Develop Reference

Skipped 675 frames! The application may be doing too much work on its main thread. How to make app run process in background without freezing the UI?

I have an news aggregator and in debug i have the following:
Skipped 675 frames! The application may be doing too much work on its main thread.
I am loading only from 12 sites. Is there a way to to do all this loading in background without the whole app freezing?
EDIT:
Method to get one news
public async static Task<NewsContent> oneNews(string category,string site)
{
if(sites.Count==0)
addElements();
GetNews gn = new GetNews(site,false);
Random rn = new Random();
var s = await gn.news(rn.Next(0,2));
return s;
}
The GetNews class:
class GetNews
{
string url;
bool isMultiple;
public GetNews(string url,bool isMultiple)
{
this.url = url;
this.isMultiple = isMultiple;
}
public async Task<NewsContent> news(int i)
{
List<NewsContent> feedItemsList = new List<NewsContent>();
try
{
WebRequest webRequest = WebRequest.Create(url);
WebResponse webResponse = webRequest.GetResponse();
Stream stream = webResponse.GetResponseStream();
XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Load(stream);
XmlNamespaceManager nsmgr = new XmlNamespaceManager(xmlDocument.NameTable);
nsmgr.AddNamespace("dc", xmlDocument.DocumentElement.GetNamespaceOfPrefix("dc"));
nsmgr.AddNamespace("content", xmlDocument.DocumentElement.GetNamespaceOfPrefix("content"));
XmlNodeList itemNodes = xmlDocument.SelectNodes("rss/channel/item");
NewsContent feedItem = new NewsContent();
if (itemNodes[i].SelectSingleNode("title") != null)
{
feedItem.title = itemNodes[i].SelectSingleNode("title").InnerText;
}
if (itemNodes[i].SelectSingleNode("link") != null)
{
feedItem.url = itemNodes[i].SelectSingleNode("link").InnerText;
}
if (itemNodes[i].SelectSingleNode("pubDate") != null)
{
var time = itemNodes[i].SelectSingleNode("pubDate").InnerText;
feedItem.time = getHour(time);
}
if (itemNodes[i].SelectSingleNode("description") != null)
{
feedItem.desc = itemNodes[i].SelectSingleNode("description").InnerText;
}
if (itemNodes[i].SelectSingleNode("content:encoded", nsmgr) != null)
{
feedItem.content = itemNodes[i].SelectSingleNode("content:encoded", nsmgr).InnerText;
}
else
{
feedItem.content = feedItem.desc;
}
feedItem.imageURL = getImage(feedItem.content);
var sourcename = url.Split(new[] { "//" }, StringSplitOptions.None)[1];
feedItem.newsSource = sourcename.Split(new[] { "/" }, StringSplitOptions.None)[0];
if (feedItem.content.Contains("<p>"))
{
var shortContent = feedItem.content.Split(new[] { "<p>" }, StringSplitOptions.None)[1];
string finalShortContent = "";
for (int ii = 0; ii < shortContent.Length; ii++)
{
if (ii > 200 && shortContent[ii].Equals(' '))
break;
while (shortContent[ii].Equals('<') || shortContent[ii].Equals('p') || shortContent[ii].Equals('/') || shortContent[ii].Equals('>'))
ii++;
try
{
finalShortContent += shortContent[ii];
}
catch (Exception e)
{
break;
}
}
finalShortContent += "...";
feedItem.shortcontent = finalShortContent;
}
return feedItem;
}
catch (Exception e)
{
return null;
}
}
string getImage(string full)
{
try
{
var code = full.Split(new[] { "src=\"" }, StringSplitOptions.None)[1];
var fin = code.Split(new[] { "\"" }, StringSplitOptions.None)[0];
return fin;
}
catch(Exception e)
{
return null;
}
}
List<int> getHour(string full)
{
try
{
List<int> smh = new List<int>();
var ph = full.Split(new[] { "2020 " }, StringSplitOptions.None)[1];
var hour = ph.Split(new[] { ":" }, StringSplitOptions.None);
smh.Add(Int32.Parse(hour[0]));
smh.Add(Int32.Parse(hour[1]));
var second = hour[2].Split(new[] { " " }, StringSplitOptions.None)[0];
smh.Add(Int32.Parse(second));
return smh;
}catch(Exception)
{
return null;
}
}
}

