Question

我正在寻找一种从Kivy框架中持久存储Android设备上的设置的方法。

我在这一特定领域发现了Kivy文档，整体信息丰富，模糊不清。它提到了三种方法（抱歉，没有足够的声誉提供可引用的链接，提供 kivy.org 的相对路径，如果有人可以修复这些链接，我会很高兴 的）：

[存储] ./docs/api-kivy.storage.html#module-kivy.storage
[设置] ./docs/api-kivy.uix.settings.html
[Config] ./docs/api-kivy.config.html

除此之外，我知道我可以通过pickle或数据库将数据存储在文件中，但我想特别使用sharedpreferences，或者至少使用任何Android / Kivy特定的持久存储

但是，我无法找到任何比较或解释它们是如何不同的，以及如何使用它们。任何人都可以使用它们吗？

实际上，我80％确定这种方法都没有使用Android的共享首选项，因此我考虑使用jnius（4），为此我尝试过（方法1,2 / 3？，4），基于简单的hello world示例：

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 "\t\t\t 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 "\t\t\t 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 "\t\t\t 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()

这里是logcat的结果

... 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'",)

请注意，4,5“错误信息”没有被调用，所以理论上他们应该有效，但第二次启动我得到相同的错误。我已经没有想法如何破解它。

Answer 1

Kivy.Config用于存储与App类实例化相关的设置。在导入任何其他kivy模块之前，它通常位于Python脚本的最顶层。此方法不是特定于平台的，但配置文件的默认路径会根据平台而变化。

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

DictStore是一个将字典存储到磁盘的存储类。 filename参数指定存储字典的文件的名称。调用get函数时，将返回Python字典。

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 "\t\t\t 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()

我将在下面提供访问共享首选项的代码。如果您有兴趣了解更多信息，请参阅http://developer.android.com/guide/topics/data/data-storage.html和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 "\tKIVY 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 "\tKIVY: Added string <This is important!> to shared prefs."
        except Exception as err:
            print ("\tKIVY, 6, error: {}".format(repr(err)))

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

Kivy和android共享偏好

1 个答案: