Android::Extending MapActivity => classNotFound异常

Question

我想做一个MapView，但是扩展MapActivity会抛出一个classNotFoundException：

   /AndroidRuntime(  374):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
    E/AndroidRuntime(  374):        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
    E/AndroidRuntime(  374):        at android.app.ActivityThread.access$2300(ActivityThread.java:125)
    E/AndroidRuntime(  374):        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
    E/AndroidRuntime(  374):        at android.os.Handler.dispatchMessage(Handler.java:99)
    E/AndroidRuntime(  374):        at android.os.Looper.loop(Looper.java:123)
    E/AndroidRuntime(  374):        at android.app.ActivityThread.main(ActivityThread.java:4627)
    E/AndroidRuntime(  374):        at java.lang.reflect.Method.invokeNative(Native Method)
    E/AndroidRuntime(  374):        at java.lang.reflect.Method.invoke(Method.java:521)
    E/AndroidRuntime(  374):        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
    E/AndroidRuntime(  374):        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
    E/AndroidRuntime(  374):        at dalvik.system.NativeStart.main(Native Method)
    E/AndroidRuntime(  374): Caused by: java.lang.ClassNotFoundException: com.androidcourse.phonemapper.view.MapShowActivity in loader dalvik.system.PathClassLoader[/system/framework/com.google.android.maps.jar:/data/app/com.androidcourse.phonemapper-2.apk]
    E/AndroidRuntime(  374):        at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
    E/AndroidRuntime(  374):        at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
    E/AndroidRuntime(  374):        at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
    E/AndroidRuntime(  374):        at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
    E/AndroidRuntime(  374):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)

我有一个Google Maps API key，我已经将项目设置为Google API，我正在使用Android Google API AVD(模拟器)，我确实在我的AndroidManifest.xml中包含了标签。

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

    <uses-sdk android:minSdkVersion="8" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
    <application android:icon="@drawable/icon" android:label="@string/app_name">

  <uses-library android:name="com.google.android.maps" />

.

        <activity android:name=".view.WelcomeActivity" android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>


<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/mainlayout"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <com.google.android.maps.MapView
        android:id="@+id/mapview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:clickable="true"
        android:apiKey="api_key_is_here_just_wont_show_it_to_everybody"
    />
</RelativeLayout>

Answer 1

尝试将package设置为"com.androidcourse.phonemapper.view"：

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

然后引用它：

<activity android:name=".WelcomeActivity"

Answer 2

我在实现android:required="true“语句时遇到了完全相同的错误，这是许多教程中遗留下来的。

<uses-library
            android:name="com.google.android.maps"
            android:required="true" />

Answer 3

另外，如果您忘记将

<uses-library android:name="com.google.android.maps" />

标记中，您将获得扩展MapActivity :)的活动的ClassNotFound异常。)