Try this. It should put the function in another thread
await Task.Run(async () =>
{
//function
});

Message body empty on quickblox ios in xamarin native c#

i've translated the quickblox's sample app for Xamarin forms in Xamarin iOS and Android native.
Everything works "except" that the retrieving of the message fails.
I send the message from one client, and the event is catched from the other chat occupant:
XMPP: DispatchEvents ====> <message id="580735ed335fb760ae0017ec" xmlns="jabber:client" from="18029700-46533#chat.quickblox.com/1220770403-quickblox-68179" type="chat" to="18976912-46533#chat.quickblox.com"><extraParams xmlns="jabber:client"><save_to_history>1</save_to_history><dialog_id>5800aea1a28f9a1c1f000010</dialog_id><message_id>580735ed335fb760ae0017ec</message_id><date_sent>1476867565</date_sent></extraParams><body>test+message</body><thread>5800aea1a28f9a1c1f000010</thread></message>
XMPP: OnMessageReceived ====> From: 18029700 To: 18976912 Body: DateSent 1476867565 FullXmlMessage: <message id="580735ed335fb760ae0017ec" xmlns="jabber:client" from="18029700-46533#chat.quickblox.com/1220770403-quickblox-68179" type="chat" to="18976912-46533#chat.quickblox.com"><extraParams xmlns="jabber:client"><save_to_history>1</save_to_history><dialog_id>5800aea1a28f9a1c1f000010</dialog_id><message_id>580735ed335fb760ae0017ec</message_id><date_sent>1476867565</date_sent></extraParams><body>test+message</body><thread>5800aea1a28f9a1c1f000010</thread></message>
as you can see the Body part into the event OnMessageReceived is empty!
But the html part in the end of this snippet contains the message "test+message"
this is the PrivateChat Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using QbChat.Pcl.Repository;
using Quickblox.Sdk.GeneralDataModel.Models;
using Quickblox.Sdk.Modules.ChatXmppModule;
using Quickblox.Sdk.Modules.UsersModule.Models;
using UIKit;
using Xmpp.Im;
namespace KeepInTouch.iOS
{
public partial class PrivateChat : BaseChat
{
PrivateChatManager privateChatManager;
public PrivateChat(string dialogId, string nibname) : base(dialogId, nibname) { }
public async override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
AppDelegate.R.NavController.SetNavigationBarHidden(true, true);
await MessageProvider.Reconnect();
}
public override void ViewDidLoad()
{
base_tb_chat = tb_chat;
base_txt_chat = txt_chat;
base.ViewDidLoad();
view_top.BackgroundColor = UIColor.FromPatternImage(UIImage.FromFile("navbar_top_kit.png"));
tb_chat.TableFooterView = new UIView();
IsBusyIndicatorVisible = true;
var dialog = Database.Instance().GetDialog(dialogId);
var opponentId = dialog.OccupantIds.Split(',').Select(int.Parse).First(id => id != QbChat.UserId);
ChatXmppClient xmpc = QbChat.QbProvider.GetXmppClient();
privateChatManager = xmpc.GetPrivateChatManager(opponentId, dialogId);
privateChatManager.MessageReceived += OnMessageReceived;
DialogName = dialog.Name;
//xmpc.MessageReceived += OnMessageReceived;
btn_chat.TouchUpInside += async delegate {
await SendMessageCommandExecute();
txt_chat.Text = "";
};
txt_chat.ShouldReturn += (textField) => {
textField.ResignFirstResponder();
return true;
};
txt_chat.EditingChanged += async delegate {
MessageText = txt_chat.Text;
await MessageProvider.Reconnect();
};
btn_back.TouchUpInside += delegate {
DismissViewController(false, null);
};
IsBusyIndicatorVisible = true;
Task.Factory.StartNew(async () => {
var users = await QbChat.QbProvider.GetUsersByIdsAsync(dialog.OccupantIds);
var opponentUser = users.FirstOrDefault(u => u.Id != QbChat.UserId);
if (opponentUser != null && opponentUser.BlobId.HasValue) {
await QbChat.QbProvider.GetImageAsync(opponentUser.BlobId.Value).ContinueWith((task, result) => {
//var bytes =
task.ConfigureAwait(true).GetAwaiter().GetResult();
}, TaskScheduler.FromCurrentSynchronizationContext());
}
opponentUsers = new List<User> { opponentUser };
await LoadMessages();
InvokeOnMainThread(() =>
IsBusyIndicatorVisible = false
);
});
}
async void OnMessageReceived(object sender, MessageEventArgs messageEventArgs)
