您好我正在android中创建一个社交网络，我从mysql数据中获取数据并将其放入listview适配器但是我需要自动刷新listview并通知如果有新的插入数据，我正在使用广播接收器和服务但是它什么都没发生请帮助我 这是我的代码
Broadcast receiver
public class BraodcastReceiverNotif extends BroadcastReceiver {
static int noOfTimes = 0;
JSONObject data;
Exception exception;
SharedPreferences sharedpreferences;;
public static final String mypreference = "pkAppPrefs";
int pageNumber = 0;
public static final int REQUEST_CODE = 12345;
Intent intnt;
Context context;
@Override
public void onReceive(final Context context, Intent intent) {
sharedpreferences = context.getSharedPreferences(mypreference, Context.MODE_PRIVATE);
noOfTimes++;
//Toast.makeText(context, "BC Service Running for " + noOfTimes + " times", Toast.LENGTH_SHORT).show();
// TODO Auto-generated method stub
noOfTimes++;
try {
startNetworkCalls ();
} catch (JSONException e) {
e.printStackTrace();
}
}
private void startNetworkCalls () throws JSONException {
data = new JSONObject();
data.put("user_key", sharedpreferences.getString("userKey", ""));
data.put("city_id", sharedpreferences.getString("user_city_id", ""));
data.put("sector_id", sharedpreferences.getString("sector_id", ""));
data.put("page", pageNumber);
String URL = ".............................................";
getOnlinePosts onlinePosts = new getOnlinePosts();
onlinePosts.execute(URL);
}
private class getOnlinePosts extends AsyncTask<String, Void, String[]> {
private final String LOG_TAG =getOnlinePosts.class.getSimpleName();
private Exception exception = null;
@Override
protected void onPreExecute() {
}
@Override
protected String[] doInBackground(String... params) {
URL url;
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
String docsJson = null;
String JsonDATA = data.toString();
String JsonResponse = null;
Context context = null;
try {
Log.e(LOG_TAG, "Started Connecting to " + params[0] + " Sending " +JsonDATA);
url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setDoOutput(true);
urlConnection.setRequestMethod("POST");
urlConnection.setRequestProperty("Content-Type", "application/json");
urlConnection.setRequestProperty("Accept", "application/json");
Writer writer = new BufferedWriter(new OutputStreamWriter(urlConnection.getOutputStream(), "UTF-8"));
writer.write(JsonDATA);
writer.close();
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String inputLine;
while ((inputLine = reader.readLine()) != null)
buffer.append(inputLine + "\n");
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
docsJson = buffer.toString();
Log.v(LOG_TAG, "My data is: " + docsJson);
} catch (Exception e) {
exception = e;
e.printStackTrace();
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
}
try {
return getDocumentDataFromJson(docsJson);
} catch (JSONException e) {
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
// this will only happen if there is an error
return null;
}
@Override
protected void onPostExecute(String[] result) {
}
}
private String[] getDocumentDataFromJson(String documentJsonStrArr)
throws JSONException {
final String data_status = "status";
final String data_data = "data";
final String data_name = "fullname";
final String data_username = "community";
JSONObject documentJson = new JSONObject(documentJsonStrArr);
String status = documentJson.getString(data_status);
if (status.equals("success")) {
JSONArray docs = documentJson.getJSONArray(data_data);
if (docs.length() > 0) {
for (int i = 0; i < docs.length(); i++) {
JSONObject singleDoc = docs.getJSONObject(i);
// String success = singleDoc.getString(documentJson.getString(data_status));
String name = singleDoc.getString(data_name);
String username = singleDoc.getString(data_username);
intnt = new Intent(context, MyService.class);
// Set unsynced count in intent data
intnt.putExtra("success", "success");
intnt.putExtra("name", name);
// Call MyService
context.startService(intnt);
}
}
}
return null;
}
}
这是我的服务
public class MyService extends Service {
int numMessages = 0;
ArrayList<SinglePost> PostEntries = null;
public ArrayAdapter<SinglePost> mycardAdapter;
