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  • Adding image to RichTextBox programatically does not show in Xaml property

    - by rotary_engine
    Trying to add an image to a RichTextBox progamatically from a Stream. The image displays in the text box, however when reading the Xaml property there is no markup for the image. private void richTextBox3_Drop(object sender, DragEventArgs e) { if (e.Data.GetDataPresent(DataFormats.FileDrop)) { FileInfo[] files = (FileInfo[])e.Data.GetData(DataFormats.FileDrop); using (Stream s = files[0].OpenRead()) { InlineUIContainer container = new InlineUIContainer(); BitmapImage bmp = new BitmapImage(); bmp.SetSource(s); Image img = new Image(); img.SetValue(Image.SourceProperty, bmp); container.Child = img; richTextBox3.Selection.Insert(container); } } } private void Button_Click_1(object sender, RoutedEventArgs e) { // this doesn't have the markup from the inserted image System.Windows.MessageBox.Show(richTextBox3.Xaml); } What is the correct way to insert an image into the RichTextBox at runtime so that it can be persisted to a data store? In the Xaml property.

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  • How to bind DataTable to Chart series?

    - by user175908
    Hello, How to do bind data from DataTable to Chart series? I get null reference exception. I tried binding with square brackets and it did not worked either. So, how to do the binding? Thanks. P.S: I included DataGrid XAML and CS which works just fine. Converting data to List<KeyValuePair<string,int>> works good but it is kinda slow and is unnessesary trash in code. I use WPFToolkit (the latest version). XAML: <Window x:Class="BindingzTest.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="606" Width="988" xmlns:charting="clr-namespace:System.Windows.Controls.DataVisualization.Charting;assembly=System.Windows.Controls.DataVisualization.Toolkit"> <Grid Name="LayoutRoot"> <charting:Chart Title="Letters and Numbers" VerticalAlignment="Top" Height="400"> <charting:Chart.Series> <charting:ColumnSeries Name="myChartSeries" IndependentValueBinding="{Binding Letter}" DependentValueBinding="{Binding Number}" ItemsSource="{Binding}" /> </charting:Chart.Series> </charting:Chart> <DataGrid Name="myDataGrid" VerticalAlignment="Stretch" Margin="0,400,0,50" ItemsSource="{Binding}" AutoGenerateColumns="False"> <DataGrid.Columns> <DataGridTextColumn Header="Letter" Binding="{Binding Letter}"/> <DataGridTextColumn Header="Number" Binding="{Binding Number}"/> </DataGrid.Columns> </DataGrid> <Button Content="Generate" HorizontalAlignment="Left" Name="generateButton" Width="128" Click="GenerateButtonClicked" Height="52" VerticalAlignment="Bottom" /> </Grid> CS: public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); } DataTable GenerateMyTable() { var myTable = new DataTable("MyTable"); myTable.Columns.Add("Letter"); myTable.Columns.Add("Number"); myTable.Rows.Add("A", 500); myTable.Rows.Add("B", 400); myTable.Rows.Add("C", 500); myTable.Rows.Add("D", 600); myTable.Rows.Add("E", 300); myTable.Rows.Add("F", 200); return myTable; } private void GenerateButtonClicked(object sender, RoutedEventArgs e) { var myGeneratedTable = GenerateMyTable(); myDataGrid.DataContext = myGeneratedTable; myChartSeries.DataContext = myGeneratedTable; // Calling this throws "Object reference not set to an instance of an object" exception } }

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  • Looking for a good example usage of get_or _create in Django views and raising a Form error

    - by Rik Wade
    I am looking for a good example of how to achieve the following: I would like to use get_or_create to check whether an object already exists in my database. If it does not, then it will be created. If it does exist, then I will not create the new object, but need to raise a form error to inform the user that they need to enter different data (for example, a different username). The view contains: p, created = Person.objects.get_or_create( email = registration_form.cleaned_data['email'], defaults = { 'creationDate': datetime.datetime.now(), 'dateOfBirth': datetime.date(1970,1,1) }) So 'p' will contain the existing Person if it exists, or the new Person if not. I would like to act on the boolean value in 'created' in order to skip over saving the Person and re-display the registration_form and raise an appropriate form validation error. The alternative I'm considering is doing a check in a custom Form validation method to see whether a Person exists with the data in the provided 'email' field, and just raising a validation error.