{
if (messageEventArgs.MessageType == MessageType.Chat ||
messageEventArgs.MessageType == MessageType.Groupchat) {
string decodedMessage = System.Net.WebUtility.UrlDecode(messageEventArgs.Message.MessageText);
var messageTable = new MessageTable();
messageTable.SenderId = messageEventArgs.Message.SenderId;
messageTable.DialogId = messageEventArgs.Message.ChatDialogId;
messageTable.DateSent = messageEventArgs.Message.DateSent;
if (messageEventArgs.Message.NotificationType != 0) {
if (messageEventArgs.Message.NotificationType == NotificationTypes.GroupUpdate) {
if (messageEventArgs.Message.AddedOccupantsIds.Any()) {
var userIds = new List<int>(messageEventArgs.Message.AddedOccupantsIds);
userIds.Add(messageEventArgs.Message.SenderId);
var users = await QbChat.QbProvider.GetUsersByIdsAsync(string.Join(",", userIds));
var addedUsers = users.Where(u => u.Id != messageEventArgs.Message.SenderId);
var senderUser = users.First(u => u.Id == messageEventArgs.Message.SenderId);
messageTable.Text = senderUser.FullName + " added users: " + string.Join(",", addedUsers.Select(u => u.FullName));
} else if (messageEventArgs.Message.DeletedOccupantsIds.Any()) {
var userIds = new List<int>(messageEventArgs.Message.DeletedOccupantsIds);
var users = await QbChat.QbProvider.GetUsersByIdsAsync(string.Join(",", userIds));
messageTable.Text = string.Join(",", users.Select(u => u.FullName)) + " left this room";
}
//var dialogInfo = await QbChat.QbProvider.GetDialogAsync(messageEventArgs.Message.ChatDialogId);
//if (dialogInfo == null)
//{
// return;
//}
//var dialog = new DialogTable(dialogInfo);
//Database.Instance().SaveDialog(dialog);
}
} else {
messageTable.Text = decodedMessage;
}
await SetRecepientName(messageTable);
Messages.Add(messageTable);
InvokeOnMainThread(async () => {
tb_chat.ReloadData();
await ScrollList();
});
}
}
public async Task LoadMessages()
{
List<Message> messages;
try {
messages = await QbChat.QbProvider.GetMessagesAsync(dialogId);
} catch (Exception ex) {
Console.WriteLine(ex);
return;
}
if (messages != null) {
messages = messages.OrderBy(message => message.DateSent).ToList();
foreach (var message in messages) {
var chatMessage = new MessageTable();
chatMessage.DateSent = message.DateSent;
chatMessage.SenderId = message.SenderId;
chatMessage.MessageId = message.Id;
if (message.RecipientId.HasValue)
chatMessage.RecepientId = message.RecipientId.Value;
chatMessage.DialogId = message.ChatDialogId;
chatMessage.IsRead = message.Read == 1;
await SetRecepientName(chatMessage);
chatMessage.Text = System.Net.WebUtility.UrlDecode(message.MessageText);
InvokeOnMainThread(() =>
Messages.Add(chatMessage)
);
}
InvokeOnMainThread(async () => {
tb_chat.ReloadData();
await ScrollList();
});
}
}
async Task SendMessageCommandExecute()
{
var message = MessageText != null ? MessageText.Trim() : string.Empty;
if (!string.IsNullOrEmpty(message)) {
var m = new MessageTable();
m.SenderId = QbChat.UserId;
m.Text = message;
m.DialogId = dialogId;
m.RecepientFullName = "Me";
try {
await MessageProvider.Reconnect();
var encodedMessage = System.Net.WebUtility.UrlEncode(message);
privateChatManager.SendMessage(encodedMessage);
} catch (Exception ex) {
Console.WriteLine(ex);
return;
}
long unixTimestamp = DateTime.UtcNow.Ticks - new DateTime(1970, 1, 1).Ticks;
unixTimestamp /= TimeSpan.TicksPerSecond;
m.DateSent = unixTimestamp;
m.ID = Database.Instance().SaveMessage(m);
var dialog = Database.Instance().GetDialog(dialogId);
dialog.LastMessage = m.Text;
dialog.LastMessageSent = DateTime.UtcNow;
Database.Instance().SaveDialog(dialog, true);
Messages.Add(m);
MessageText = "";
InvokeOnMainThread(async () => {
tb_chat.ReloadData();
await ScrollList();
});
}
}
public override void DidReceiveMemoryWarning()
{
base.DidReceiveMemoryWarning();
}
}
}
long story short the sdk receive the message but apparently fail to parse the body message. fire the handler but if empty don't call the privateChatManager.MessageReceived.
could anyone help please?
Thank you

