Unable to instantiate fragment make sure class name....

最新推荐文章于 2022-05-03 20:20:06 发布
原创 最新推荐文章于 2022-05-03 20:20:06 发布 · 1.2k 阅读 · 0 ·
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本文探讨了在使用Viewpager+Fragment时，遇到的无法启动Activity的异常问题，具体为RuntimeException和Fragment$InstantiationException。通过分析发现，自定义Fragment仅定义了带参数的构造方法时，需要确保添加参数为空的构造函数。本文提供了解决方法并解释了其背后的原因。

最近使用Viewpager + Fragment来做应用，经常会遇到如下错误

E/UncaughtException-main(13661): java.lang.RuntimeException: Unable to start activity ComponentInfo{......}: android.app.Fragment$InstantiationException: Unable to instantiate fragment xxxxxx...: make sure class name exists, is public, and has an empty constructor that is public

解决办法：

自定义的fragment 如果只定义了带参数的构造方法，那么要把参数为空的构造函数一并写上。原因待进一步研究，知道的朋友不吝赐教！




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