将ViewPager中的片段设置为当前页面时的回调 [英] Callbacks for when a Fragment in a ViewPager is set as current page

问题描述

我有一个viewpager，它有5个片段页面.我可以通过点击导航按钮在每个片段之间进行切换.

I have a viewpager, it has 5 fragments page. I can switch between each fragment by tapping a navigation button.

现在，我要实现的是进入页面时刷新页面1.(例如，我在第1页中，当我点击第2页的按钮时，第2页将显示并刷新.

Now, what I'm trying to achieve is to refresh 1 of the page when entering it. (e.g. I'm in Page 1, when I tap button for Page 2, Page 2 will display and refresh.

但是，我发现此行为未调用片段中的onResume方法.或其他任何生命周期方法.

However, I find out that the onResume method in the fragment is not called on this behavior. or any of the other lifecycle method.

我似乎找不到办法.在这种情况下我可以使用任何回调吗?

I can't seem to find a way to do this. Is there any callbacks I can use for such scenario?

推荐答案

由于不需要任何缓存，因此使用 viewPager.setOffscreenPageLimit(0)，这样就不会在后台加载页面，并且仅在实际显示页面时才会调用 onResume . UPD::谢谢，Yarh，指出了 setOffscreenPageLimit(0)不起作用.抱歉.

Since you don't need any kind of caching, it's probably a good idea for you to use viewPager.setOffscreenPageLimit(0) so pages won't be loaded in background, and onResume will be called only when page is actually displayed. UPD: Thanks, Yarh, for pointing out that setOffscreenPageLimit(0) doesn't work. Sorry for that.

如果这不适用于您，请使用 viewPager.addOnPageChangeListener(listener)- onPageSelected(position)方法应该有帮助.

If this doesn't work for you, use viewPager.addOnPageChangeListener(listener) - onPageSelected(position) method should help.

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