How to make an "apprequest" with c# Facebook SDK?

I would like to make an apprequest from my application using the c# facebook sdk.
After some investigation I found some examples that are using the app access token which has the following format : access_token = YOUR_APP_ID|YOU_APP_SECRET
Now I have tried the following using the appAccessToken:
string appAccessToken = String.Format("{0}|{1}",Constants.FacebookAppId,Constants.FacebookAppSecret);
FacebookClient fb = new FacebookClient(appAccessToken);
fb.PostCompleted += (o, args) =>
{
if (args.Error != null)
{
Dispatcher.BeginInvoke(() => MessageBox.Show(args.Error.Message));
return;
}
};
dynamic parameters = new ExpandoObject();
parameters.message = "Test: Action is required";
parameters.data = "Custom Data Here";
fb.PostTaskAsync(String.Format("{0}/apprequests", Constants.FacebookAppId), parameters);
But it doesn't work... Is it possible to make an apprequest using the c# Facebook skd?
I hope anybody can help me.
Have a nice day!
With best regards, Matthias

To get access token of App.
Just use this link and you will get it
https://developers.facebook.com/tools/access_token/
Please check this out : http://facebooksdk.net/docs/phone/tutorial.
To get user access token
Add this to App.xaml.cs
internal static string AccessToken = String.Empty;
internal static string FacebookId = String.Empty;
public static bool IsAuthenticated = false;
public static FacebookSessionClient FacebookSessionClient = new FacebookSessionClient(Constants.FacebookAppId);
Create a method to get Access token
private async Task Authenticate()
{
try
{
_session = await App.FacebookSessionClient.LoginAsync("user_about_me,read_stream");
App.AccessToken = _session.AccessToken;
App.FacebookId = _session.FacebookId;
}
catch (InvalidOperationException e)
{
var messageBox = new OneButtonCustomMessageBox
{
TbMessageTitle = { Text = "Facebook Login Error" },
TbMessageContent = {Text = e.Message}
};
messageBox.Show();
}
}
After you have Access Token you will use a method like this to call GraphAPI from FB to get user information
private async void LoadUserInfo()
{
var fb = new FacebookClient(App.AccessToken);
fb.GetCompleted += (o, e) =>
{
if (e.Error != null)
{
Dispatcher.BeginInvoke(() => MessageBox.Show(e.Error.Message));
return;
}
var result = (IDictionary<string, object>)e.GetResultData();
Dispatcher.BeginInvoke(async () =>
{
var profilePictureUrl = string.Format("https://graph.facebook.com/{0}/picture?type={1}&access_token={2}", App.FacebookId, "normal", App.AccessToken);
this.ImgAvatar.Source = new BitmapImage(new Uri(profilePictureUrl));
this.TxtName.Text = String.Format("{0}", (string)result["name"]);
});
};
await fb.GetTaskAsync("me");
}

