Question

我试图在android studio中编写登录/注册程序，我在youtube上关注了本教程：https://www.youtube.com/watch?v=3RewvdB82PY 但我的应用程序一直在崩溃。

我的logcat看起来像这样：

   04-29 00:01:58.833 10970-10970/com.myproject.az.myapp E/AndroidRuntime: FATAL EXCEPTION: main

Process: com.myproject.az.myapp, PID: 10970
                                                                         java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myiscaeproject.az.myapp/com.myiscaeproject.az.myapp.activities.MainLogIn}: java.lang.ClassCastException: android.support.design.widget.TextInputEditText cannot be cast to android.support.design.widget.TextInputLayout
                                                                             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
                                                                             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
                                                                             at android.app.ActivityThread.-wrap12(ActivityThread.java)
                                                                             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
                                                                             at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                             at android.os.Looper.loop(Looper.java:154)
                                                                             at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                                             at java.lang.reflect.Method.invoke(Native Method)
                                                                             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                                             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
                                                                          Caused by: java.lang.ClassCastException: android.support.design.widget.TextInputEditText cannot be cast to android.support.design.widget.TextInputLayout
                                                                             at com.myiscaeproject.az.myapp.activities.MainLogIn.initViews(MainLogIn.java:54)
                                                                             at com.myiscaeproject.az.myapp.activities.MainLogIn.onCreate(MainLogIn.java:46)
                                                                             at android.app.Activity.performCreate(Activity.java:6679)
                                                                             at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
                                                                             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
                                                                             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
                                                                             at android.app.ActivityThread.-wrap12(ActivityThread.java) 
                                                                             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
                                                                             at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                             at android.os.Looper.loop(Looper.java:154) 
                                                                             at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                             at java.lang.reflect.Method.invoke(Native Method) 
                                                                             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

Answer 1

看看这一行

Caused by: java.lang.ClassCastException: android.support.design.widget.TextInputEditText cannot be cast to android.support.design.widget.TextInputLayout

它告诉您，您正在尝试将TextInputEditText类型的对象转换为TextInputLayout。

现在，请看下一行：

at com.myiscaeproject.az.myapp.activities.MainLogIn.initViews(MainLogIn.java:54)

它告诉你，它发生在MainLogIn.java文件的第54行。

学习阅读堆栈跟踪，它有很多帮助。

Answer 2

如果您阅读了错误/异常，则可以看到java.lang.ClassCastException: android.support.design.widget.TextInputEditText cannot be cast to android.support.design.widget.TextInputLayout

我想在你的活动文件中你试图将TextInputEditText分配给TextInputLayout。请使用findViewById检查您分配的位置。

我的应用程序一直停在Android模拟器中

2 个答案: