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  • Jquery tabs and IE8

    - by Stephen
    hi, i am using jquery to create the following using this code $(document).ready(function() { $("#content").tabs({ fx: { opacity: 'toggle' } }); }); $(document).ready(function() { $("#documents").tabs({ fx: { opacity: 'toggle' } }); }); Here it is in firefox working like in every other browser like this: https://www.completelettingsolutions.co.uk/working.JPG but in IE 8 ... it does this but in 7 its fine. (remove the 1 at the start of the link) 1https://www.completelettingsolutions.co.uk/notWorking.JPG I think it is somethin to do with the script opacity but i cant get it to work. does any one have any idea. Cheers

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  • in php, how to send the html tag to mail

    - by zahir hussain
    <script type="text/javascript"> var head= 23; </script> <?php $h="<script language='javascript'> document.write(head);</script>"; $headers = "MIME-Version: 1.0" . "\r\n"; $headers .= "Content-type:text/html;charset=ISO-8859-1" . "\r\n"; $mail_from='[email protected]'; $name="husssain"; $headers.="From: $name <$mail_from>"; $con="Welcome to world"; $to ="[email protected]"; $send_contact = mail($to,$con,$h,$headers); ?> then i send the $h to my mail id but i recieve only this <script language='javascript'> document.write(head);</script>

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  • How to trigger saved password autofill in browsers?

    - by Aleksander Kmetec
    I have a web application written in pure JavaScript (no pre-generated HTML except for the document which loads all the JS files). This app contains a login form which is created dynamically when the document.ready event event is triggered. I trick the browser into displaying the "Remember password?" dialog by posting the login form into a hidden iframe before logging in using ajax (in Firefox the password appears on the saved password list, so this part obviously works) but saved passwords never get filled in after the login screen is loaded again at a later time. The same thing happens in Firefox and Safari. Is there something I can do or some function I can call to trigger autofill? UPDATE: autofill works in Safari on initial page load, but not when user logs out and the login form is recreated without a page reload. In Firefox it never works.

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  • ServerAlias www.example.com is not recognized

    - by Tianzhou Chen
    Below is my config file: NameVirtualHost 12.34.56.78:80 < VirtualHost 12.34.56.78:80 ServerAdmin [email protected] ServerName domain1.com ServerAlias www.domain1.com DocumentRoot /srv/www/domain1.com/public_html1/ ErrorLog /srv/www/domain1.com/logs/error.log CustomLog /srv/www/domain1.com/logs/access.log combined < /VirtualHost < VirtualHost 12.34.56.78:80 ServerAdmin [email protected] ServerName domain2.com ServerAlias www.domain2.com DocumentRoot /srv/www/domain2.com/public_html1/ ErrorLog /srv/www/domain2.com/logs/error.log CustomLog /srv/www/domain2.com/logs/access.log combined < /VirtualHost The thing is when I put www.domain1.com into browser, apache2 doesn't retrieve the web page resides in /srv/www/domain1.com/public_html1/, instead, it gets the page from the default document root defined in another file. However, if I put www.domain2.com, everything works fine. I don't see any difference between two VirtualHost config block, so I wonder what does make the difference. BTW, I haven't put any .htaccess file under their document root. Thanks for your advice! Tianzhou

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  • detachEvent not working with named inline functions

    - by Polshgiant
    I ran into a problem in IE8 today (Note that I only need to support IE) that I can't seem to explain: detachEvent wouldn't work when using a named anonymous function handler. document.getElementById('iframeid').attachEvent("onreadystatechange", function onIframeReadyStateChange() { if (event.srcElement.readyState != "complete") { return; } event.srcElement.detachEvent("onreadystatechange", onIframeReadyStateChange); // code here was running every time my iframe's readyState // changed to "complete" instead of only the first time }); I eventually figured out that changing onIframeReadyStateChange to use arguments.callee (which I normally avoid) instead solved the issue: document.getElementById('iframeid').attachEvent("onreadystatechange", function () { if (event.srcElement.readyState != "complete") { return; } event.srcElement.detachEvent("onreadystatechange", arguments.callee); // code here now runs only once no matter how many times the // iframe's readyState changes to "complete" }); What gives?! Shouldn't the first snippet work fine?

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  • vectorization of a text file

    - by Fox
    I am trying to implement vectorization of a text file...I have created a dictionary (Unique words in all the documents) ... Which is the best way to implement this in java? For example - My dictionary has the following words - {w1, w2, w3, w4} And I have 2 documents each having subset of the words in the vocabulary. I need to write to a text file the matrix in the form -- 1,3,4,0 0,0,2,1 Here each row represents a document and the values represent the occurrence of each word in the document. Can you suggest me the most efficient way to implement this in Java?

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  • Printing an NSDocument

    - by Brian Postow
    I'm trying to print a document. The document is an array of NSImageReps, or a single NSPDFImageRep, which has multiple pages. I'm having trouble figuring out how to use the NSPrintOperation class to print this. The NSPrintOperation seems to need an NSView to print. Do I need to manually add each image into the view at a calculated position and then let it do the pagination? that seems like it isn't in the spirit of Cocoa... is there some technique that I'm missing?

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  • C# XMLSerializer fails with List<T>

    - by Redshirt
    Help... I'm using a singleton class to save all my settings info. It's first utilized by calling Settings.ValidateSettings(@"C:\MyApp") The problem I'm having is that 'List Contacts' is causing the xmlserializer to fail to write the settings file, or to load said settings. If I comment out the List then I have no problems saving/loading the xml file. What am I doing wrong... Thanks in advance // The actual settings to save public class MyAppSettings { public bool FirstLoad { get; set; } public string VehicleFolderName { get; set; } public string ContactFolderName { get; set; } public List<ContactInfo> Contacts { get { if (contacts == null) contacts = new List<ContactInfo>(); return contacts; } set { contacts = value; } } private List<ContactInfo> contacts; } // The class in which the settings are manipulated public static class Settings { public static string SettingPath; private static MyAppSettings instance; public static MyAppSettings Instance { get { if (instance == null) instance = new MyAppSettings(); return instance; } set { instance = value; } } public static void InitializeSettings(string path) { SettingPath = Path.GetFullPath(path + "\\MyApp.xml"); if (File.Exists(SettingPath)) { LoadSettings(); } else { Instance.FirstLoad = true; Instance.VehicleFolderName = "Cars"; Instance.ContactFolderName = "Contacts"; SaveSettingsFile(); } } // load the settings from the xml file private static void LoadSettings() { XmlSerializer ser = new XmlSerializer(typeof(MyAppSettings)); TextReader reader = new StreamReader(SettingPath); Instance = (MyAppSettings)ser.Deserialize(reader); reader.Close(); } // Save the settings to the xml file public static void SaveSettingsFile() { XmlSerializer ser = new XmlSerializer(typeof(MyAppSettings)); TextWriter writer = new StreamWriter(SettingPath); ser.Serialize(writer, Settings.Instance); writer.Close(); } public static bool ValidateSettings(string initialFolder) { try { Settings.InitializeSettings(initialFolder); } catch (Exception e) { return false; } // Do some validation logic here return true; } } // A utility class to contain each contact detail public class ContactInfo { public string ContactID; public string Name; public string PhoneNumber; public string Details; public bool Active; public int SortOrder; } }

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  • Setting different default applications for different Desktop Environment

    - by Anwar
    I am using Ubuntu 12.04 with default Unity interface. I installed later the KDE desktop, XFCE, LXDE, gnome-shell and Cinnamon. The KDE comes with different default applications than Unity, such as kwrite for text editing, konsole as virtual terminal, kfontview for font viewing and installing, dolphin as File browser etc. Other DE come with some other default applications. The problem arises when you want to open a file such as a text file, with which can both be opened by gedit and kwrite, I want to use kwrite on KDE and gedit on Unity or Gnome. But, there is no way to set like this. I can set default application for text file by changing respective settings in both KDE and Unity, but It become default for both DE. For example, If I set kfontviewer as default font viewing application in KDE, it also opens fonts when I am in Unity or Gnome and vice versa. This is a problem because, loading other DE's program takes long time than the default one for the used DE. My question is: Can I use different default applications for different DE? How?

