Leider hat MyApp gestoppt. Wie kann ich das lösen ..?

Question

Dies ist meine zweite Frage, weil die erste Frage, alle Klassen nicht in der Lage war

I beginnt entwickeln zu fangen, und ich war mit diesem Problem steckt leider gestoppt ____has. Wie kann ich das lösen?

dies logcat:

04-04 16:36:25.270 1906-1906/? I/art: Late-enabling -Xcheck:jni 
04-04 16:36:25.496 1906-1926/com.example.user01.myapplicationnew D/OpenGLRenderer: Render dirty regions requested: true 
04-04 16:36:25.508 1906-1906/com.example.user01.myapplicationnew D/Atlas: Validating map... 
04-04 16:36:25.537 1906-1926/com.example.user01.myapplicationnew D/libEGL: loaded /system/lib/egl/libEGL_emulation.so 
04-04 16:36:25.538 1906-1926/com.example.user01.myapplicationnew D/libEGL: loaded /system/lib/egl/libGLESv1_CM_emulation.so 
04-04 16:36:25.541 1906-1926/com.example.user01.myapplicationnew D/libEGL: loaded /system/lib/egl/libGLESv2_emulation.so 
04-04 16:36:25.574 1906-1926/com.example.user01.myapplicationnew I/OpenGLRenderer: Initialized EGL, version 1.4 
04-04 16:36:25.629 1906-1926/com.example.user01.myapplicationnew D/OpenGLRenderer: Enabling debug mode 0 
04-04 16:36:25.665 1906-1926/com.example.user01.myapplicationnew W/EGL_emulation: eglSurfaceAttrib not implemented 
04-04 16:36:25.665 1906-1926/com.example.user01.myapplicationnew W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xe2b19200, error=EGL_SUCCESS 
04-04 16:36:26.257 1906-1906/com.example.user01.myapplicationnew I/Choreographer: Skipped 34 frames! The application may be doing too much work on its main thread. 
04-04 16:36:30.056 1906-1906/com.example.user01.myapplicationnew D/AndroidRuntime: Shutting down VM 
04-04 16:36:30.056 1906-1906/com.example.user01.myapplicationnew E/AndroidRuntime: FATAL EXCEPTION: main 
                        Process: com.example.user01.myapplicationnew, PID: 1906 
                        android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.user01.myapplicationnew/com.example.user01.myapplicationnew.LoginActivity}; have you declared this activity in your AndroidManifest.xml? 
                         at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1761) 
                         at android.app.Instrumentation.execStartActivity(Instrumentation.java:1485) 
                         at android.app.Activity.startActivityForResult(Activity.java:3736) 
                         at android.app.Activity.startActivityForResult(Activity.java:3697) 
                         at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:843) 
                         at android.app.Activity.startActivity(Activity.java:4007) 
                         at android.app.Activity.startActivity(Activity.java:3975) 
                         at com.example.user01.myapplicationnew.MainActivity.onClick(MainActivity.java:51) 
                         at android.view.View.performClick(View.java:4756) 
                         at android.view.View$PerformClick.run(View.java:19749) 
                         at android.os.Handler.handleCallback(Handler.java:739) 
                         at android.os.Handler.dispatchMessage(Handler.java:95) 
                         at android.os.Looper.loop(Looper.java:135) 
                         at android.app.ActivityThread.main(ActivityThread.java:5221) 
                         at java.lang.reflect.Method.invoke(Native Method) 
                         at java.lang.reflect.Method.invoke(Method.java:372) 
                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) 
                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694) 

dies mein manifest.xml

<?xml version="1.0" encoding="utf-8"?> 

<application 



android:allowBackup="true" 
    android:icon="@mipmap/ic_launcher" 
    android:label="@string/app_name" 
    android:supportsRtl="true" 
    android:theme="@style/Theme.AppCompat"> 
    <activity 
     android:name=".MainActivity" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme.NoActionBar"> 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
</application> 

Answer 1

Diese Zeile in Ihrem logcat sagt Ihnen, was das Problem ist, :

ActivityNotFoundException: Unable to find explicit activity class {com.example.user01.myapplicationnew/com.example.user01.myapplicationnew.LoginActivity}; have you declared this activity in your AndroidManifest.xml? 

Sie haben in Ihrem Manifest LoginActivity nicht deklariert.