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  • XmlDocument from LINQ to XML query

    - by Ben
    I am loading an XML document into an XDocument object, doing a query and then returning the data through a web service as an XmlDocument object. The code below works fine, but it just seems a bit smelly. Is there a cleaner way to take the results of the query and convert back to an XDocument or XmlDocument? XDocument xd = XDocument.Load(Server.MapPath(accountsXml)); var accounts = from x in xd.Descendants("AccountsData") where userAccounts.Contains(x.Element("ACCOUNT_REFERENCE").Value) select x; XDocument xd2 = new XDocument( new XDeclaration("1.0", "UTF-8", "yes"), new XElement("Accounts") ); foreach (var account in accounts) xd2.Element("Accounts").Add(account); return xd2.ToXmlDocument();

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  • prevent bots to query my database several times

    - by Alain
    Hi all, I'm building an application that is a kind of registry. Think about the dictionary: you lookup for a word and it return something if the word is founded. Now, that registry is going to store valuable informations about companies, and some could be tempted to get the complete listing. My application use EJB 3.0 that replies to WS. So I was thinking about permits a maximum of 10 query per IP address per day. Storing the IP address and a counter on a table that would be empty by a script every night. Is it a good idea/practice to do so? If yes, how can I get the IP address on the EJB side? Is there a better way to prevent something to get all the data from my database? I've also though about CAPTCHA but I think it's a pain for the user, and sometime, they are difficult to read even for real human. Hope it's all clear since I'm not english... Thanks Alain

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  • Adding 90000 XElement to XDocument

    - by Jon
    I have a Dictionary<int, MyClass> It contains 100,000 items 10,000 items value is populated whilst 90,000 are null. I have this code: var nullitems = MyInfoCollection.Where(x => x.Value == null).ToList(); nullitems.ForEach(x => LogMissedSequenceError(x.Key + 1)); private void LogMissedSequenceError(long SequenceNumber) { DateTime recordTime = DateTime.Now; var errors = MyXDocument.Descendants("ERRORS").FirstOrDefault(); if (errors != null) { errors.Add( new XElement("ERROR", new XElement("DATETIME", DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss:fff")), new XElement("DETAIL", "No information was read for expected sequence number " + SequenceNumber), new XAttribute("TYPE", "MISSED"), new XElement("PAGEID", SequenceNumber) ) ); } } This seems to take about 2 minutes to complete. I can't seem to find where the bottleneck might be or if this timing sounds about right? Can anyone see anything to why its taking so long?

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  • Display vimeo in fancybox , trouble in IE

    - by Alexander Corotchi
    Hi all, i have a problem with VIMEO video . I want to display it in fancybox : this is HTML : <a href="#content" class="zoom">test</a> <div id="content" style="display:none;"> <object width="504" height="280" data="http://vimeo.com/moogaloop.swf" type="application/x-shockwave-flash"> <param value="always" name="allowscriptaccess"><param value="true" name="allowfullscreen"> <param value="http://vimeo.com/moogaloop.swf" name="movie"> <param value="clip_id=6999704&amp;server=vimeo.com&amp;fullscreen=1&amp;show_title=1&amp;show_byline=1&amp;show_portrait=1&amp;color=00ADEF" name="flashvars"> </object> </div> and js: $(document).ready(function() { $("a.zoom").fancybox(); }); Can somebody help me with this , maybe somebody knows hot to fix it .. Thanks !!