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  • Working with Key Flex Fields in OAF

    - by PRajkumar
    1. Create a New Workspace and Project Right click Workspaces and click create New OA Workspace and name it as PRajkumarKFFDemo. Automatically a new OA Project will also be created. Name the project as KFFDemo and package as prajkumar.oracle.apps.fnd.kffdemo   2. Create a New Application Module (AM) Right Click on KFFDemo > New > ADF Business Components > Application Module Name -- KFFAM Package -- prajkumar.oracle.apps.fnd.kffdemo.server   Check Application Module Class: KFFAMImpl Generate JavaFile(s)   3. Create a New View Object (VO) Right click on KFFDemo > New > ADF Business Components > View Object Name -- KFFVO Package -- prajkumar.oracle.apps.fnd.kffdemo.server   Note - The VO is not based on any EO so click next and go to the query section and paste the query   SELECT  code_combination_id FROM    gl_code_combinations_kfv   In Step8 Check Object Class: KFFVOImpl -> Generate Java File -> Bind Variable Accessors   4. Add View Object to Root UI Application Module Right Click on KFFAM > Edit KFFAM > Data Model and shuttle KFFVO from Available View Objects to Data Model   5. Create a New Page Right click on KFFDemo > New > Web Tier > OA Components > Page Name -- KFFPG Package -- prajkumar.oracle.apps.fnd.kffdemo.webui   6. Select the KFFPG and go to the strcuture pane where a default region has been created   7. Select region1 and set the following properties:   Attribute Property ID PageLayoutRN AM Definition prajkumar.oracle.apps.fnd.kffdemo.server.KFFAM Window Title Key Flex Field Demo Window Title Key Flex Field Demo     8. Create Stack Layout Region Under Page Layout Region Right click PageLayoutRN > New > Region   Attribute Property ID MainRN AM Definition stackLayout   9. Create a New Item of type Flex under the Stack Layout Region Right click on MainRN > New > Item Set Following Properties for New Item --   Attribute Property ID KeyFlexItem Item Style Flex Prompt Accounting Key Flex Field Appl Short Name SQLGL Name GL# Type Key View Instance KFFVO1     10. Create Controller for page KFFPG Right Click on PageLayoutRN > Set New Controller Package Name: prajkumar.oracle.apps.fnd.kffdemo.webui Class Name: KFFCO   Write Following Code in KFFCO processRequest   public void processRequest(OAPageContext pageContext, OAWebBean webBean) {  super.processRequest(pageContext, webBean);    OAKeyFlexBean kffId = (OAKeyFlexBean)webBean.findIndexedChildRecursive("KeyFlexItem");    // Set the code combination lov   kffId.useCodeCombinationLOV(true);   //set the structure code for the item key flex    kffId.setStructureCode("FED_AFF");   //Set the attribute name to the item   kffId.setCCIDAttributeName("CodeCombinationId");  //Execute the Query   KFFAMImpl am = (KFFAMImpl)pageContext.getApplicationModule(webBean);   KFFVOImpl vo = (KFFVOImpl)am.findViewObject("KFFVO1");          if(!vo.isPreparedForExecution())   {          vo.executeQuery();   } }   Note -- If you do not want to see the key flex field is merging one then change the code in the controller class as below   kffId.useCodeCombinationLOV(false);   11. Use the below Query to find the Structure Code   SELECT  fif.application_id,                  fif.id_flex_code,                  fif.id_flex_name,                  fif.application_table_name,                   fif.description,                  fifs.id_flex_num,                  fifs.id_flex_structure_code,                  fifse.segment_name,                  fifse.segment_num,                  fifse.flex_value_set_id  FROM     fnd_id_flexs                    fif,                  fnd_id_flex_structures   fifs,                   fnd_id_flex_segments    fifse  WHERE  fif.application_id      = fifs.application_id  AND       fif.id_flex_code         = fifs.id_flex_code  AND       fifse.application_id   = fif.application_id  AND       fifse.id_flex_code      = fif.id_flex_code  AND       fifse.id_flex_num      = fifs.id_flex_num  AND       fif.id_flex_code         LIKE 'GL#' AND       fif.id_flex_name       LIKE 'Accounting Flexfield';   12. Congratulation you have successfully finished. Run Your page and Test Your Work        

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  • How to balance a non-symmetric "extension" based game?

