我曾经使用IntentService创建AlarmService，它执行另一个类TakeUserData。该类发出一些HTTP请求。当应用程序打开时，一切正常，但在关闭过程后，我在每次服务调用时都会收到java.lang.NullPointerException。
这里的logcat：
01-23 16:27:00.999 18276-18290/com.eugnis.vktrace W/System.err﹕ java.lang.NullPointerException
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.VKRequest.getLang(VKRequest.java:548)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.VKRequest.getPreparedParameters(VKRequest.java:274)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.httpClient.VKHttpClient.requestWithVkRequest(VKHttpClient.java:127)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.VKRequest.getPreparedRequest(VKRequest.java:297)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.VKRequest.getOperation(VKRequest.java:311)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.vk.sdk.api.VKBatchRequest.executeWithListener(VKBatchRequest.java:76)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.eugnis.vktrace.TakeUserData.<init>(TakeUserData.java:91)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at com.eugnis.vktrace.CheckUsersService.onHandleIntent(CheckUsersService.java:107)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at android.os.Handler.dispatchMessage(Handler.java:102)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at android.os.Looper.loop(Looper.java:157)
01-23 16:27:01.009 18276-18290/com.eugnis.vktrace W/System.err﹕ at android.os.HandlerThread.run(HandlerThread.java:61)
和IntentService类：
package com.eugnis.vktrace;
...
public class CheckUsersService extends IntentService {
SaveUserData dbHelper;
SQLiteDatabase db;
TakeUserData take;
public CheckUsersService() {
super("CheckUsersService");
}
public int onStartCommand(Intent intent, int flags, int startId){
Log.d("ABAB", "ON START COMMAND");
try {
dbHelper = new SaveUserData(this);
db = dbHelper.getWritableDatabase();
Cursor c = db.query("users", null, null, null, null, null, null);
if (c.moveToFirst()) {
int useridColIndex = c.getColumnIndex("userid");
do {
int userID = c.getInt(useridColIndex);
take = new TakeUserData(this, userID, 1,1,1,1,1,1,1);
} while (c.moveToNext());
} else
Log.d("VkDemoApp", "0 rows");
c.close();
Log.v(this.getClass().getName(), "Timed alarm onReceive() started at time: " + new java.sql.Timestamp(System.currentTimeMillis()).toString());
}
catch (Exception e) {
e.printStackTrace();
}
return 1;
}
@Override
protected void onHandleIntent(Intent intent) {
Log.d("ABAB", "INTENT STARTED");
}
}
TakeUserData：
public class TakeUserData {
SaveUserData dbHelper;
String selection = null;
String[] selectionArgs = null;
int online=0, friends=0, status=0, pagedata=0, photovideo=0, music=0, groups=0, posts=0;
VKApiUserFull userInfo;
Context context;
private static final int NOTIFY_ID = 101;
public TakeUserData(Context v, final int userID, final int chkonline, final int chkfriends, final int chkpagedata, final int chkphotovideo, final int chkmusic, final int chkgroups, final int chkposts)
{
context=v;
dbHelper = new SaveUserData(context);
final SQLiteDatabase db = dbHelper.getWritableDatabase();
Log.d("VkDemoApp", "--- Rows in mytable: ---");
selection = "userid="+userID;
Cursor c = db.query("users", null, selection, null, null, null, null);
if(c.getCount()==1) {
if (c.moveToFirst()) {
int onlineColIndex = c.getColumnIndex("online");
int friendsColIndex = c.getColumnIndex("friends");
// int statusColIndex = c.getColumnIndex("status");
int pagedataColIndex = c.getColumnIndex("pagedata");
int photovideoColIndex = c.getColumnIndex("photovideo");
int musicColIndex = c.getColumnIndex("music");
int groupsColIndex = c.getColumnIndex("groups");
int postsColIndex = c.getColumnIndex("posts");
online = c.getInt(onlineColIndex);
friends = c.getInt(friendsColIndex);
pagedata = c.getInt(pagedataColIndex);
photovideo = c.getInt(photovideoColIndex);
music = c.getInt(musicColIndex);
groups = c.getInt(groupsColIndex);
posts = c.getInt(postsColIndex);
} else
Log.d("VkDemoApp", "0 rows");
c.close();
}
if (c.moveToFirst()) {