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  • CoffeeScript Class Properties Within Nested Anonymous Functions

    - by Aric
    I'm just taking a look at CoffeeScript for the first time so bare with me if this is a dumb question. I'm familiar with the hidden pattern methodology however I'm still wrapping my head around object prototypes. I'm trying to create a basic class for controlling a section on my site. The problem I'm running into is losing defined class variables within a different scope. For example, the code below works fine and creates the properties within the object perfectly. However when I jump into a jQuery callback I lose all knowledge of the class variables storing some of the jQuery objects for multiple uses. Is there a way to grab them from within the callback function? class Session initBinds: -> @loginForm.bind 'ajax:success', (data, status, xhr) -> console.log("processed") return @loginForm.bind 'ajax:before', (xhr, settings) -> console.log @loader // need access to Session.loader return return init: -> @loginForm = $("form#login-form") @loader = $("img#login-loader") this.initBinds() return

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  • Converting C# void* to byte[]

    - by Yurik
    In C#, I need to write T[] to a stream, ideally without any additional buffers. I have a dynamic code that converts T[] (where T is a no-objects struct) to a void* and fixes it in memory, and that works great. When the stream was a file, I could use native Windows API to pass the void * directly, but now I need to write to a generic Stream object that takes byte[]. Can anyone suggest a hack way to create a dummy array object which does not actually have any heap allocations, but rather points to an already existing (and fixed) heap location. This is the pseudo-code that I need: void Write(Stream stream, T[] buffer) { fixed( void* ptr = &buffer ) // done with dynamic code generation { int typeSize = sizeof(T); // done as well byte[] dummy = (byte[]) ptr; // <-- how do I create this fake array? stream.Write( dummy, 0, buffer.Length*typeSize ); } }

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  • Is this (Lock-Free) Queue Implementation Thread-Safe?

    - by Hosam Aly
    I am trying to create a lock-free queue implementation in Java, mainly for personal learning. The queue should be a general one, allowing any number of readers and/or writers concurrently. Would you please review it, and suggest any improvements/issues you find? Thank you. import java.util.concurrent.atomic.AtomicReference; public class LockFreeQueue<T> { private static class Node<E> { E value; volatile Node<E> next; Node(E value) { this.value = value; } } private AtomicReference<Node<T>> head, tail; public LockFreeQueue() { // have both head and tail point to a dummy node Node<T> dummyNode = new Node<T>(null); head = new AtomicReference<Node<T>>(dummyNode); tail = new AtomicReference<Node<T>>(dummyNode); } /** * Puts an object at the end of the queue. */ public void putObject(T value) { Node<T> newNode = new Node<T>(value); Node<T> prevTailNode = tail.getAndSet(newNode); prevTailNode.next = newNode; } /** * Gets an object from the beginning of the queue. The object is removed * from the queue. If there are no objects in the queue, returns null. */ public T getObject() { Node<T> headNode, valueNode; // move head node to the next node using atomic semantics // as long as next node is not null do { headNode = head.get(); valueNode = headNode.next; // try until the whole loop executes pseudo-atomically // (i.e. unaffected by modifications done by other threads) } while (valueNode != null && !head.compareAndSet(headNode, valueNode)); T value = (valueNode != null ? valueNode.value : null); // release the value pointed to by head, keeping the head node dummy if (valueNode != null) valueNode.value = null; return value; }

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  • str is not callable error in python .

