Question

该应用程序最初工作但后来停止了，因为我添加了一些其他代码，我已经撤消它，但现在旧的代码也没有工作。

我的清单

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

    <uses-sdk
        android:minSdkVersion="16"
        android:targetSdkVersion="8" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />
        <activity
            android:name="com.example.btrack.MainActivity"
            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.btrack.Inbay"
            android:label="@string/app_name" >
        </activity>
        <activity
            android:name="com.example.btrack.Inbus"
            android:label="@string/app_name" >
        </activity>
        <activity
            android:name="com.example.btrack.Bus_track"
            android:label="@string/app_name" >
        </activity>
        <meta-data
            android:name="com.google.android.maps.v2.API_KEY"
            android:value="AIzaSyDKrNEcOQfkJ2Co-YE_8B4sfXuzlSXqd7k"/>
    </application>    
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/>
    <!-- The following two permissions are not required to use
         Google Maps Android API v2, but are recommended. -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

</manifest>

我的代码

package com.example.btrack;

import android.app.Activity;
import android.os.Bundle;
public abstract class Bus_track extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bus_track);

//GoogleMap mMap;           
//mMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
//mMap.setMyLocationEnabled(true);
}
}

布局

<?xml version="1.0" encoding="utf-8"?>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
          android:id="@+id/map"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:name="com.google.android.gms.maps.MapFragment"/>

错误

04-05 22:48:10.550: I/Adreno200-EGL(10583): Reconstruct Branch: AU_LINUX_ANDROID_JB_2.3.04.01.01.032.173 +  NOTHING
04-05 22:48:13.242: W/dalvikvm(10583): threadid=1: thread exiting with uncaught exception (group=0x41d72450)
04-05 22:48:13.252: E/AndroidRuntime(10583): FATAL EXCEPTION: main
04-05 22:48:13.252: E/AndroidRuntime(10583): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.btrack/com.example.btrack.Bus_track}: java.lang.InstantiationException: can't instantiate class com.example.btrack.Bus_track
04-05 22:48:13.252: E/AndroidRuntime(10583):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1986)

使用此代码的应用程序最初正在运行。

Answer 1

更改此

 public abstract class Bus_track extends Activity {

到

 public class Bus_track extends Activity {

阅读本文

Interview: Can we instantiate abstract class?

 <uses-sdk
 android:minSdkVersion="16"
 android:targetSdkVersion="8" /> // have the latest like 19
 // Lint, if enabled, will warn you about it

另请考虑将所有<uses-permission.../>代码移至application代码

上方

阅读开发人员文档和

https://developers.google.com/maps/documentation/android/start#getting_the_google_maps_android_api_v2

错误：java.lang.RuntimeException：无法实例化活动

1 个答案: