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This class allows interaction with an emulator's battery.  Tests running on an emulator will have an instance of this class available as self.marionette.emulator.battery.



Attribute Type Description
charging bool Sets or returns the charging state of the emulator's battery.
level float Sets or returns the battery level, from 0.0 to 1.0.


This example sets the battery level to 25%. This example uses the execute_script call, which is used to execute arbitrary JavaScript in either the chrome or content process of a window. By default, as shown here, it gets executed in the content window.

from marionette_test import *

class TestBatteryLevel(MarionetteTestCase):

    def test_level(self):
        # make sure we're really running on an emulator
        # set the current battery level to 25%
        self.marionette.emulator.battery.level = 0.25
        # read the battery level and make sure it's the same
        self.assertEqual(25, int(self.marionette.emulator.battery.level * 100), "unexpected battery level")
        # check it against the battery WebAPI by executing and returning the webAPI call in the window
        moz_level = self.marionette.execute_script("return navigator.mozBattery.level;")
        self.assertEqual(25, int(moz_level * 100), "unexpected mozBattery level")

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 Contributors to this page: fscholz, Sheppy, jgriffin, mdas
 Last updated by: fscholz,