    - by Klaim
    Most strategy games have fixed units and possible behaviours. However, think of a game like Magic The Gathering : each card is a set of rules. Regularly, new sets of card types are created. I remember that the firsts editions of the game have been said to be prohibited in official tournaments because the cards were often too powerful. Later extensions of the game provided more subtle effects/rules in cards and they managed to balance the game apparently effectively, even if there is thousands of different cards possible. I'm working on a strategy game that is a bit in the same position : every units are provided by extensions and the game is thought to be extended for some years, at least. The effects variety of the units are very large even with some basic design limitations set to be sure it's manageable. Each player choose a set of units to play with (defining their global strategy) before playing (like chooseing a themed deck of Magic cards). As it's a strategy game (you can think of Magic as a strategy game too in some POV), it's essentially skirmish based so the game have to be fair, even if the players don't choose the same units before starting to play. So, how do you proceed to balance this type of non-symmetric (strategy) game when you know it will always be extended? For the moment, I'm trying to apply those rules but I'm not sure it's right because I don't have enough design experience to know : each unit would provide one unique effect; each unit should have an opposite unit that have an opposite effect that would cancel each others; some limitations based on the gameplay; try to get a lot of beta tests before each extension release? Looks like I'm in the most complex case?

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  • Retrieving of coordinates from google maps and search

    - by cheesebunz
    I know there is a way to retrieve the coordinates by clicking on the map, using specifically document.getElementById("lonTb").value=point.x; document.getElementById("latTb").value=point.y; Firstly, i have a html file namely MapToolKit.html, a mapGPS.js and a mapSearch.js. how do i input the coordinates returns into the js? I just need to be able to click the map for coordinates, not neccessary the search returns. Here's the file which i uploaded. http://www.mediafire.com/?0minqxgwzmx

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  • How to disable an ASP.NET linkbutton when clicked

    - by Jeff Widmer
    Scenario: User clicks a LinkButton in your ASP.NET page and you want to disable it immediately using javascript so that the user cannot accidentally click it again.  I wrote about disabling a regular submit button here: How to disable an ASP.NET button when clicked.  But the method described in the other blog post does not work for disabling a LinkButton.  This is because the Post Back Event Reference is called using a snippet of javascript from within the href of the anchor tag: <a id="MyContrl_MyButton" href="javascript:__doPostBack('MyContrl$MyButton','')">My Button</a> If you try to add an onclick event to disable the button, even though the button will become disabled, the href will still be allowed to be clicked multiple times (causing duplicate form submissions).  To get around this, in addition to disabling the button in the onclick javascript, you can set the href to “#” to prevent it from doing anything on the page.  You can add this to the LinkButton from your code behind like this: MyButton.Attributes.Add("onclick", "this.href='#';this.disabled=true;" + Page.ClientScript.GetPostBackEventReference(MyButton, "").ToString()); This code adds javascript to set the href to “#” and then disable the button in the onclick event of the LinkButton by appending to the Attributes collection of the ASP.NET LinkButton control.  Then the Post Back Event Reference for the button is called right after disabling the button.  Make sure you add the Post Back Event Reference to the onclick because now that you are changing the anchor href, the button still needs to perform the original postback. With the code above now the button onclick event will look something like this: onclick="this.href='#';this.disabled=true;__doPostBack('MyContrl$MyButton','');" The anchor href is set to “#”, the linkbutton is disabled, AND then the button post back method is called. Technorati Tags: ASP.NET LinkButton

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  • Greiner-Hormann clipping problem