    - by mekasperasky
    import sys import md5 from TOSSIM import * from RadioCountMsg import * t = Tossim([]) #The Tossim object is defined here m = t.mac()#The mac layer is defined here , in which the communication takes place r = t.radio()#The radio communication link object is defined here , as the communication needs Rf frequency to transfer t.addChannel("RadioCountToLedsC", sys.stdout)# The various channels through which communication will take place t.addChannel("LedsC", sys.stdout) #The no of nodes that would be required in the simulation has to be entered here print("enter the no of nodes you want ") n=input() for i in range(0, n): m = t.getNode(i) m.bootAtTime((31 + t.ticksPerSecond() / 10) * i + 1) #The booting time is defined so that the time at which the node would be booted is given f = open("topo.txt", "r") #The topography is defined in topo.txt so that the RF frequencies of the transmission between nodes are are set lines = f.readlines() for line in lines: s = line.split() if (len(s) > 0): if (s[0] == "gain"): r.add(int(s[1]), int(s[2]), float(s[3])) #The topogrography is added to the radio object noise = open("meyer-heavy.txt", "r") #The noise model is defined for the nodes lines = noise.readlines() for line in lines: str = line.strip() if (str != ""): val = int(str) for i in range(0, 4): t.getNode(i).addNoiseTraceReading(val) for i in range (0, n): t.getNode(i).createNoiseModel() #The noise model is created for each node for i in range(0,n): t.runNextEvent() fk=open("key.txt","w") for i in range(0,n): if i ==0 : key=raw_input() fk.write(key) ak=key key=md5.new() key.update(str(ak)) ak=key.digest() fk.write(ak) fk.close() fk=open("key.txt","w") plaint=open("pt.txt") for i in range(0,n): msg = RadioCountMsg() msg.set_counter(7) pkt = t.newPacket()#A packet is defined according to a certain format print("enter message to be transported") ms=raw_input()#The message to be transported is taken as input #The RC5 encryption has to be done here plaint.write(ms) pkt.setData(msg.data) pkt.setType(msg.get_amType()) pkt.setDestination(i+1)#The destination to which the packet will be sent is set print "Delivering " + " to" ,i+1 pkt.deliver(i+1, t.time() + 3) fk.close() print "the key to be displayed" ki=raw_input() fk=open("key.txt") for i in range(0,n): if i==ki: ms=fk.readline() for i in range(0,n): msg=RadioCountMsg() msg.set_counter(7) pkt=t.newPacket() msg.data=ms pkt.setData(msg.data) pkt.setType(msg.get_amType()) pkt.setDestination(i+1) pkt.deliver(i+1,t.time()+3) #The key has to be broadcasted here so that the decryption can take place for i in range(0, n): t.runNextEvent(); this code gives me error here key.update(str(ak)) . when i run a similar code on the python terminal there is no such error but this code pops up an error . why so?

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  • Selecting data from SQL Server table according to Month

    - by MarceloRamires
    I have to come up with a way to get data from a SQL server table given it's month There's a smalldatetime type field called "date" in the "events" table and a field from it looks like this: 29/01/2003 17:00:00 It should be one among those that appear in the gridview when I select jan/03 in a given DropDownList control in ASP.NET. What would be the best way to do this? Assuming I only want to go as long as 10 years to the past, wouldn't making a dictionary be a good way? How do I change it so the top month is always the current, and each month another options appeaars in the dropdown ? It should be a common issue, so that shall not be a trick, but I want a good and clean way of doing this, and (since I'm new to asp.net) I myself would come up with something messy after a long time trying. So what I want is: -Select -Best way of populating DropDownList (with the current month always at the top) -Best way to bind the DropDownList user-friendly way of writing months to the select query-friendly way of writing datetimes Info: ASP.NET, (C# or VB.NET), SQL Server 2005

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  • WinForms Form won't close on pressing X or Close() in C#