VKRequest requestUserInformation = VKApi.users().get(VKParameters.from(VKApiConst.USER_ID, userID, VKApiConst.FIELDS, "photo_200, counters, last_seen, status, photo_id, city, contacts, education, relatives, relation, personal, connections, activities, interests, music, movies, tv, books, games, about, quotes"));
VKRequest requestUserPosts = VKApi.wall().get(VKParameters.from(VKApiConst.OWNER_ID, userID));
VKBatchRequest batch = new VKBatchRequest(requestUserInformation, requestUserPosts);
batch.executeWithListener(new VKBatchRequest.VKBatchRequestListener() { //Error from this column
@Override
public void onComplete(VKResponse[] responses) {
String tlast_seen=null, tfriends_count=null, tsubscribers_count=null, tphoto_200=null, tcity=null, tmobile_phone=null, thome_phone=null,
trelatives=null, trelation=null, tpersonal=null, tconnections=null, tactivities=null, tinterests=null, tmovies=null, ttv=null, tbooks=null,
tgames=null, tabout=null, tquotes=null, tphoto_count=null, tvideo_count=null, tmusic_count=null, tgroups_count=null, tposts_count=null;
super.onComplete(responses);
Log.d("VkDemoApp", "TakeResp1 " + responses[0].json.toString());
Log.d("VkDemoApp", "TakeResp2 " + responses[1].json);
userInfo = ((VKList<VKApiUserFull>)responses[0].parsedModel).get(0);
String[] arrayPosts = responses[1].json.toString().split("(?<=\\D)(?=\\d)|(?<=\\d)(?=\\D)");
...
}
@Override
public void onError(VKError error) {
Toast.makeText(context, "Error" + error.toString(), Toast.LENGTH_SHORT).show();
}
});
} else
Log.d("VkDemoApp", "0 rows");
c.close();
}
选中在没有HTTP请求的情况下启动 - 一切都很好。我确定这是因为HTTP请求但我不知道如何修复它。
VKRequest.getLang
private String getLang() {
String result = mPreferredLang;
if (useSystemLanguage) {
result = VKUIHelper.getApplicationContext().getResources().getConfiguration().locale.getLanguage();
if (result.equals("uk")) {
result = "ua";
}
if (!Arrays.asList(new String[]{"ru", "en", "ua", "es", "fi", "de", "it"})
.contains(result)) {
result = mPreferredLang;
}
}
return result;
}
VKUIHelper.java
public class VKUIHelper {
private static Activity sTopActivity;
private static Context sApplicationContext;
public static Activity getTopActivity()
{
return sTopActivity;
}
public static Context getApplicationContext() { return sApplicationContext; }
/**
* Call it in onCreate for of activities where you using VK SDK
* @param activity Your activity
*/
public static void onCreate(Activity activity)
{
if (sTopActivity != activity)
sTopActivity = activity;
if (sApplicationContext == null && activity != null) {
sApplicationContext = activity.getApplicationContext();
}
}
/**
* Call it in onResume for of activities where you using VK SDK
* @param activity Your activity
*/
public static void onResume(Activity activity)
{
if (sTopActivity != activity)
sTopActivity = activity;
if (sApplicationContext == null && activity != null) {
sApplicationContext = activity.getApplicationContext();
}
}
/**
* Call it in onDestroy for of activities where you using VK SDK
* @param activity Your activity
*/
public static void onDestroy(Activity activity)
{
if (sTopActivity == activity)
sTopActivity = null;
}
/**
* Call it in onActivityResult of all activities where you using VK SDK
* @param requestCode Request code for startActivityForResult
* @param resultCode Result code of finished activity
* @param data Result data
* @deprecated Use onActivityResult(Activity activity, int requestCode, int resultCode, Intent data) instead
*/
public static void onActivityResult(int requestCode, int resultCode, Intent data)
{
onActivityResult(sTopActivity, requestCode, resultCode, data);
}
/**
* Call it in onActivityResult of all activities where you using VK SDK
* @param requestCode Request code for startActivityForResult
* @param resultCode Result code of finished activity
* @param data Result data
*/
public static void onActivityResult(Activity activity, int requestCode, int resultCode, Intent data) {
sTopActivity = activity;
if (requestCode == VKSdk.VK_SDK_REQUEST_CODE) {
VKSdk.processActivityResult(requestCode, resultCode, data);
}
}
}