    - by Belgin
    I have a set of planar polygons in 3D space defined by their vertices in counterclockwise order. Let's define the 'positive face' as being the face of the 3D polygon such as when observed, the vertices appear in counterclockwise order, and the 'negative face', the face which when observed, the vertices appear in clockwise order. I'm doing perspective projection of the set of polygons onto a projection polygon defined by the points in this order: (0, h, 0), (0, 0, 0), (w, 0, 0), and (w, h, 0), where w and h are strictly positive integers. The positive face of this projection polygon is oriented towards positive Z, and the camera point is somewhere at (0, 0, d), where d is a strictly negative number. In order to 'clip' the projected polygons into the projection polygon, I'm applying the Greiner-Hormann (PDF) clipping algorithm, which requires that the clipper and the to-be-clipped polygons be in the same order (i.e. clockwise or counterclockwise). My question is the following: How can I determine whether the projected face of the 3D polygon is the negative or the positive one? Meaning, how do I find out if I have to work with the vertices in normal or inverted order for the algorithm to work? I noticed that only if the 3D polygon is facing the projection polygon with its negative face, both of them are in the same order (counterclockwise), otherwise, a modification needs to be done. Here is a picture (PNG) that illustrates this. Note that the planes described by the polygon from the set and the projection polygon may not always be parallel.

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  • Rebinding jQuery qtip tooltip on images in bxcarousel

    - by skerit
    I'm using bxcarousel to show a bunch of images. Each image has a tooltip, which I display using qtip. This works fine for the first round, but when the images come round a second time the tooltips don't show anymore (because bxcarousel removes an element that slides out and puts it back at the end) An example of the carousel can be found here: http://www.kipdola.be/carousel/carousel.html This is the code used to bind the events (maybe it needs a "live" function somewhere?) // Create the tooltips only on document load $(document).ready(function() { // Use the each() method to gain access to each elements attributes $('#shopcarousel a[rel]').each(function() { $(this).qtip(

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  • Python IDLE: How to type correct indentation?

    - by user2988464
    Mac: Maverick Python: 3.4 I tried to testtimeit module in Python's IDLE import timeit >>> timeit.timeit( "obj.method", """ class SomeClass: def method(self): pass obj = SomeClass() """) When I tried to type def method(self): on the next line of class SomeClass, I hit Tab, it prompted a window showing the files inside my Document directory. So I hit Ctrl+Tab instead. But I still got the error: Traceback (most recent call last): File "<pyshell#26>", line 6, in <module> """) File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/timeit.py", line 213, in timeit return Timer(stmt, setup, timer).timeit(number) File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/timeit.py", line 122, in __init__ code = compile(src, dummy_src_name, "exec") File "<timeit-src>", line 9 _t0 = _timer() ^ IndentationError: unindent does not match any outer indentation level Can someone explain: how to fix it, and how to avoid the prompt of My Document appear? Thx!!!

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  • How to get value of a input field in Javascript

    - by gaurav.mishra280295
    I am using valums-file-uploader plugin. It allows me to upload files using ajax. I have a problem with it. I have the following script- <input type="text" id="Gaurav" name="Gaurav" /> <script src="fileuploader.js" type="text/javascript"></script> <script> function createUploader(){ var uploader = new qq.FileUploader({ element: document.getElementById('file'), action: 'do-nothing.php', params:{param: document.getElementById('Gaurav').value}, allowedExtensions: ['jpg', 'jpeg', 'png', 'gif'], minSizeLimit: 1, debug: false }); } // in your app create uploader as soon as the DOM is ready // dont wait for the window to load window.onload = createUploader; </script> In it, I want to set the value of param entered by the user. The code is working properly for default value of Gaurav, but didn't work for user inputted value.

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  • Design view disappeared from Interface Builder

    - by skywalker168
    All of a sudden, the visual design window disappeared from my Interface Builder. It is a regular UIView, has some UIImageView, UILabel, and UIButtons on it. When I open IB, I can see the document window (with File's Owner, First Responder and View in it), Library and Inspector, but the visual design window disappeared. Double click on "View" in the document window doesn't do anything. If I go to List mode, I can see all the components on the view, but just can no longer find the visual design window. All other XIB can open just fine, only this XIB lost its design window. First I thought maybe it was hidden somewhere on the screen. Tried all kinds of things, even rebooting the computer, but nothing helped. Can anyone help? Thanks in advance! By the way, I'm running SDK 3.2 Beta 3.

