使用Google MapsV2扩展SupportMapFragment会导致ClassNotFoundException

Question

• android-support-v4.jar
• google-play-services_lib.jar
• google-play-services.jar
• Android jar是target 4.2也是Android-17平台

我有以下错误：

java.lang.RuntimeException: Unable to start activity \
       ComponentInfo{app.cookingplace/app.cookingplace.MapsActivity}: \
       android.view.InflateException: Binary XML file line #8: \
       Error inflating class fragment
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:130)
    at android.app.ActivityThread.main(ActivityThread.java:3687)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
    at dalvik.system.NativeStart.main(Native Method)

Caused by: android.view.InflateException: Binary XML file line #8: \
       Error inflating class fragment
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:587)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:209)
    at android.app.Activity.setContentView(Activity.java:1657)
    at app.cookingplace.MapsActivity.onCreate(MapsActivity.java:12)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
    ... 11 more

Caused by: android.support.v4.app.Fragment$InstantiationException: \
       Unable to instantiate fragment com.google.android.gms.maps.SupportMapFragment: \
       make sure class name exists, is public, and has an empty constructor that is public
    at android.support.v4.app.Fragment.instantiate(Fragment.java:401)
    at android.support.v4.app.Fragment.instantiate(Fragment.java:369)
    at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:272)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:563)
    ... 20 more

Caused by: java.lang.ClassNotFoundException: com.google.android.gms.maps.SupportMapFragment in loader \
       dalvik.system.PathClassLoader[/system/framework/com.google.android.maps.jar:\
       /data/app/app.cookingplace-2.apk]
    at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:551)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
    at android.support.v4.app.Fragment.instantiate(Fragment.java:391)
    ... 23 more

我的代码：

package app.cookingplace;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class LoginActivity extends Activity implements OnClickListener {

    // All static variables
    static final String baseURL = "http://sfsuswe.com/~f12g22/web/php/Login.php?";
    String URL = "";
    // XML node keys
    static final String KEY_SESSION = "session"; // parent node
    static final String KEY_ACTIVATED = "activate";
    String activated = "";
    static final String KEY_REGISTERED = "registered";
    String registered = "";
    static final String KEY_USERID = "userId";
    String userId = "";
    static final String KEY_LOGONNAME = "logonName";
    String logonName = "";

    private Button login_button;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        login_button = (Button) findViewById(R.id.login_button);
        login_button.setOnClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_login, menu);
        return true;
    }

    @Override
    public void onClick(View arg0) {
        EditText nameLogin = (EditText) findViewById(R.id.user_logon_id);
        String loginName = nameLogin.getText().toString();
        EditText passwordLogin = (EditText) findViewById(R.id.password_logon_id);
        String password = passwordLogin.getText().toString();

        String parameters = "logon=" + loginName + "&password=" + password;
        URL = baseURL + parameters;

        XMLParser parser = new XMLParser();
        String xml = parser.getXmlFromUrl(URL); // getting XML
        Document doc = parser.getDomElement(xml); // getting DOM element

        NodeList nl = doc.getElementsByTagName(KEY_SESSION);

        Element e = (Element) nl.item(0);
        // adding each child node to HashMap key => value
        activated = parser.getValue(e, KEY_ACTIVATED);
        registered = parser.getValue(e, KEY_REGISTERED);
        userId = parser.getValue(e, KEY_USERID);
        logonName = parser.getValue(e, KEY_LOGONNAME);

        if (registered.equals("1")) {
        Intent nextScreen = new Intent(LoginActivity.this,
                MapsActivity.class);
        startActivityForResult(nextScreen, 0);
        }
    }
}

MapsActivity.java

     package app.cookingplace;

     import android.os.Bundle;
     import android.support.v4.app.FragmentActivity;
     import android.view.Menu;

     public class MapsActivity extends FragmentActivity {

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

            @Override
            public boolean onCreateOptionsMenu(Menu menu) {
                // Inflate the menu; this adds items to the action bar if it is present.
                getMenuInflater().inflate(R.menu.activity_maps, menu);
                return true;
            }
        }

activity_login.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LoginActivity" >

<EditText
    android:id="@+id/user_logon_id"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:ems="10"
    android:inputType="textPersonName"
    android:text="@string/user_login" >

    <requestFocus />
</EditText>

<EditText
    android:id="@+id/password_logon_id"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_below="@+id/user_logon_id"
    android:ems="10"
    android:inputType="textPassword"
    android:text="@string/password_login" />

<Button
    android:id="@+id/login_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_below="@+id/password_logon_id"
    android:text="@string/button_login" />

activity_maps.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MapsActivity" >

    <fragment
        class="com.google.android.gms.maps.SupportMapFragment"
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
/>

</RelativeLayout>

AndroidManifest.xml

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

    <permission
        android:name="app.cookingplace.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />

    <uses-permission android:name="app.cookingplace.permission.MAPS_RECEIVE" />
    <!-- Copied from Google Maps Library/AndroidManifest.xml. -->
    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="16" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
    <!-- External storage for caching. -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <!-- My Location -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <!-- Maps API needs OpenGL ES 2.0. -->
    <uses-feature
        android:glEsVersion="0x00020000"
        android:required="true" />
    <!-- End of copy. -->

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <meta-data
            android:name="com.google.android.maps.v2.API_KEY"
            android:value="-My key tested and works fine-" />

        <activity
            android:name="app.cookingplace.LoginActivity"
            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="app.cookingplace.MapActivity"
            android:label="@string/title_activity_map" >
        </activity>
        <activity
            android:name="app.cookingplace.TestActivity"
            android:label="@string/title_activity_test" >
        </activity>
        <activity
            android:name="app.cookingplace.MapsActivity"
            android:label="@string/title_activity_maps" >
            </activity>
        <uses-library android:name="com.google.android.maps" />
    </application>

</manifest>

Answer 1

 public class MapsActivity extends Activity

public class MapsActivity extends FragmentActivity