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  • Python - wxPython custom button -> unbound method __init__()? what?

    - by Wallter
    After looking at questions like this it doesn't make sense that my __init__(self, parrent, id) would be throwing a unbound error? help? main.py import wx from customButton import customButton from wxPython.wx import * class MyFrame(wx.Frame): def __init__(self, parent, ID, title): wxFrame.__init__(self, parent, ID, title, wxDefaultPosition, wxSize(400, 400)) # Non-important code here... # This is the first declaration of the Button1 # This is also where the ERROR is thrown. # Omitting this line causes the window to execute # flawlessly. self.Button1 = customButton.__init__(self, parent, -1) # ... finishes in a basic wx.program style... customButton.py # I've included all of the code in the file # because have no idea where the bug/error happens import wx from wxPython.wx import * class Custom_Button(wx.PyControl): # The BMP's Over_bmp = None #wxEmptyBitmap(1,1,1) # When the mouse is over Norm_bmp = None #wxEmptyBitmap(1,1,1) # The normal BMP Push_bmp = None #wxEmptyBitmap(1,1,1) # The down BMP def __init__(self, parent, id, **kwargs): wx.PyControl.__init__(self,parent, id, **kwargs) # Set the BMP's to the ones given in the constructor #self.Over_bmp = wx.Bitmap(wx.Image(MOUSE_OVER_BMP, wx.BITMAP_TYPE_ANY).ConvertToBitmap()) #self.Norm_bmp = wx.Bitmap(wx.Image(NORM_BMP, wx.BITMAP_TYPE_ANY).ConvertToBitmap()) #self.Push_bmp = wx.Bitmap(wx.Image(PUSH_BMP, wx.BITMAP_TYPE_ANY).ConvertToBitmap()) #self.Pos_bmp = self.pos self.Bind(wx.EVT_LEFT_DOWN, self._onMouseDown) self.Bind(wx.EVT_LEFT_UP, self._onMouseUp) self.Bind(wx.EVT_LEAVE_WINDOW, self._onMouseLeave) self.Bind(wx.EVT_ENTER_WINDOW, self._onMouseEnter) self.Bind(wx.EVT_ERASE_BACKGROUND,self._onEraseBackground) self.Bind(wx.EVT_PAINT,self._onPaint) self._mouseIn = self._mouseDown = False def _onMouseEnter(self, event): self._mouseIn = True def _onMouseLeave(self, event): self._mouseIn = False def _onMouseDown(self, event): self._mouseDown = True def _onMouseUp(self, event): self._mouseDown = False self.sendButtonEvent() def sendButtonEvent(self): event = wx.CommandEvent(wx.wxEVT_COMMAND_BUTTON_CLICKED, self.GetId()) event.SetInt(0) event.SetEventObject(self) self.GetEventHandler().ProcessEvent(event) def _onEraseBackground(self,event): # reduce flicker pass def _onPaint(self, event): dc = wx.BufferedPaintDC(self) dc.SetFont(self.GetFont()) dc.SetBackground(wx.Brush(self.GetBackgroundColour())) dc.Clear() dc.DrawBitmap(self.Norm_bmp) # draw whatever you want to draw # draw glossy bitmaps e.g. dc.DrawBitmap if self._mouseIn: # If the Mouse is over the button dc.DrawBitmap(self, self.Mouse_over_bmp, self.Pos_bmp, useMask=False) if self._mouseDown: # If the Mouse clicks the button dc.DrawBitmap(self, self.Push_bmp, self.Pos_bmp, useMask=False)

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  • Hot to get custom http-header in asp.net?

    - by Sirius Lampochkin
    I have an asp.net appliction on the one server. There I've added code on server-side in Page_Load: Response.AddHeader("key", "password-key-from-hotel"); On the client side I have a form: $lt;form ... action="www.link-to-another-domaint" >   <input type="hidden" id="asd" value="fgh" > .... </form> <script type="text/javascript">   document.forms[0].submit(); </script> Then on the other domain - there is also my other application - I'm trying to get the hedaer "key" by this code: Request.Headers["key"].ToString(); But there is no such header. Is there is a desicion? Where is my mistake?

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  • Can't access resource from Generic.xaml within the Custom Control constructor.

    - by myermian
    I'm not sure why this is doing this, but I can't access the resource from within my constructor. XTabItem.cs using System; using System.ComponentModel; using System.Windows; using System.Windows.Controls; using System.Windows.Media; namespace MyStuff { public class XTabItem : TabItem { public static readonly DependencyProperty XTabItemNormalBackgroundProperty; /// <summary> /// Visual Property: Normal Background /// </summary> [Description("Determines the visibility of the close button."), Category("XTabItem Visual")] public Brush XTabItemNormalBackground { get { return (Brush)GetValue(XTabItemNormalBackgroundProperty); } set { SetValue(XTabItemNormalBackgroundProperty, value); } } static XTabItem() { DefaultStyleKeyProperty.OverrideMetadata(typeof(XTabItem), new FrameworkPropertyMetadata(typeof(XTabItem))); XTabItemNormalBackgroundProperty = DependencyProperty.Register("XTabItemNormalBackground", typeof(Brush), typeof(XTabItem), new UIPropertyMetadata(null)); } public XTabItem() { //XTabItemNormalBackground = (Brush)this.TryFindResource("XTabItemNormalBackgroundBrush"); //THIS DOES NOT WORK?? } public override void OnApplyTemplate() { base.OnApplyTemplate(); } } } Generic.xaml <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:MyStuff" xmlns:con="clr-namespace:MyStuff.Converters" > <SolidColorBrush x:Key="XTabItemNormalBackgroundBrush" Color="BlueViolet" /> <Style TargetType="{x:Type local:XTabItem}"> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type local:XTabItem}"> <!-- CONTENT TEMPLATE --> <Grid SnapsToDevicePixels="True"> <Border x:Name="_Border" Background="{Binding Path=XTabItemNormalBackground, RelativeSource={RelativeSource Mode=TemplatedParent}}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="1,1,1,0"> ... </Border> </Grid> </Style> </ResourceDictionary>

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  • Writing a custom auth system (like the default django auth system), use it to generate tables in DB

    - by dotty
    Hay all, I've been reading up on middleware and how to use it with a context object. I want to write a simple middleware class which i can use on my own applications, it will essentially be a cut down version of the django one. The problem i seem to have is that if i have INSTALLED_APPS = ('django.contrib.my_auth') in the settings file, all is well. I've also added MIDDLEWARE_CLASSES = ('django.contrib.my_auth.middleware.MyAuthMiddleware') in it and everything is fine. My question is, how would i make my middleware automatically generate tables from a models.py module, much like how the django auth does when i run manage.py syncdb? thanks

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  • Custom Terms of Use Page before login to SharePoint.

    - by Krish
    Hello I am using MOSS with ADS. I want to display Terms of Use page before the user can login into SharePoint with two button i.e. "Accept","Decline". If user select "Accept" he will be directed to sharepoint site, if not to our companies intranet front page. This will be applicable for the current session. ie. If the user has signed off, then it should prompt the terms of use again when user hits the MOSS site but once accepted user should not get this page again until he/she signs off. Please advise. Thank you

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  • Flex - Why is my custom event not being registered with the following event listener?

    - by flexfanatic
    printableInvoice.addEventListener(batchGenerated, printableInvoice_batchGeneratedHandler); Results in this error: 1120: Access of undefined property batchGenerated. I have tried it as FlexEvent.batchGenerated and FlashEvent.batchGenerated. The MetaData and function that dispatches the even in the component printableInvoice is all right. It I instantiate printableInvoice as an mxml component instead of via action-script it well let put a tag into the mxml line: batchGenerated="someFunction()" Thanks.

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  • How could i avoid the SAVE dialog in my custom blackberry Application?