    - by MadBoy
    I'm having a bit weird problem with WinForm which seems to refuse to close for some weird reason. I've got very simple gui which sometimes doesn't react for me pressing X or when i use events on buttons it even reaches Close() and does nothing.. private void buttonZapisz_Click(object sender, EventArgs e) { string plik = textBoxDokumentDoZaladowania.Text; if (File.Exists(plik)) { string extension = Path.GetExtension(plik); string nazwaPliku = Path.GetFileName(plik); SqlMethods.databaseFilePut(plik, comboBoxTypDokumentu.Text, textBoxKomentarz.Text, sKlienciID, sPortfelID, extension, nazwaPliku); Close(); } } There are no events assigned to FormClosed or FormClosing. So how can I find out what's wrong. Sometimes X will work after the GUI is loaded but after i press Button to save some stuff to database it reaches Close() in that button event and it still is visible and does nothing. Can't use X, nor ALT+F4. I can go around GUI and choose other values for ComboBox without problem. I call GUI like this: private void contextMenuDokumentyDodaj_Click(object sender, EventArgs e) { var lv = (ListView) contextMenuDokumenty.SourceControl; string varPortfelID = Locale.ustalDaneListViewKolumny(listViewNumeryUmow, 0); string varKlienciID = Locale.ustalDaneListViewKolumny(listViewKlienci, 0); if (lv == listViewDokumentyPerKlient) { if (varKlienciID != "") { var dokumenty = new DocumentsGui(varKlienciID); dokumenty.Show(); dokumenty.FormClosed += varDocumentsGuiKlienci_FormClosed; } } else if (lv == listViewDokumentyPerPortfel) { if (varPortfelID != "" && varKlienciID != "") { var dokumenty = new DocumentsGui(varKlienciID, varPortfelID); dokumenty.Show(); dokumenty.FormClosed += varDocumentsGuiPortfele_FormClosed; } } } While I can't close GUI i can work on the main gui without problem too. I can open up same GUI and after opening new GUI i can quickly close it. GUI is very simple with few ComboBoxes,TextBoxes and one EditButton from Devexpress. Edit: varDocumentsGuiPortfele_FormClosed code allows me to refresh GUI (reload ListView's depending on where the user is on now). private void varDocumentsGuiPortfele_FormClosed(object sender, FormClosedEventArgs e) { TabControl varTabControl = tabControlKlientPortfele; if (varTabControl.TabPages.IndexOf(tabPageDokumentyPerKlient) == varTabControl.SelectedIndex) { loadTabControlKlientPortfeleBezZmianyUmowy(); } }

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  • Generic collection as a Java method argument

    - by Guido
    Is there any way to make this work in Java? public static void change(List<? extends Object> list, int position1, int position2) { Object obj = list.get(position1); list.set(position1, list.get(position2)); list.set(position2, obj); } The only way I've successfully avoided warnings and errors is this: public static <T> T change(List<T> list, int position1, int position2) { T obj = list.get(position1); list.set(position1, list.get(position2)); list.set(position2, obj); return obj; } but I don't like to be forced to return a value.

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  • Why does python use 'magic methods'?

    - by Greg Beech
    I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available an object implements a method def __len__(self) and then it is called when you write len(obj). I was just wondering why objects don't simply define a len(self) method and have it called directly as a member of the object, e.g. obj.len()? I'm sure there must be good reasons for Python doing it the way it does, but as a newbie I haven't worked out what they are yet.

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  • Python: convert buffer type of SQLITE column into string

    - by Volatil3
    I am new to Python 2.6. I have been trying to fetch date datetime value which is in yyyy-mm-dd hh:m:ss format back in my Python program. On checking the column type in Python I get the error: 'buffer' object has no attribute 'decode'. I want to use the strptime() function to split the date data and use it but I can't find how to convert a buffer to string. The following is a sample of my code (also available here): conn = sqlite3.connect("mrp.db.db", detect_types=sqlite3.PARSE_DECLTYPES) cursor = conn.cursor() qryT = """ SELECT dateDefinitionTest FROM t WHERE IDproject = 4 AND IDstatus = 5 ORDER BY priority, setDate DESC """ rec = (4,4) cursor.execute(qryT,rec) resultsetTasks = cursor.fetchall() cursor.close() # closing the resultset for item in resultsetTasks: taskDetails = {} _f = item[10].decode("utf-8") The exception I get is: 'buffer' object has no attribute 'decode'

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  • zoom_changed only triggers once in google maps api version 3 using MVC

    - by fredrik
    Hi, I'm trying to use the MVC objects in google maps version 3. What I can't seem to figure out is why my zoom_changed method is only invoked once. When I first load the map the zoom_changed method is invoked. But not when I zoom on the map. function MarkerWidget (options) { this.setValues(options); this.set('zoom', this.map.zoom); var marker = new google.maps.Marker({ icon : this.icon, mouseOverIcon : this.mouseOverIcon, orgIcon : this.orgIcon }); marker.bindTo('map', this); marker.bindTo('position', this); google.maps.event.addListener(marker, 'mouseover', this.onmouseover); google.maps.event.addListener(marker, 'mouseout', this.onmouseout); } MarkerWidget.prototype = new google.maps.MVCObject(); MarkerWidget.prototype.zoom_changed = function () { $.log(this, new Date()); } Shouldn't the map object fire the zoom event and notify all object's that has "this.set('zoom', this.map.zoom)" ? ..fredrik

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  • Stop SWF file from repeating

    - by Samuel
    Hey people, I have converted a short clip to an .swf file, i want to implement it on my website: <object width="400" height="300"> <param name="movie" value="movie.swf"> <embed src="movie.swf" width="400" height="300"> </embed> </object> When i play it it autoplays (that's fine) but it also keeps repeating over and over, i'd like it to stop at the end and just display the end frame (as mentioned i converted a movie so i cant do it with actionscript in the .fla file). Thanks for any tips!

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  • jQuery won't parse my JSON from AJAX query

    - by littlecharva
    Hi, I'm having difficulty parsing some JSON data returned from my server using jQuery.ajax() To perform the AJAX I'm using: $.ajax({ url: myUrl, cache: false, dataType: "json", success: function(data){ ... }, error: function(e, xhr){ ... } }); And if I return an array of items then it works fine: [ { title: "One", key: "1" }, { title: "Two", key: "2" } ] The success function is called and receives the correct object. However, when I'm trying to return a single object: { title: "One", key: "1" } The error function is called and xhr contains 'parsererror'. I've tried wrapping the JSON in parenthesis on the server before sending it down the wire, but it makes no difference. Yet if I paste the content into a string in Javascript and then use the eval() function, it evaluates it perfectly. Any ideas what I'm doing wrong? Anthony

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  • MouseLeave event in Silverlight 3 PopUp control

    - by AKa
    I want use PopUp (System.Windows.Controls.Primitives.PopUp) control to show some context menu. After mouse leaves, should automatically close. But eventhandler for MouseLeave is never executed. Why? SAMPLE: void DocumentLibrary_Loaded(object sender, RoutedEventArgs e) { DocumentLibraryDialog documentLibraryDialog = new DocumentLibraryDialog(); _popUpDocumentLibraryDialog = new Popup(); _popUpDocumentLibraryDialog.Width = 70; _popUpDocumentLibraryDialog.Height = 20; _popUpDocumentLibraryDialog.MouseLeave += new MouseEventHandler(_popUpDocumentLibraryDialog_MouseLeave); _popUpDocumentLibraryDialog.Child = documentLibraryDialog; } void _popUpDocumentLibraryDialog_MouseLeave(object sender, MouseEventArgs e) { Popup currentPopUp = (Popup)sender; if (currentPopUp.IsOpen) (currentPopUp.IsOpen) = false; } Regards Anton Kalcik

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  • Silverlight 4 accessing WCF Data Services: BeginInvoke frustrations.

    - by Gatmando
    Hi, I'm attempting to follow a pattern for performing WCF data service queries using the Silverlight 4 beta. The following is my code: public CodeTables() { CodeCountries = new ObservableCollection<dsRealHomes.CodeCountries>(); dsRealHomes.RealHomesEntities myClient = null; myClient = staticGlobals.RealHomesContext(); object userState = null; myClient.BeginExecute<dsRealHomes.CodeCountries>(new Uri("CodeCountries"), (IAsyncResult asyncResult) => { Dispatcher.BeginInvoke( () => { var test = myClient.EndExecute<dsRealHomes.CodeCountries>asyncResult).ToList(); } ); }, userState); } This is derived from a number of examples I've come across for WCF data services with silverlight. Unfortunately no matter how I try to implement the code i end up with the following error on 'Dispatcher.BeginInvoke': 'An object reference is required for the non-static field, method, or property (System.Windows.Threading.Dispatcher.BeginInvoke(System.Action)' Thanks

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  • (VB.NET + WPF) Drag + Drop (to allow user sorting) of stackpanel elements within a Scrollviewer?

    - by Matt H.
    I have good model (I think!) for how to allow a user to drag an element in a stackpanel and reposition it to another location within the stackpanel. However, my Stackpanel is placed within a ScrollViewer, like this (generalized): <ScrollViewer> <StackPanel> ....First item ....Second item ....Third item ....Etc. </StackPanel> <ScrollViewer> Here is the problem, I wish to simulate the functionality of programs like word, where if I am dragging selected content (or an object) outside the viewable area, the window will scroll in the direction of the mouse to see more places to drop my nifty little object. ...i.e. If I move the mouse to the top of my ScrollViewer while dragging a stackpanel's contents, I want the scrollviewer to slowly move up so I can see more locations to drop my content. Any suggestions? If you can help me solve this, you will be a godsend!

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  • Erasing and modifying elements in Boost MultiIndex Container

    - by Sarah
    I'm trying to use a Boost MultiIndex container in my simulation. My knowledge of C++ syntax is very weak, and I'm concerned I'm not properly removing an element from the container or deleting it from memory. I also need to modify elements, and I was hoping to confirm the syntax and basic philosophy here too. // main.cpp ... #include <boost/multi_index_container.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/mem_fun.hpp> #include <boost/tokenizer.hpp> #include <boost/shared_ptr.hpp> ... #include "Host.h" // class Host, all members private, using get fxns to access using boost::multi_index_container; using namespace boost::multi_index; typedef multi_index_container< boost::shared_ptr< Host >, indexed_by< hashed_unique< const_mem_fun<Host,int,&Host::getID> > // ordered_non_unique< BOOST_MULTI_INDEX_MEM_FUN(Host,int,&Host::getAge) > > // end indexed_by > HostContainer; typedef HostContainer::nth_index<0>::type HostsByID; int main() { ... HostContainer allHosts; Host * newHostPtr; newHostPtr = new Host( t, DOB, idCtr, 0, currentEvents ); allHosts.insert( boost::shared_ptr<Host>(newHostPtr) ); // allHosts gets filled up int randomHostID = 4; int newAge = 50; modifyHost( randomHostID, allHosts, newAge ); killHost( randomHostID, allHosts ); } void killHost( int id, HostContainer & hmap ){ HostsByID::iterator it = hmap.find( id ); cout << "Found host id " << (*it)->getID() << "Attempting to kill. hmap.size() before is " << hmap.size() << " and "; hmap.erase( it ); // Is this really erasing (freeing from mem) the underlying Host object? cout << hmap.size() << " after." << endl; } void modifyHost( int id, HostContainer & hmap, int newAge ){ HostsByID::iterator it = hmap.find( id ); (*it) -> setAge( newAge ); // Not actually the "modify" function for MultiIndex... } My questions are In the MultiIndex container allHosts of shared_ptrs to Host objects, is calling allHosts.erase( it ) on an iterator to the object's shared_ptr enough to delete the object permanently and free it from memory? It appears to be removing the shared_ptr from the container. The allhosts container currently has one functioning index that relies on the host's ID. If I introduce an ordered second index that calls on a member function (Host::getAge()), where the age changes over the course of the simulation, is the index always going to be updated when I refer to it? What is the difference between using the MultiIndex's modify to modify the age of the underlying object versus the approach I show above? I'm vaguely confused about what is assumed/required to be constant in MultiIndex. Thanks in advance. Update Here's my attempt to get the modify syntax working, based on what I see in a related Boost example. struct update_age { update_age():(){} // have no idea what this really does... elicits error void operator() (boost::shared_ptr<Host> ptr) { ptr->incrementAge(); // incrementAge() is a member function of class Host } }; and then in modifyHost, I'd have hmap.modify(it,update_age). Even if by some miracle this turns out to be right, I'd love some kind of explanation of what's going on.

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  • C# generic list <T> how to get the type of T?

    - by Daok
    Hello, Let say I have a List< T > abc = new List< T >; inside a class public class MyClass<T>//.... Later, when I initialize the class the T because MyTypeObject1. So I have a generic list of List< MyTypeObject1 >. I would like to know, what type of object the list of my class contain. Example, the list called abc contain what type of object? I cannot do abc[0].GetType(); because the list might contain 0 element. How can I do it?

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