBPower|15","BBPower|15","Rec.UO|15","UO|15","close|15","EMA5|15","SMA5|15","EMA10|15","SMA10|15","EMA20|15","SMA20|15","EMA30|15","SMA30|15","EMA50|15","SMA50|15","EMA100|15","SMA100|15","EMA200|15","SMA200|15","Rec.Ichimoku|15","Ichimoku.BLine|15","Rec.VWMA|15","VWMA|15","Rec.HullMA9|15","HullMA9|15","Pivot.M.Classic.S3|15","Pivot.M.Classic.S2|15","Pivot.M.Classic.S1|15","Pivot.M.Classic.Middle|15","Pivot.M.Classic.R1|15","Pivot.M.Classic.R2|15","Pivot.M.Classic.R3|15","Pivot.M.Fibonacci.S3|15","Pivot.M.Fibonacci.S2|15","Pivot.M.Fibonacci.S1|15","Pivot.M.Fibonacci.Middle|15","Pivot.M.Fibonacci.R1|15","Pivot.M.Fibonacci.R2|15","Pivot.M.Fibonacci.R3|15","Pivot.M.Camarilla.S3|15","Pivot.M.Camarilla.S2|15","Pivot.M.Camarilla.S1|15","Pivot.M.Camarilla.Middle|15","Pivot.M.Camarilla.R1|15","Pivot.M.Camarilla.R2|15","Pivot.M.Camarilla.R3|15","Pivot.M.Woodie.S3|15","Pivot.M.Woodie.S2|15","Pivot.M.Woodie.S1|15","Pivot.M.Woodie.Middle|15","Pivot.M.Woodie.R1|15","Pivot.M.Woodie.R2|15","Pivot.M.Woodie.R3|15","Pivot.M.Demark.S1|15","Pivot.M.Demark.Middle|15","Pivot.M.Demark.R1|15"]}
        jdata = json.dumps(jdata).encode('utf-8')    
        print(jdata)
        scan_url = 'https://scanner.tradingview.com/crypto/scan'
        UrlRequest(scan_url,req_body=jdata,on_success=self.on_getCloudEvents_success,on_failure=self.on_getCloudEvents_failure,on_error=self.on_getCloudEvents_error)

class App(App):   
        
    def build(self):
        return MainScreen()
        

if __name__ == "__main__":
    App().run()

解决方法

我解决了我的问题。在buildozer规格要求中，我必须添加python3 == 3.7.5，hostpython3 == 3.7.5。