    - by SIA
    Hi Everybody, I am writing a blackberry application and pushing screens one after another(three in series) Screen1 displays Screen2 and Screen2 displays Screen3 When i press "Back Key" on my Blackberry Device i.e., bold 9700, its prompts a dialog box with Question mark image and buttons "Save" "Discard" "Cancel". Why does this dialog appears? How can i avoid this dialog? Please Help Thanks SIA

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  • How to Access a Button present inside a Custom Control, from the implementing page?

    - by Subhen
    Hi, I have my generic.xaml containing the following code: <ControlTemplate TargetType="local:customVideoControl"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="600"/> <RowDefinition Height="200"/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width="200"/> <ColumnDefinition Width="200"/> <ColumnDefinition Width="200"/> </Grid.ColumnDefinitions> <MediaElement x:Name="customMediaPlayer" Source="{TemplateBinding CustomMediaSource}" HorizontalAlignment="Center" VerticalAlignment="Center" Height="{TemplateBinding Height}" Width="{TemplateBinding Width}" Grid.Row="0" Grid.ColumnSpan="3" /> <ToggleButton x:Name="playPauseBtn" Height="50" Width="50" Content="Pause" Grid.Row="1" Grid.Column="0"/> <Button x:Name="prevBtn" Height="50" Width="50" Content="Prev" Grid.Row="1" Grid.Column="1"/> <Button x:Name="nextBtn" Height="50" Width="50" Content="Next" Grid.Row="1" Grid.Column="2"/> </Grid> </ControlTemplate> Now on applyTemplate , I am accessing the controls like below: public override void OnApplyTemplate() { base.OnApplyTemplate(); ToggleButton playPauseBtn = GetTemplateChild("playPauseBtn") as ToggleButton; Button prevBtn= GetTemplateChild("prevBtn") as Button; Button nextBtn = GetTemplateChild("nextBtn") as Button; MediaElement customMediaPlayer = GetTemplateChild("customMediaPlayer") as MediaElement; playPauseBtn.Checked += (obj, Args) => { customMediaPlayer.Pause(); playPauseBtn.Content = "Play"; }; playPauseBtn.Unchecked += (obj, Args) => { customMediaPlayer.Play(); playPauseBtn.Content = "Pause"; }; nextBtn.Click += (obj, Args) => { customMediaPlayer.Source=new Uri(CustomMediaSource.ToString(),UriKind.RelativeOrAbsolute); }; prevBtn.Click += (obj, Args) => { customMediaPlayer.Source = new Uri(CustomMediaSource.ToString(), UriKind.RelativeOrAbsolute); }; } Now I want acccess the nextBtn, in the page where I am implementing like CustomVideoControl myVControl=new CustomVideoControl(); This will create the instance of the control, but I want to do something on the click of next and previous button, thta is present inside the CustomVideoControl in generic.xaml. Any help will be greatly appreciated. Thanks, Subhen

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  • how to associate a custom Page with new doccument in doccument library,also the fields in rhe page w

    - by Ankur Madaan
    Hey, I am onto a task in which i have to create a link in a doccument library either upload or new link,clicking on which a form/page "not infopath" will get open and allow to upload the doccument and along with that we have some text boxes on the same page which will be asking for the properties of the doccument(like "Customer of the doccument","content Developer") and after filling up all of the things when user click on submit than in the doccument library the value of the url as well as properties comes into the columns/fields of the doccument library. Can anyone have the solution for this?

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  • .NET-MVC Modelbinder not binding because of primary key, all other fields are right. What's happenin

    - by ropstah
    I want to perform an Add object scenario in .NET using the modelbinder. Function AddObject() As ActionResult Return View() End Function <AcceptVerbs(HttpVerbs.Post)> _ Function AddObject(<Bind(Exclude:="ObjectId")> ByVal o As BLL.Object) As ActionResult o.Save() End Function However, I get an error: 'o.ObjectId' is not declared or the module containing it is not loaded in the debugging session. While inspecting the object, all other fields are set properly. I've tried all combinations regarding: with/without Html.Hidden("ObjectId") to with/without <Bind(Exclude:="ObjectId")> and even setting o.ObjectId to Nothing, all with the same results. What am I doing wrong?

