小编Can*_*mas的帖子

您可能知道Android支持嵌套片段,也可以通过API级别为17的支持库.所以基本上我正在尝试将嵌套片段添加到ViewPager的一个片段中,并熟悉这个新的好功能.

在第一次应用程序启动时,一切都按预期工作,即我可以添加子片段,浏览这些片段,处理后栈等.

但问题是当我通过单击"返回"按钮离开应用程序并重新启动应用程序时,我在大多数情况下得到以下异常,并非总是如此:

java.lang.IllegalStateException: Activity has been destroyed
    at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1342)
    at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
    at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574)
    at com.cnlms.andnestedfragments.ui.fragments.FragWrapper.addChildFragment(FragWrapper.java:145)
    at com.cnlms.andnestedfragments.ui.fragments.FragWrapper.onActivityCreated(FragWrapper.java:96)
    at android.support.v4.app.Fragment.performActivityCreated(Fragment.java:1468)
    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:931)
    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
    at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
    at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
    at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
    at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
    at android.support.v4.view.ViewPager.populate(ViewPager.java:1012)
    at android.support.v4.view.ViewPager.populate(ViewPager.java:881)
    at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1366)
    at android.view.View.measure(View.java:15172)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814)
    at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
    at android.view.View.measure(View.java:15172)
    at android.widget.LinearLayout.measureVertical(LinearLayout.java:833)
    at android.widget.LinearLayout.onMeasure(LinearLayout.java:574)
    at android.view.View.measure(View.java:15172)
    at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814)
    at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
    at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2148)
    at android.view.View.measure(View.java:15172)
    at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1848)
    at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1100)
    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1273)
    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:998)
    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4212)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725)
    at android.view.Choreographer.doCallbacks(Choreographer.java:555)
    at android.view.Choreographer.doFrame(Choreographer.java:525)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:711)
    at android.os.Handler.handleCallback(Handler.java:615) …

我想要完成的是将一些常见的任务和功能分组到一个 common.gradle 文件下，并通过简单地调用主 build.gradle 来在不同的项目中重用这些任务和方法：

apply from: 'common.gradle'

我在 common.gradle 文件中有以下方法：

def readPackageNameFromManifest() {
    def manifestParser = new com.android.builder.DefaultManifestParser()
    return manifestParser.getPackage(android.sourceSets.main.manifest.srcFile) 
}

但它一直告诉我：

> Could not compile script 'common.gradle'
 unable to resolve class com.android.builder.DefaultManifestParser 
   @ line 77, column 26.
         def manifestParser = new com.android.builder.DefaultManifestParser()  

当我在 build.gradle 下移动方法时，它不会引起任何问题。

我可能漏掉了一点。我会很感激你的想法。谢谢！