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Java 如何在FragmentActivity中强制转换应用程序类_Java_Android_Android Fragments - Fatal编程技术网

Java 如何在FragmentActivity中强制转换应用程序类

Java 如何在FragmentActivity中强制转换应用程序类,java,android,android-fragments,Java,Android,Android Fragments,我想在我的MapsActivity(扩展到FragmentActivity)中强制转换扩展到应用程序的类。我尝试getActivity().getApplication(),但它有错误无法解析方法“getActivity()”,当我尝试getApplication()时,它只抛出运行时错误java.lang.ClassCastException。我怎样才能修好它?你可以试试这个 ApplicationClassName appCtx = (ApplicationClassName ) getAc

我想在我的MapsActivity(扩展到FragmentActivity)中强制转换扩展到应用程序的类。我尝试
getActivity().getApplication()
,但它有错误无法解析方法“getActivity()”,当我尝试
getApplication()
时,它只抛出运行时错误java.lang.ClassCastException。我怎样才能修好它?

你可以试试这个

ApplicationClassName appCtx = (ApplicationClassName ) getActivity().getApplication();

我已经试过了。但它无法解析方法getActivity(),因为它抛出运行时错误java.lang.ClassCastException
MyApplication myApp = (MyApplication) getApplication();