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  • Trying to run a codeigniter app on custom php

    - by hamstar
    I have a CodeIgniter app that I deployed to a server with php 5.2 and my dev box has 5.3, and some stuff doesn't work anymore. I didn't want to upgrade php and risk the other app on the server having issues. Anyway I compiled a custom PHP and added the following to a single .conf file in /etc/httpd/conf.d/zcid.conf with all the other conf files. <VirtualHost *:80> DocumentRoot /var/www/cid/app ServerName sub.example.co.nz </VirtualHost> <Directory "/var/www/cid/app"> authtype Basic authname "oh dear how did this get here i am no good with computer" authuserfile /path/to/auth require valid-user RewriteEngine on RewriteCond $1 !^(index\.php|robots\.txt|createEvent\.php|/cgi-bin) RewriteRule ^(.*)$ /index.php/$1 [L] AddHandler custom-php .php Action custom-php /cgi-bin/php53.cgi </Directory> In /var/www/cid/app I have the cgi-bin folder and the php53.cgi that I copied from /usr/local/php53/bin/php-cgi But now when I navigate to the subdomain it says: The requested URL /cgi-bin/php53.cgi/index.php/ was not found on this server. And if I try to browse to /cgi-bin it says (what it is supposed to?): You don't have permission to access /cgi-bin/ on this server. Quite confused now. Anyone know what to do here? Thanks :)

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  • CloudFront with Custom Origin and ELB

    - by kmfk
    We are using CloudFront for our static assets but also wanted to allow for Gzip. We set up a new distribution with a custom origin pointing back to our application servers which are behind a elastic load balancer. We manually keep the files in sync across the cluster and update them when we publish. However, with this set up, we get nothing but Miss and RefreshHits from CloudFront, which so far has defeated the purpose. Is there any additional settings in order to use an ELB as your custom origin? In the docs, it references this as a viable solution. It appears when we point the distribution to a single server in our production cluster, cloudfront properly caches our assets. Is it possible that the sticky sessions cookie and the subsequent header that gets added by it could be an issue? Cache-Control: no-cache="set-cookie" //Added by load balancer Any ideas? FYI - currently, we have our custom origin pointing to a single EC2 instance, so caching is working correctly - in case you try to curl the file below. Example headers: curl -I http://static.quick-cdn.com/css/9850999.css HTTP/1.0 200 OK Accept-Ranges: bytes Cache-Control: max-age=3700 Cache-Control: no-cache="set-cookie" Content-Length: 23038 Content-Type: text/css Date: Thu, 12 Apr 2012 23:03:52 GMT Last-Modified: Thu, 12 Apr 2012 23:00:14 GMT Server: Apache/2.2.17 (Ubuntu) Vary: Accept-Encoding X-Cache: RefreshHit from cloudfront X-Amz-Cf-Id: K_q7Zy3_jdzlEJ85ukELVtdx1GmuXqApAbZZ7G0fPt0mxRMqPKX5pQ==,RzJmPku-rEIO9WlvuSoKa8hiAaR3dLk5KC4cQMWWrf_MDhmjWe8n6A== Via: 1.0 28c34f9fbf559a21ee16594849e4fc9c.cloudfront.net (CloudFront) Connection: close

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  • MS Word custom dictionary making spellcheck slow - ideas?

    - by ezuk
    I have a user who edits technical materials. She uses MS Word's Custom Dictionary all the time for spelling; it has grown very large, and is now making spell check very slow. All of the advice I've read online says to disable the custom dictionary. This is an easy solution, but is not workable for the user, because she actually needs this dictionary. So, is there any way to optimize the custom dictionary and/or Word itself, so that a large dictionary file doesn't slow things down quite so badly? Many thanks. Update after suggestions: I ran contig on the file, and it reports just 1 frag, so that's not the issue I think. The file is 9.95KB -- 1,117 lines, each consisting of just a single word. I viewed the file using Notepad and none of the lines seems corrupted, strange, or overly long (no line seems to be over 10 chars or so). Both of your suggestions were helpful so I will upvote both; any further tips would be most welcome.

