android app unfornately stop working on the emulator

Question

I am new to Android and I have this simple app i created.But it always says Unfortunately app_name has stopped each time i try to run it on the emulator.Please help me figure out what the problem is.

my manifest file looks like this

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.pretty"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="16"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:label="@string/app_name"
            android:name=".Hello" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>
My main.xml looks like this

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="vertical" android:layout_width="fill_parent"
      android:layout_height="fill_parent">
      <TextView android:layout_width="fill_parent"
         android:layout_height="wrap_content" android:text="@string/name" />
</LinearLayout>

my Hello.java looks like this

import com.example.pretty.R;
import android.app.Activity;
import android.os.Bundle;        
public class Hello extends Activity{        
      @Override
      public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);           
      setContentView(R.layout.main);
        }        
 }

My logcat produces

07-29 22:42:52.349: E/Trace(666): error opening trace file: No such file or directory (2)
07-29 22:42:52.589: D/AndroidRuntime(666): Shutting down VM
07-29 22:42:52.619: W/dalvikvm(666): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
07-29 22:42:52.689: E/AndroidRuntime(666): FATAL EXCEPTION: main
07-29 22:42:52.689: E/AndroidRuntime(666): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.pretty/com.example.pretty.Hello}: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.os.Looper.loop(Looper.java:137)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread.main(ActivityThread.java:4745)
07-29 22:42:52.689: E/AndroidRuntime(666):  at java.lang.reflect.Method.invokeNative(Native Method)
07-29 22:42:52.689: E/AndroidRuntime(666):  at java.lang.reflect.Method.invoke(Method.java:511)
07-29 22:42:52.689: E/AndroidRuntime(666):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
07-29 22:42:52.689: E/AndroidRuntime(666):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
07-29 22:42:52.689: E/AndroidRuntime(666):  at dalvik.system.NativeStart.main(Native Method)
07-29 22:42:52.689: E/AndroidRuntime(666): Caused by: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:42:52.689: E/AndroidRuntime(666):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-29 22:42:52.689: E/AndroidRuntime(666):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-29 22:42:52.689: E/AndroidRuntime(666):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
07-29 22:42:52.689: E/AndroidRuntime(666):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
07-29 22:42:52.689: E/AndroidRuntime(666):  ... 11 more
07-29 22:42:52.779: I/Process(666): Sending signal. PID: 666 SIG: 9
07-29 22:43:17.699: D/AndroidRuntime(706): Shutting down VM
07-29 22:43:17.699: W/dalvikvm(706): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
07-29 22:43:17.729: E/AndroidRuntime(706): FATAL EXCEPTION: main
07-29 22:43:17.729: E/AndroidRuntime(706): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.pretty/com.example.pretty.Hello}: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.os.Looper.loop(Looper.java:137)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread.main(ActivityThread.java:4745)
07-29 22:43:17.729: E/AndroidRuntime(706):  at java.lang.reflect.Method.invokeNative(Native Method)
07-29 22:43:17.729: E/AndroidRuntime(706):  at java.lang.reflect.Method.invoke(Method.java:511)
07-29 22:43:17.729: E/AndroidRuntime(706):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
07-29 22:43:17.729: E/AndroidRuntime(706):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
07-29 22:43:17.729: E/AndroidRuntime(706):  at dalvik.system.NativeStart.main(Native Method)
07-29 22:43:17.729: E/AndroidRuntime(706): Caused by: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:43:17.729: E/AndroidRuntime(706):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-29 22:43:17.729: E/AndroidRuntime(706):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-29 22:43:17.729: E/AndroidRuntime(706):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
07-29 22:43:17.729: E/AndroidRuntime(706):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
07-29 22:43:17.729: E/AndroidRuntime(706):  ... 11 more
07-29 22:43:22.559: I/Process(706): Sending signal. PID: 706 SIG: 9
07-29 22:52:37.799: E/Trace(720): error opening trace file: No such file or directory (2)
07-29 22:52:38.229: D/AndroidRuntime(720): Shutting down VM
07-29 22:52:38.229: W/dalvikvm(720): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
07-29 22:52:38.259: E/AndroidRuntime(720): FATAL EXCEPTION: main
07-29 22:52:38.259: E/AndroidRuntime(720): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.pretty/com.example.pretty.Hello}: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.os.Looper.loop(Looper.java:137)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread.main(ActivityThread.java:4745)
07-29 22:52:38.259: E/AndroidRuntime(720):  at java.lang.reflect.Method.invokeNative(Native Method)
07-29 22:52:38.259: E/AndroidRuntime(720):  at java.lang.reflect.Method.invoke(Method.java:511)
07-29 22:52:38.259: E/AndroidRuntime(720):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
07-29 22:52:38.259: E/AndroidRuntime(720):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
07-29 22:52:38.259: E/AndroidRuntime(720):  at dalvik.system.NativeStart.main(Native Method)
07-29 22:52:38.259: E/AndroidRuntime(720): Caused by: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:52:38.259: E/AndroidRuntime(720):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-29 22:52:38.259: E/AndroidRuntime(720):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-29 22:52:38.259: E/AndroidRuntime(720):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
07-29 22:52:38.259: E/AndroidRuntime(720):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
07-29 22:52:38.259: E/AndroidRuntime(720):  ... 11 more
07-29 22:58:47.479: D/AndroidRuntime(734): Shutting down VM
07-29 22:58:47.479: W/dalvikvm(734): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
07-29 22:58:47.499: E/AndroidRuntime(734): FATAL EXCEPTION: main
07-29 22:58:47.499: E/AndroidRuntime(734): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.pretty/com.example.pretty.Hello}: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.os.Looper.loop(Looper.java:137)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread.main(ActivityThread.java:4745)
07-29 22:58:47.499: E/AndroidRuntime(734):  at java.lang.reflect.Method.invokeNative(Native Method)
07-29 22:58:47.499: E/AndroidRuntime(734):  at java.lang.reflect.Method.invoke(Method.java:511)
07-29 22:58:47.499: E/AndroidRuntime(734):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
07-29 22:58:47.499: E/AndroidRuntime(734):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
07-29 22:58:47.499: E/AndroidRuntime(734):  at dalvik.system.NativeStart.main(Native Method)
07-29 22:58:47.499: E/AndroidRuntime(734): Caused by: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 22:58:47.499: E/AndroidRuntime(734):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-29 22:58:47.499: E/AndroidRuntime(734):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-29 22:58:47.499: E/AndroidRuntime(734):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
07-29 22:58:47.499: E/AndroidRuntime(734):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
07-29 22:58:47.499: E/AndroidRuntime(734):  ... 11 more
07-29 23:03:47.589: I/Process(734): Sending signal. PID: 734 SIG: 9
07-29 23:28:15.169: D/AndroidRuntime(782): Shutting down VM
07-29 23:28:15.169: W/dalvikvm(782): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
07-29 23:28:15.198: E/AndroidRuntime(782): FATAL EXCEPTION: main
07-29 23:28:15.198: E/AndroidRuntime(782): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.pretty/com.example.pretty.Hello}: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread.access$600(ActivityThread.java:130)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.os.Looper.loop(Looper.java:137)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread.main(ActivityThread.java:4745)
07-29 23:28:15.198: E/AndroidRuntime(782):  at java.lang.reflect.Method.invokeNative(Native Method)
07-29 23:28:15.198: E/AndroidRuntime(782):  at java.lang.reflect.Method.invoke(Method.java:511)
07-29 23:28:15.198: E/AndroidRuntime(782):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
07-29 23:28:15.198: E/AndroidRuntime(782):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
07-29 23:28:15.198: E/AndroidRuntime(782):  at dalvik.system.NativeStart.main(Native Method)
07-29 23:28:15.198: E/AndroidRuntime(782): Caused by: java.lang.ClassNotFoundException: com.example.pretty.Hello
07-29 23:28:15.198: E/AndroidRuntime(782):  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-29 23:28:15.198: E/AndroidRuntime(782):  at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-29 23:28:15.198: E/AndroidRuntime(782):  at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
07-29 23:28:15.198: E/AndroidRuntime(782):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
07-29 23:28:15.198: E/AndroidRuntime(782):  ... 11 more

possible duplicate of [What is a stack trace, and how can I use it to debug my application errors?](http://stackoverflow.com/questions/3988788/what-is-a-stack-trace-and-how-can-i-use-it-to-debug-my-application-errors) — panini, Jul 29 '14 at 22:34
Is your `Hello.java` in the package `com.example.pretty`? If Yes, then use the link given by @panini to go debug the stack trace step by step. — rgamber, Jul 29 '14 at 22:40

score 0 · Answer 1 · answered Jul 29 '14 at 22:42

0

It's a class not found exception. Possible causes:

Reconfigure build Path
com.example.pretty.Hello does not exist / the package has a different name

answered Jul 29 '14 at 22:42

Gumbo

1,716
1
15
22

score 0 · Answer 2 · answered Jul 29 '14 at 22:44

0

You must declare the correct package at the top of Hello.java:

package com.example.pretty;

import com.example.pretty.R;
// rest of your Hello.java

answered Jul 29 '14 at 22:44

Greg Hewgill

951,095
183
1,149
1,285

android app unfornately stop working on the emulator

2 Answers2