I found Kivy documentation, overall informative, vague in this particular area. It mentions three methods (sorry, dont have enough reputation to provide clicable links, relative paths to kivy.org provided, I'd be glad if someone could fix those links):

1. [存儲(chǔ)] ./docs/api-kivy.storage.html#module-kivy.storage
2. [設(shè)置] ./docs/api-kivy.uix.settings.html
3. [配置] ./docs/api-kivy.config.html

除此之外，我知道我可以通過(guò) pickle 或數(shù)據(jù)庫(kù)將數(shù)據(jù)存儲(chǔ)在文件中，但我想專門(mén)使用 sharedpreferences，或至少任何 Android/Kivy 特定的持久存儲(chǔ).

In addition to those, I'm aware that I could store data in a file, via pickle or database, but I'd like to use specifically sharedpreferences, or at least any Android/Kivy specific persistent storage.

1. 但是，我找不到任何比較或解釋它們有何不同以及如何使用它們.任何人都可以闡明一下，已經(jīng)使用過(guò)它們了嗎?

1. However, I was unable to find any comparison, or explanation how they are different, and how they are used. Could anyone shed some light, had used them already?

實(shí)際上，我有 80% 的把握這種方法都沒(méi)有使用 Android 的共享首選項(xiàng)，因此我考慮使用 jnius (4)，并且我嘗試過(guò)這樣做(方法 1,2/3?,4)，基于簡(jiǎn)單的 hello world 示例:

Actually, I'm 80% sure that neither of this method uses Android's shared preferences, thus I thought about using jnius (4), and to do that I've tried (methods 1,2/3?,4), based on simple hello world example:

from kivy.app import App
from kivy.uix.button import Button

import jnius  
from kivy.config import Config  
from kivy.storage.dictstore import DictStore  

class MyApp(App):

    def build(self):

        path = "DEFAULT"
        try:  
            path = Config.get('kivy', 'my_important_variable')  
            print "			 KIVY 1:", Config.get('kivy', 'my_important_variable')  
        except Exception as err:
            print ("KIVY, 1, error: {}".format(repr(err)))  

        try:
            store = DictStore("MY_SETTINGS")
            path = store.get("my_important_variable")
            print "			 KIVY 2:", path
        except KeyError as err:
            print ("KIVY, 2, error: {}".format(repr(err)))

        try:
            prefs_m = jnius.autoclass('android.preference.PreferenceManager')
            prefs = prefs_m.getSharedPreferences()
            path = prefs.getString("my_important_variable", None)
            print "			 KIVY 3:", path
        except jnius.jnius.JavaException as err:
            print ("KIVY, 3, error: {}".format(repr(err)))

        btn1 = Button(text=path)
        btn1.bind(on_press=app.callback) #
        return btn1

    def callback(self, instance):
        print('The button <%s> is being pressed, SAVING...' % instance.text)

        try:
            Config.set('kivy', 'my_important_variable', "my_value_1")
        except Exception as err:
            print ("KIVY, 4, error: {}".format(repr(err)))

        try:
            store = DictStore("MY_SETTINGS")
            store.put("MY_SETTINGS", my_important_variable="my_value_2")
        except Exception as err:
            print ("KIVY, 5, error: {}".format(repr(err)))

        try:
            prefs_c = jnius.autoclass('android.content.SharedPreferences')
            prefs_m = jnius.autoclass('android.preference.PreferenceManager')
            prefs = prefs_m.getSharedPreferences()
            prefs_e = prefs.Editor()
            prefs_e.putString("my_important_variable", "my_value_3")
            prefs_e.commit()
        except Exception as err:
            print ("KIVY, 6, error: {}".format(repr(err)))

        try:
            context = jnius.autoclass('android.content.Context')
            # do I actually get context or a class here?
            prefs = context.getPreferences(0).edit();
            prefs.putString("my_important_variable", "my_value_4")
            prefs.commit()
        except Exception as err:
            print ("KIVY, 7, error: {}".format(repr(err)))

if __name__ == '__main__':
    app = MyApp()
    app.run()

這是 logcat 的結(jié)果

and here are logcat's results

... each time app is launched 
I/python  ( 5973): KIVY, 1, error: No option 'my_important_variable' in section: 'kivy'
I/python  ( 5973): KIVY, 2, error: KeyError('my_important_variable',)
I/python  ( 5973): KIVY, 3, error: JavaException('Unable to find a None method!',)

... button pressed
I/python  ( 5973): The button <DEFAULT> is being pressed, SAVING...
I/python  ( 5973): KIVY, 6, error: JavaException('Unable to find a None method!',)
I/python  ( 5973): KIVY, 7, error: AttributeError("type object 'android.content.Context' has no attribute 'getPreferences'",)

請(qǐng)注意，沒(méi)有調(diào)用 4、5 個(gè)錯(cuò)誤消息"，所以理論上它們應(yīng)該可以工作，但是第二次啟動(dòng)我得到了同樣的錯(cuò)誤.我已經(jīng)沒(méi)有辦法破解它了.