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  • How to make quicksilver remember custom trigger

    - by corroded
    I am trying to make a custom trigger for my shell/apple script file to run so I can just launch my dev environment at the push of a button. So basically: I have a shell script(and some apple script included) in ~ named start_server.sh which does 3 things: start up solr server start up memcached start up script/server I have a saved quicksilver command(.qs) that opens up start_server.sh(so start_server.sh, then the action is "Run in Terminal") I created a custom trigger that calls this saved qs command. I did that then tested it and it works. I then tried to double check it so I quit quicksilver and when I checked the triggers it just said: "Open (null)" as the action. I set the trigger again and when i restarted QS the same thing happened again. I don't know why but my old custom trigger to open terminal has worked since forever so why doesn't this one work? Here's a screenie of the triggers after I restart QS: http://grab.by/4XWW If you have any other suggestion on how to make a "push button" start for my server then please do so :) Thanks! As an added note, I have already tried the steps on this thread but to no avail: http://groups.google.com/group/blacktree-quicksilver/browse_thread/thread/7b65ecf6625f8989

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  • Can google “see” this custom javascript code which displays links from an external site to mine

    - by webmasters
    I have a javascript code on my site who displays links from another site. This is what I have on my source before: <script language="JavaScript" type="text/javascript">showLink(1);</script> This is what I have copied from my source after the page has loaded: <script language="JavaScript" type="text/javascript">showLink(1);</script><a rel="nofollow" target="_blank" class="anc" href="http://x5.external_site.net/sc/out.php?s=5483&amp;o=http%3A%2F%2Fwww.bluetooth.com">Bluetooth Devices</a> Can google see this link?

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  • jQuery Ajax Error Handling – How To Show Custom Error Messages

    - by schnieds
    So you want to make your error feedback nice for your users…Kind of an ironic statement isn’t it? We obviously want to avoid errors if at all possible in our applications, but when errors do occur then we want to provide some nice feedback to our users. The worst thing that can happen is to blow up a huge server exception page when something goes wrong or equally bad is not providing any feedback at all and leaving the user in the dark. Although I do not recommend displaying actual .NET Framework exception messages or stack traces to the user in most instances; they are usually not helpful to the user and can be a security concern.... [Read More]Aaron Schniederhttp://www.churchofficeonline.com

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  • Access UIButton's titleLabel with custom background image

    - by Meltemi
    Quick one: I have a custom button image that I want to use but I still want to change the text of the button with setTitle:forState:. When I use a "custom" button in IB I lose the Title view. When I use Rounded Rect in IB the custom image appears scrunched w/in the Rounded Rect button. Why is this so difficult?

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  • Prevent Custom Entity being deleted from Entity Framework during Update Model Wizard

    - by rbg
    In Entity Framework v1 If you create a Custom Entity to map it to a Stored Procedure during FunctionImport and then Select "Update Model from Database" the Update Model Wizard removes the Custom Entity (as added Manually in the SSDL XML prior to functionImport) from the SSDL. Does anyone know if this limitation has been dealt with Entity Framework v4? I mean is there a way to prevent the Wizard from removing the Custom Entity from the Storage Schema (SSDL) during Model Update from Database????

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  • Knockoutjs - stringify to handling observables and custom events