SharedPreferences sharedpreferences;;
public static final String mypreference = "pkAppPrefs";
public MyService() {
}
@Override
public IBinder onBind(Intent intent) {
throw new UnsupportedOperationException("Not yet implemented");
}
@Override
public void onCreate() {
Toast.makeText(this, "Service was Created", Toast.LENGTH_LONG).show();
sharedpreferences = getSharedPreferences(mypreference, Context.MODE_PRIVATE);
}
@Override
public void onStart(Intent intent, int startId) {
Toast.makeText(this, "Service Started", Toast.LENGTH_LONG).show();
Intent resultIntent = new Intent(this, Community.class);
Toast.makeText(this, intent.getStringExtra("name"), Toast.LENGTH_LONG).show();
PostEntries.add(new SinglePost(intent.getStringExtra("post_key"),
intent.getStringExtra("name"),
intent.getStringExtra("username"), intent.getStringExtra("profile_image"),intent.getStringExtra("poster_key") ,
intent.getStringExtra("postdate"),intent.getStringExtra("message") ,intent.getStringExtra("likes") ,
intent.getStringExtra("liked"),intent.getStringExtra("comments") ,intent.getStringExtra("commented") ,
Boolean.parseBoolean(intent.getStringExtra("moderate")),intent.getStringExtra("sector") ,
intent.getStringExtra("district"),intent.getStringExtra("province") ,
intent.getStringExtra("city"),intent.getStringExtra("country") ,intent.getStringExtra("media") ,
Integer.parseInt(intent.getStringExtra("media_count") ),
Integer.parseInt(intent.getStringExtra("moderate_level")) ,
Boolean.parseBoolean( intent.getStringExtra("own_post")) ,intent.getStringExtra("online")));
//if (Integer.parseInt(intent.getStringExtra("count_data")) < Integer.parseInt(sharedpreferences.getString("count_data", ""))){
PendingIntent resultPendingIntent = PendingIntent.getActivity(this, 0,
resultIntent, PendingIntent.FLAG_UPDATE_CURRENT);
NotificationCompat.Builder mNotifyBuilder;
NotificationManager mNotificationManager;
mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// Sets an ID for the notification, so it can be updated
int notifyID = 9001;
mNotifyBuilder = new NotificationCompat.Builder(this)
.setContentTitle("Alert")
.setContentText("You've received new messages.")
.setSmallIcon(R.drawable.ic_launcher);
// Set pending intent
mNotifyBuilder.setContentIntent(resultPendingIntent);
// Set Vibrate, Sound and Light
int defaults = 0;
defaults = defaults | android.app.Notification.DEFAULT_LIGHTS;
defaults = defaults | android.app.Notification.DEFAULT_VIBRATE;
defaults = defaults | android.app.Notification.DEFAULT_SOUND;
mNotifyBuilder.setDefaults(defaults);
// Set the content for Notification
mNotifyBuilder.setContentText(intent.getStringExtra("success"));
// Set autocancel
mNotifyBuilder.setAutoCancel(true);
// Post a notification
mNotificationManager.notify(notifyID, mNotifyBuilder.build());
// }
}
@Override
public void onDestroy() {
Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
}
MainActivity class i am passing scheduleAlarm method to check every 10 second in database and refresh my listview
Setup a recurring alarm every 10 seconds
public void scheduleAlarm() {
BroadCase Receiver Intent Object
Intent alarmIntent = new Intent(getContext().getApplicationContext(), BraodcastReceiverNotif.class);
// Pending Intent Object
PendingIntent pendingIntent = PendingIntent.getBroadcast(getContext().getApplicationContext(), 0, alarmIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Alarm Manager Object
AlarmManager alarmManager = (AlarmManager) getContext().getApplicationContext().getSystemService(Context.ALARM_SERVICE);
// Alarm Manager calls BroadCast for every Ten seconds (10 * 1000), BroadCase further calls service to check if new records are inserted in
// Remote MySQL DB
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, Calendar.getInstance().getTimeInMillis() + 5000, 10 * 1000, pendingIntent);
}
固定格式
答案 0 :(得分：0)
我真的不明白你的问题，但我有道理。
如果我理解正确，你想从服务器获取数据，存储在SQLite数据库中并在Listview中显示数据
要实现此功能，
你怎么能播出， 您在具有列表视图的活动中注册广播接收器。 广播只传递消息作为＆＃39;布尔＆＃39;确定从服务器获取数据的值？如果从服务器成功获取然后传递布尔值，则在广播接收之后，进行本地数据库调用并获取所有更改。之后，您可以更新列表视图