blocks|key|3773893|text|检查这两个答案的post，并注释它是您需要的。为了想出一个更清晰的解决方案，你翻转它们时想要调用的代码将它们放在Fragment类的public+method中，然后在ViewPager的onPageSelected中，通过position+(或者无论如何你想像ViewPager.getItem(pos)这样做)访问的特定片段将返回一个片段，你可以检查该片段是否是你喜欢的片段类的一个实例，并将其转换为你的代码并调用你的代码|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3773894|//suppose+i+have+my+fragment+via+myViewp.getItem(2)
if(fragmentObject+instanceof+MyFragmentClass){
++++//do+work
+}
+//put+else+and+check+for+others|code-block|syntax|javascript|3773895|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/31222735/how-to-load-the-fragment-activity-oncreate-method-of-the-actionbar-selected-ta^0|1K|8|1U|D|3N|M|8|4|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|F|3|G|5|H|7|12|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

check this <a href="https://stackoverflow.com/questions/31222735/how-to-load-the-fragment-activity-oncreate-method-of-the-actionbar-selected-ta">post</a> both answers and comment it is what you need. to also think of a clearer solution, the codes you want to call when you flip them put them in a <code>public method</code> in your <code>Fragment</code> class, then in your onPageSelected in your ViewPager the particular Fragment that is being accessed either by position (or anyway you want to do it like <code>ViewPager.getItem(pos)</code>) which will return a Fragment and you can check if that Fragment is an instanceof your preferred Fragment class and cast it to it and call your code

<pre><code>//suppose i have my fragment via myViewp.getItem(2)
if(fragmentObject instanceof MyFragmentClass){
 //do work
 }
 //put else and check for others
</code></pre>

blocks|key|5242253|text|没有对片段的直接回调；从框架来看，片段的所有三个生命周期都是相同的:它们附加到活动、创建、创建视图和恢复。这些回调都与它们在ViewPager中的显示方式无关，这是有充分理由的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5242254|相反，您感兴趣的是ViewPager中的回调。为此，您可以注册一个ViewPager.OnPageChangeListener|offset|length|5242255|@Override
public+void+onPageScrolled(int+position,+float+positionOffset,+int+positionOffsetPixels)+{
++++//+If+you+would+like+to+have+more+granular+control+than+onPageSelected(),
++++//+you+may+inspect+when+the+user+"begins+to+scroll"+to+the+next+page
}

@Override
public+void+onPageSelected(int+position)+{
++++Fragment+fragment+=+mAdapter.getItem(position);
++++if+(fragment+instanceof+OnMyFragmentSelectedListener)+{
++++++++((OnMyFragmentSelectedListener)+fragment).onMyFragmentSelected();
++++}
}

@Override
public+void+onPageScrollStateChanged(int+state)+{
}|code-block|syntax|javascript|5242256|在上面的代码片段中，我引入了一个名为OnMyFragmentSelectedListener的接口。如果您让片段实现它，并实现onMyFragmentSelected()方法，ViewPager将在其页面被选中时通知您的片段。|style|CODE|5242257|您可以通过使用OnPageChangeListener来做一些有趣的事情，例如，像在JazzyViewPager中那样在片段之间设置动画。在您的示例中，您可以在调用侦听器时开始加载附加数据。|5242258|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/reference/android/support/v4/view/ViewPager.OnPageChangeListener.html|1|https://github.com/jfeinstein10/JazzyViewPager^0|0|X|U|0|0|0|1R|M|0|16|E|1|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|11|8|@]|9|@$D|12|E|13|1|14]]|A|$]]|$1|F|3|G|5|H|7|15|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|16|8|@$D|17|E|18|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|19|8|@]|9|@$D|1A|E|1B|1|1C]]|A|$]]|$1|Q|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]|Y|$5|T|U|V|A|$W|Z]]]]

There's no immediate callback into the Fragment; from the framework, all three of the Fragment's lifecycles are identical: they are attached to the activity, created, create a view and resumed. None of those callbacks relate to how they appear within the ViewPager, and for good reason.

You are instead interested in the callbacks within the ViewPager. For this, you can register a <a href="http://developer.android.com/reference/android/support/v4/view/ViewPager.OnPageChangeListener.html" rel="nofollow">ViewPager.OnPageChangeListener</a>:

<pre><code>@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
 // If you would like to have more granular control than onPageSelected(),
 // you may inspect when the user "begins to scroll" to the next page
}

@Override
public void onPageSelected(int position) {
 Fragment fragment = mAdapter.getItem(position);
 if (fragment instanceof OnMyFragmentSelectedListener) {
 ((OnMyFragmentSelectedListener) fragment).onMyFragmentSelected();
 }
}

@Override
public void onPageScrollStateChanged(int state) {
}
</code></pre>

In the snippet above, I've introduced an interface called OnMyFragmentSelectedListener. If you have your fragments implement it, and implement the <code>onMyFragmentSelected()</code> method, the ViewPager will inform your fragment when its page has been selected.

You can do some fun things by using the OnPageChangeListener, for instance animating between fragments as in the <a href="https://github.com/jfeinstein10/JazzyViewPager" rel="nofollow">JazzyViewPager</a>. In your case, you can instead begin loading your additional data when the listener is called.

blocks|key|1325086|text|你需要通过setArguments传递你想要的数据。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1325087|+ChildFragment+fragment+=+new+ChildFragment();
+Bundle+bundle+=+new+Bundle();
+bundle.putInt("PARAMETER",+param);
+fragment+.setArguments(bundle);|code-block|syntax|javascript|1325088|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

you need to pass the data you want by setArguments.

<pre><code> ChildFragment fragment = new ChildFragment();
 Bundle bundle = new Bundle();
 bundle.putInt("PARAMETER", param);
 fragment .setArguments(bundle);
</code></pre>

blocks|key|1458585|text|检查此链接。它使用新的安卓架构和dagger+2在两个片段之间共享数据。https://github.com/MohitGoel9456/Android-Live-Data-Dagger2不需要使用参数和捆绑包来共享数据，因为这是旧的方式。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1458586|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/MohitGoel9456/Android-Live-Data-Dagger2^0|10|1M|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

Check this link. It is sharing data between two fragments using new android architecture and dagger 2. 
<a href="https://github.com/MohitGoel9456/Android-Live-Data-Dagger2" rel="nofollow noreferrer">https://github.com/MohitGoel9456/Android-Live-Data-Dagger2</a>
No need to share data using arguments and bundle as it is old way.

As answered below. The best approach is to add a listener to the viewpager to know when each fragment is selected.

This way the activity can trigger fragment refresh listener through an interface for example.

Fragment lifecycle Android

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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如下所示。最好的方法是向视图分页程序中添加一个侦听器，以了解每个片段何时被选中。这样，例如，活动可以通过接口触发片段刷新侦听器。

问片段生命周期Android
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