    - by Renso
    Goal: Once you viewmodel has been built and populated with data, at some point it goal of it all is to persist the data to the database (or some other media). Regardless of where you want to save it, your client-side viewmodel needs to be converted to a JSON string and sent back to the server. Environment considerations: jQuery 1.4.3+ Knockoutjs version 1.1.2   How to: So let’s set the stage, you are using Knockoutjs and you have a viewmodel with some Knockout dependencies. You want to make sure it is in the proper JSON format and via ajax post it to the server for persistence.   First order of business is to deal with the viewmodel (JSON) object. To most the JSON stringifier sounds familiar. The JSON stringifier converts JavaScript data structures into JSON text. JSON does not support cyclic data structures, so be careful to not give cyclical structures to the JSON stringifier. You may ask, is this the best way to do it? What about those observables and other Knockout properties that I don’t want to persist or want their actual value persisted and not their function, etc. Not sure if you were aware, but KO already has a method; ko.utils.stringifyJson() - it's mostly just a wrapper around JSON.stringify. (which is native in some browsers, and can be made available by referencing json2.js in others). What does it do that the regular stringify does not is that it automatically converts observable, dependentObservable, or observableArray to their underlying value to JSON. Hold on! There is a new feature in this version of Knockout, the ko.toJSON. It is part of the core library and it will clone the view model’s object graph, so you don’t mess it up after you have stringified  it and unwrap all its observables. It's smart enough to avoid reference cycles. Since you are using the MVVM pattern it would assume you are not trying to reference DOM nodes from your view. Wait a minute. I can already see this info on the http://knockoutjs.com/examples/contactsEditor.html website, why mention it all here? First of this is a much nicer blog, no orange ? At this time, you may want to have a look at the blog and see what I am talking about. See the save event, how they stringify the view model’s contacts only? That’s cool but what if your view model is a representation of your object you want to persist, meaning it has no property that represents the json object you want to persist, it is the view model itself. The example in http://knockoutjs.com/examples/contactsEditor.html assumes you have a list of contacts you may want to persist. In the example here, you want to persist the view model itself. The viewmodel here looks something like this:     var myViewmodel = {         accountName: ko.observable(""),         accountType: ko.observable("Active")     };     myViewmodel.isItActive = ko.dependentObservable(function () {         return myViewmodel.accountType() == "Active";     });     myViewmodel.clickToSaveMe = function() {         SaveTheAccount();     }; Here is the function in charge of saving the account: Function SaveTheAccount() {     $.ajax({         data: ko.toJSON(viewmodel),         url: $('#ajaxSaveAccountUrl').val(),         type: "POST",         dataType: "json",         async: false,         success: function (result) {             if (result && result.Success == true) {                 $('#accountMessage').html('<span class="fadeMyContainerSlowly">The account has been saved</span>').show();                 FadeContainerAwaySlowly();             }         },         error: function (xmlHttpRequest, textStatus, errorThrown) {             alert('An error occurred: ' + errorThrown);         }     }); //ajax }; Try run this and your browser will eventually freeze up or crash. Firebug will tell you that you have a repetitive call to the first function call in your model that keeps firing infinitely.  What is happening is that Knockout serializes the view model to a JSON string by traversing the object graph and firing off the functions, again-and-again. Not sure why it does that, but it does. So what is the work around: Nullify your function calls and then post it:         var lightweightModel = viewmodel.clickToSaveMe = null;         data: ko.toJSON(lightweightModel), So then I traced the JSON string on the server and found it having issues with primitive types. C#, by the way. So I changed ko.toJSON(model) to ko.toJS(model), and that solved my problem. Of course you could just create a property on the viewmodel for the account itself, so you only have to serialize the property and not the entire viewmodel. If that is an option then that would be the way to go. If your view model contains other properties in the view model that you also want to post then that would not be an option and then you’ll know what to watch out for. Hope this helps.

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  • Professional Custom Logo Design vs. Mr. Right

    John is an ex-marine and ex-employee of general motors. He recently lost his job working as a welder on the assembly lines of one of GM manufacturing plants. John has traveled a lot and knows a lot a... [Author: Emily Matthew - Web Design and Development - March 31, 2010]

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  • How to use Blazeds with a custom classloader?

