显然,当我调用getMap()
时,它触发了NullPointerException
。我在SO上看到了许多其他解决方案,但它们对我不起作用。
我什至尝试使用计时器并仅运行getMap()
,但应用程序在5秒钟后崩溃,这是我在计时器上设置的延迟。我想在地图上设置当前位置。地图加载没有问题,但是当我尝试getMap()
应用程序因NPE而崩溃时,我却没问题。
MapActivity类
package com.integratedprogram2nd;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import com.google.android.gms.maps.*;
public class MapActivity extends FragmentActivity {
GoogleMap map;
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
SupportMapFragment mapFrag = (SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.map);
map = mapFrag.getMap();
map.setMyLocationEnabled(true);
}
}
activity_map.xml(仅5行)
<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"/>
Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.integratedprogram2nd"
android:versionCode="4"
android:versionName="1.3" >
<uses-sdk
android:minSdkVersion="11"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:icon="@drawable/icon"
android:label="GPS Logger Professional"
android:theme="@style/AppTheme" >
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="intentionally blanked out"/>
<activity
android:name=".MainActivity"
android:label="GPS Logger Professional" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".BatteryTemp"
android:label="@string/title_activity_battery_temp" >
</activity>
<activity
android:name=".Settings"
android:label="@string/title_activity_settings" >
</activity>
<activity
android:name="com.google.android.gms.ads.AdActivity"
android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" />
<activity
android:name=".MapActivity"
android:label="GPS Logger Professional" >
</activity>
</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="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-feature
android:glEsVersion="0x00020000"
android:required="true"/>
</manifest>
最佳答案
使用SupportMapFragment代替MapFragment:
<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.SupportMapFragment"/>