不幸的是，该应用程序已停止 - LogCat 产生无数错误

Question

我对整个 Android 编程事情还是很陌生，我遇到了一个问题，即应用程序在构建后退出。几秒钟后，它退出应用程序，并显示一条消息，“不幸的是，应用程序已停止。”除此之外，LogCat 在这之后吓坏了，并打印出看似无穷无尽的问题列表，我将在此处发布。我在stackoverflow上看到了其他一些关于此的帖子，但我还没有找到解决我问题的帖子。任何帮助将不胜感激 - 非常感谢！

07-02 08:51:33.208: D/AndroidRuntime(2639): Shutting down VM
07-02 08:51:33.208: W/dalvikvm(2639): threadid=1: thread exiting with uncaught exception (group=0x411b4ac8)
07-02 08:51:33.208: E/AndroidRuntime(2639): FATAL EXCEPTION: main
07-02 08:51:33.208: E/AndroidRuntime(2639): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.helloworldtaketwo/com.example.helloworldtaketwo.main}: java.lang.ClassNotFoundException: Didn't find class "com.example.helloworldtaketwo.main" on path: /data/app/com.example.helloworldtaketwo-2.apk
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2299)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread.access$700(ActivityThread.java:154)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1284)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.os.Handler.dispatchMessage(Handler.java:99)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.os.Looper.loop(Looper.java:137)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread.main(ActivityThread.java:5306)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at java.lang.reflect.Method.invokeNative(Native Method)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at java.lang.reflect.Method.invoke(Method.java:511)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at dalvik.system.NativeStart.main(Native Method)
07-02 08:51:33.208: E/AndroidRuntime(2639): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.helloworldtaketwo.main" on path: /data/app/com.example.helloworldtaketwo-2.apk
07-02 08:51:33.208: E/AndroidRuntime(2639):     at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:65)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.Instrumentation.newActivity(Instrumentation.java:1071)
07-02 08:51:33.208: E/AndroidRuntime(2639):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2166)
07-02 08:51:33.208: E/AndroidRuntime(2639):     ... 11 more
07-02 08:51:42.127: I/Process(2639): Sending signal. PID: 2639 SIG: 9

---

我的 Android Manifest 看起来像这样：

<?xml version = "1.0" encoding = "utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.helloworldtaketwo"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="20" />

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

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

</manifest>

main.java

package thatpackage;

import com.example.helloworldtaketwo.R;

import android.app.Activity;
import android.os.Bundle;

public class main extends Activity{

    @Override
    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

}

Answer 1

您的“主要”活动必须位于“com.example.helloworldtaketwo”包中。不是子包，不在其他地方。

这里的问题是找不到您的活动。通过将其放置在正确的包中或更正清单以指向正确的包来确保其正确链接。

Answer 2

您尚未在清单中声明该类。使用这个：

<?xml version = "1.0" encoding = "utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.helloworldtaketwo"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="20" />

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

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

        <activity android:name="com.example.MyActivity2"></activity>


</application>

</manifest>

欲了解更多信息，请研究这些来源

• How to add activity in manifest file

• App Manifest

• Activities