    - by festerwim
    Hi, has anybody tried using a custom classloader with BlazeDS? We have a web application using BlazeDS and we can convert Java objects in to ActionScript object and back without problems in the main application. However, we also have a plug-in mechanism based on a custom classloader. BlazeDS cannot map the types contained in jar files of that custom classloader since I don't know how to tell it to BlazeDS. Has anybody already done this? The livedocs of TypeMarshallingcontext show a setClassloader() method, but since the context seems to be a singleton, I assume this will not work if you have multiple custom classloaders (we have 1 for each plugin that is deployed) regards, Wim

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  • Custom UIView built with Interface Builder accessible/positionable via Interface Builder

    - by Nader
    This shouldn't be this confusing. I have a custom UIView with a bunch on controls on it. UILabels, buttons, etc. I've created this Nib using Interface Builder. I want to be able to position this custom uiview on another UIView using the interface builder. How do I link my UIView custom class, to the nib? initWithCoder gets called, but I want this class to get loaded from the nib. Thanks

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  • Using NServiceBus behind a custom web service

    - by Michael Stephenson
    In this post I'd like to talk about an architecture scenario we had recently and how we were able to utilise NServiceBus to help us address this problem. Scenario Cognos is a reporting system used by one of my clients. A while back we developed a web service façade to allow line of business applications to be able to access reports from Cognos to support their various functions. The service was intended to provide access to reports which were quick running reports or pre-generated reports which could be accessed real-time on demand. One of the key aims of the web service was to provide a simple generic interface to allow applications to get any report without needing to worry about the complex .net SDK for Cognos. The web service also supported multi-hop kerberos delegation so that report data could be accesses under the context of the end user. This service was working well for a period of time. The Problem The problem we encountered was that reports were now also required to be available to batch processes. The original design was optimised for low latency so users would enjoy a positive experience, however when the batch processes started to request 250+ concurrent reports over an extended period of time you can begin to imagine the sorts of problems that come into play. The key problems this new scenario caused are: Users may be affected and the latency of on demand reports was significantly slower The Cognos infrastructure was not scaled sufficiently to be able to cope with these long peaks of load From a cost perspective it just isn't feasible to scale the Cognos infrastructure to be able to handle the load when it is only for a couple of hour window each night. We really needed to introduce a second pattern for accessing this service which would support high through-put scenarios. We also had little control over the batch process in terms of being able to throttle its load. We could however make some changes to the way it accessed the reports. The Approach My idea was to introduce a throttling mechanism between the Web Service Façade and Cognos. This would allow the batch processes to push reports requests hard at the web service which we were confident the web service can handle. The web service would then queue these requests and process them behind the scenes and make a call back to the batch application to provide the report once it had been accessed. In terms of technology we had some limitations because we were not able to use WCF or IIS7 where the MSMQ-Activated WCF services could have helped, but we did have MSMQ as an option and I thought NServiceBus could do just the job to help us here. The flow of how this would work was as follows: The batch applications would send a request for a report to the web service The web service uses NServiceBus to send the message to a Queue The NServiceBus Generic Host is running as a windows service with a message handler which subscribes to these messages The message handler gets the message, accesses the report from Cognos The message handler calls back to the original batch application, this is decoupled because the calling application provides a call back url The report gets into the batch application and is processed as normal This approach looks something like the below diagram: The key points are an application wanting to take advantage of the batch driven reports needs to do the following: Implement our call back contract Make a call to the service providing a call back url Provide a correlation ID so it knows how to tie each response back to its request What does NServiceBus offer in this solution So this scenario is not the typical messaging service bus type of solution people implement with NServiceBus, but it did offer the following: Simplified interaction with MSMQ Offered the ability to configure the number of processes working through the queue so we could find a balance between load on Cognos versus the applications end to end processing time NServiceBus offers retries and a way to manage failed messages NServiceBus offers a high availability setup The simple thing is that NServiceBus gave us the platform to build the solution on. We just implemented a message handler which functionally processed a message and we could rely on NServiceBus to do all of the hard work around managing the queues and all of the lower level things that would have took ages to write to any kind of robust level. Conclusion With this approach we were able to deal with a fairly significant performance issue with out too much rework. Hopefully this write up gives people some insight into ideas on how to leverage the excellent NServiceBus framework to help solve integration and high through-put scenarios.

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