How to deal with multiple EventHandlers to AsyncQuery

I am working on Windows Phone 8 project. In my project there are 10 Events with 10 EventHandlers ReverseGeocodeQuery_QueryCompleted (1 to 10). When first EventHandler is completed it turn on second event.
What should I implement to manage those Events without so much code.
code
myReverseGeocodeQuery = new ReverseGeocodeQuery();
myReverseGeocodeQuery.GeoCoordinate = mySimulationCoordinates.ElementAt(0);
myReverseGeocodeQuery.QueryCompleted += ReverseGeocodeQuery_QueryCompleted_1;
myReverseGeocodeQuery.QueryAsync();
private void ReverseGeocodeQuery_QueryCompleted_1(object sender, QueryCompletedEventArgs<IList<MapLocation>> e)
{
if (e.Error == null)
{
if (e.Result.Count > 0)
{
MapAddress address = e.Result[0].Information.Address;
label8txt.Text = address.City.ToString() + "\n" + address.Street.ToString();
StringBuilder str = new StringBuilder();
str.AppendLine("Pierwszy");
str.AppendLine("11" + address.HouseNumber);
str.AppendLine("17" + address.Street);
MessageBox.Show(str.ToString());
}
myReverseGeocodeQuery = new ReverseGeocodeQuery();
myReverseGeocodeQuery.GeoCoordinate = mySimulationCoordinates.ElementAt(1);
myReverseGeocodeQuery.QueryCompleted += ReverseGeocodeQuery_QueryCompleted_2;
myReverseGeocodeQuery.QueryAsync();
}
}
private void ReverseGeocodeQuery_QueryCompleted_2(object sender, QueryCompletedEventArgs<IList<MapLocation>> e)
{
if (e.Error == null)
{
if (e.Result.Count > 0)
{
MapAddress address = e.Result[0].Information.Address;
label8txt.Text = address.City.ToString() + "\n" + address.Street.ToString();
StringBuilder str = new StringBuilder();
str.AppendLine("Drugi");
str.AppendLine("11" + address.HouseNumber);
str.AppendLine("17" + address.Street);
MessageBox.Show(str.ToString());
myReverseGeocodeQuery = new ReverseGeocodeQuery();
myReverseGeocodeQuery.GeoCoordinate = mySimulationCoordinates.ElementAt(2);
myReverseGeocodeQuery.QueryCompleted += ReverseGeocodeQuery_QueryCompleted_3;
myReverseGeocodeQuery.QueryAsync();
}
}
}
Example Solution 1
public class DataContainer
{
public string Description { get; set; }
public GeoCoordinate Coordinate { get; set; }
//public List<GeoCoordinate> mySimulationCoordinates { get; set; }
public String EnterSimulation() {
StringBuilder strRet = new StringBuilder();
List<GeoCoordinate> mySimulationCoordinates = new List<GeoCoordinate>();
mySimulationCoordinates.Add(new GeoCoordinate(51.760752, 19.458216));
mySimulationCoordinates.Add(new GeoCoordinate(51.760757, 19.458356));
mySimulationCoordinates.Add(new GeoCoordinate(51.760738, 19.458442));
mySimulationCoordinates.Add(new GeoCoordinate(51.7607, 19.458501));
mySimulationCoordinates.Add(new GeoCoordinate(51.760662, 19.458533));
var descriptions = new[] { "Pierwszy", "Drugi", "Trzeci", "Czwarty", "Piąty" }; //etc
var zipped = mySimulationCoordinates.Zip(descriptions, (coord, desc) => new DataContainer { Description = desc, Coordinate = coord });
int k = zipped.Count();
foreach (var item in zipped)
{
var currentItem = item;
using (var waitHandle = new AutoResetEvent(false))
{
var geocodeQuery = new ReverseGeocodeQuery();
geocodeQuery.GeoCoordinate = item.Coordinate;
geocodeQuery.QueryCompleted += (sender, args) =>
{
if (args.Error == null)
{
if (args.Result.Count > 0)
{
MapAddress address = args.Result[0].Information.Address;
//label8txt.Text = address.City.ToString() + "\n" + address.Street.ToString();
StringBuilder str = new StringBuilder();
str.AppendLine(currentItem.Description);
str.AppendLine("House Number" + address.HouseNumber);
str.AppendLine("Street " + address.Street);
strRet.AppendLine("->");
strRet.Append(str);
waitHandle.Set();
}
}
};
geocodeQuery.QueryAsync();
waitHandle.WaitOne();
}
}
return strRet.ToString();
}
It stuck on 1st item. Is inside and wait ... wait ... can't pass to next element.