Notice, that 4, 5 "error msg's" didn't get called, so in theory they should have worked, but second launch I get same errors. I've run out of ideas how to crack it.

推薦答案

Kivy.Config 用于存儲(chǔ)與 App 類的實(shí)例化相關(guān)的設(shè)置.它通常在導(dǎo)入任何其他 kivy 模塊之前放置在 Python 腳本的最頂部.此方法不是特定于平臺(tái)的，但配置文件的默認(rèn)路徑會(huì)根據(jù)平臺(tái)而變化.

Kivy.Config is used to store settings that relate to the instantiation of the App class. It is usually placed at the very top of your Python script before any other kivy module is imported. This method is not platform specific, but the default path to the config file changes depending on the platform.

from kivy.config import Config
desktop=Config.getint('kivy', 'desktop')
if desktop == 1:
    print "This app is being run on a desktop."

DictStore 是一個(gè)將字典存儲(chǔ)到磁盤(pán)的存儲(chǔ)類.filename 參數(shù)指定存儲(chǔ)字典的文件的名稱.調(diào)用 get 函數(shù)時(shí)，會(huì)返回一個(gè) Python 字典.

The DictStore is a storage class that stores a dictionary to disk. The filename argument specifies the name of the file where the dictionary is stored. When the get function is called, a Python dictionary is returned.

from kivy.app import App
from kivy.uix.button import Button
from kivy.storage.dictstore import DictStore

class TestApp(App):
    def build(self):
        try:
            store = DictStore(filename="MY_SETTINGS")
            dictionary = store.get("my_important_variable")
            print "			 KIVY 2: DictStore Succeeded",
        except KeyError as err:
            dictionary = {'name': 'None'}
            print ("KIVY, 2, error: {}".format(repr(err)))

        self.text = str(dictionary)
        btn1 = Button(text=self.text)
        btn1.bind(on_press=self.callback) #
        return btn1

    def callback(self, instance):
        print('The button <%s> is being pressed, SAVING...' % instance.text)
        try:
            store = DictStore(filename="MY_SETTINGS")
            store.put("my_important_variable", name="John")
        except Exception as err:
            print ("KIVY, 5, error: {}".format(repr(err)))



if __name__ == '__main__':
    TestApp().run()

我將在下面提供訪問(wèn)共享首選項(xiàng)的代碼.如果您有興趣了解更多信息，請(qǐng)閱讀 http://developer.android.com/guide/topics/data/data-storage.html 和 https://kivy.org/planet/2015/04/python-on%C2%A0android/

I will provide the code for accessing shared prefs below. If you are interested in learning more please read http://developer.android.com/guide/topics/data/data-storage.html and https://kivy.org/planet/2015/04/python-on%C2%A0android/

from kivy.app import App
from kivy.uix.button import Button

import jnius

class TestApp(App):
    def build(self):
        try:
            PythonActivity = jnius.autoclass('org.renpy.android.PythonActivity')
            activity = PythonActivity.mActivity
            cntxt = activity.getApplicationContext()
            prefs = cntxt.getSharedPreferences("MY_PREFS", cntxt.MODE_PRIVATE )
            print "KIVY ACQUIRED SHARED PREFS"
            myVar = prefs.getString("my_important_variable", "Default String")
            print "	KIVY 3: Retrieved SharedPref"
        except jnius.jnius.JavaException as err:
            myVar="Error Loading Prefs."
            print ("KIVY, 3, error: {}".format(repr(err)))

        self.text = myVar
        btn1 = Button(text=self.text)
        btn1.bind(on_press=self.callback) #
        return btn1

    def callback(self, instance):
        print('The button <%s> is being pressed, SAVING...' % instance.text)
        try:
            PythonActivity = jnius.autoclass('org.renpy.android.PythonActivity')
            activity = PythonActivity.mActivity
            cntxt = activity.getApplicationContext()
            prefs = cntxt.getSharedPreferences("MY_PREFS", cntxt.MODE_PRIVATE)
            editor = prefs.edit()
            editor.putString("my_important_variable", "This is important!")
            editor.commit()
            print "	KIVY: Added string <This is important!> to shared prefs."
        except Exception as err:
            print ("	KIVY, 6, error: {}".format(repr(err)))

if __name__ == '__main__':
    TestApp().run()

這篇關(guān)于Kivy 和 android 共享首選項(xiàng)的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！