我在调用onDestroyedView（）时切换片段，将保留成员变量，并且当调用onDestroy（）时，我可以从bundle中恢复它们，因为在onDestroy（）之前调用onSaveInstanceState。但是现在我遇到了一个问题成员变量重置为初始值，我查了很多文档，但我不知道为什么会发生这种情况？
答案 0 :(得分：1)
onSaveInstanceState是否总是将我的成员变量保存在Fragment中？
没有。 Bundle保存您作为参数传入的Bundle中的任何内容。然后，您可以从onCreate()或其他片段生命周期方法中的#Adapted from https://djangosnippets.org/snippets/2619/
@register.tag(name='counter')
def do_counter(parser, token):
"""
Counter tag. Can be used to output and increment a counter.
Usage:
- {% counter %} to output and post-increment the counter variable
- {% counter reset %} to reset the counter variable to 1
- {% counter last %} to access the last counter variable without incrementing
"""
try:
tag_name, request = token.contents.split(None, 1)
except ValueError:
request = None
if request == 'reset':
reset = True
last = False
elif request == 'last':
last = True
reset = False
else:
reset = False
last = False
return CounterNode(reset, last)
class CounterNode(template.Node):
def __init__(self, reset, last):
self.reset = reset
self.last= last
def render(self, context):
# When initializing or resetting, set counter variable in render_context to 1.
if self.reset or ('counter' not in context.render_context):
context.render_context['counter'] = 1
# When resetting, we don't want to return anything
if self.reset:
return ''
# When ask for last, return previous count
if self.last:
return context.render_context['counter']-1
counter = context.render_context['counter']
# Increment counter
context.render_context['counter'] += 1
# Return counter number
return counter
中获取值。