Umm... Let's see, shouldn't that be easier?
Warning: untested
public class DataContainer
{
public string Description {get;set;}
public GeoCoordinate Coordinate {get;set;}
}
var descriptions = new[] {"Pierwszy" , "Drugi" , "Trzeci" }; //etc
var zipped = mySimulationCoordinates.Zip(descriptions, (coord, desc) => new DataContainer { Description = desc, Coordinate = coord });
foreach(var item in zipped)
{
var currentItem = item;
using(var waitHandle = new AutoResetEvent(false))
{
var geocodeQuery = new ReverseGeocodeQuery();
geocodeQuery.GeoCoordinate = currentItem.Coordinates;
geocodeQuery.QueryCompleted += (sender, args) => {
if (e.Error == null)
{
if (e.Result.Count > 0)
{
MapAddress address = args.Result[0].Information.Address;
label8txt.Text = address.City.ToString() + "\n" + address.Street.ToString();
StringBuilder str = new StringBuilder();
str.AppendLine(currentItem.Description);
str.AppendLine("11" + address.HouseNumber);
str.AppendLine("17" + address.Street);
MessageBox.Show(str.ToString());
waitHandle.Set();
}
}
};
geoCodeQuery.QueryAsync();
waitHandle.WaitOne();
}
}
That should guarantee you that one event is handled after another in order.

Need help to get Access Token

Here, I am using user id generated by facebook in place of appid . Am I correct here??
As I wanted to get access token with the help of user name and password for my application designed in windows forms. I am using below code to fetch it. Please, give me any better solution to fetch access token.
string appId = userid.ToString();
string[] extendedPermissions = new[] { "publish_stream", "offline_access" };
var oauth = new FacebookOAuthClient { ClientId = appId };
var parameters = new Dictionary<string, object> {
{ "response_type", "token" }, { "display", "popup" } };
if (extendedPermissions != null && extendedPermissions.Length > 0)
{
var scope = new StringBuilder();
scope.Append(string.Join(",", extendedPermissions));
parameters["scope"] = scope.ToString();
}
var loginUrl = oauth.GetLoginUrl(parameters);
wbTestWindow.Navigate(loginUrl);
// this webBrowser's related navigated function
private void wbTestWindow_Navigated(object sender, WebBrowserNavigatedEventArgs e)
{
FacebookOAuthResult result;
if (FacebookOAuthResult.TryParse(e.Url, out result))
{
if (result.IsSuccess)
{
var accesstoken = result.AccessToken;
}
else
{
var errorDescription = result.ErrorDescription;
var errorReason = result.ErrorReason;
}
}
}