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  • Strict Pomodoro and other time management Chrome extensions

    - by kerry
    I have recently begun using the Pomodoro Technique to increase my productivity. However, I still find myself getting sucked in to the vortex of useless information that is the internet. With that in mind I began searching for a useful chrome extension to replace the Android Pomodoro app I have been using to manage my ‘doros. I even considered writing it myself. Luckily, I stumbled on one that had a similar featureset to what I was looking for. Strict Pomodoro is an excellent Chrome extension for practicing Pomodoro. Though lacking a few key features, such as the ability to set the duration of your pomodoros and breaks, it still has a key feature that helps me stay on task. It blocks time sucking websites. You can set filter lists and it will keep you from accessing them during a Pomodoro. Effectively reminding you to stay on task. Also, the author readily admits that it was quickly put together and new features may be added down the road. For now, it is still an excellent option. For those of you who do not practice Pomodoro but are trying to stay on task. The StayFocusd extension will effectively manage the amount of time you spend on useless (non-productive) sites. It also has a rich feature set that may be better for your work habits. OK, breaks over. Time to get back to work. 25 minutes at a time.

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  • C# Role Provider for multiple applications

    - by Juventus18
    I'm making a custom RoleProvider that I would like to use across multiple applications in the same application pool. For the administration of roles (create new role, add users to role, etc..) I would like to create a master application that I could login to and set the roles for each additional application. So for example, I might have AppA and AppB in my organization, and I need to make an application called AppRoleManager that can set roles for AppA and AppB. I am having troubles implementing my custom RoleProvider because it uses an initialize method that gets the application name from the config file, but I need the application name to be a variable (i.e. "AppA" or "AppB") and passed as a parameter. I thought about just implementing the required methods, and then also having additional methods that pass application name as a parameter, but that seems clunky. i.e. public override CreateRole(string roleName) { //uses the ApplicationName property of this, which is set in web.config //creates role in db } public CreateRole(string ApplicationName, string roleName) { //creates role in db with specified params. } Also, I would prefer if people were prevented from calling CreateRole(string roleName) because the current instance of the class might have a different applicationName value than intended (what should i do here? throw NotImplementedException?). I tried just writing the class without inheriting RoleProvider. But it is required by the framework. Any general ideas on how to structure this project? I was thinking make a wrapper class that uses the role provider, and explicitly sets the application name before (and after) and calls to the provider something like this: static class RoleProviderWrapper { public static CreateRole(string pApplicationName, string pRoleName) { Roles.Provider.ApplicationName = pApplicationName; Roles.Provider.CreateRole(pRoleName); Roles.Provider.ApplicationName = "Generic"; } } is this my best-bet?

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  • Cleanup for control inside a FlowDocument

    - by Thorarin
    I have a custom control that I use inside a FlowDocument. The control uses a System.Drawing.ImageAnimator to display transparent, animated GIF images. Why is this such a pain in the butt in WPF anyway? :P In my original implementation, this was causing memory leaks when a paragraph containing the control was being deleted from the document, because the ImageAnimator kept a reference to the control for event handling. I've now implemented a WeakEventManager pattern which seems to indeed fix the leak itself, but I would like to stop "OnFrameChanged" events from being fired if a particular animated GIF is not currently in the document, instead of relying on the garbage collector to eventually collect the control objects and my event manager to notice that there no longer are valid listeners to the event. Basically, I would like to take a more active role in this and have the control react to being removed from the FlowDocument. Is there some way to do this? I've been unable to find it. OnVisualParentChanged doesn't get fired, because the direct parent (a Paragraph) is unchanged.

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  • Is there a design pattern for chained observers?

    - by sharakan
    Several times, I've found myself in a situation where I want to add functionality to an existing Observer-Observable relationship. For example, let's say I have an Observable class called PriceFeed, instances of which are created by a variety of PriceSources. Observers on this are notified whenever the underlying PriceSource updates the PriceFeed with a new price. Now I want to add a feature that allows a (temporary) override to be set on the PriceFeed. The PriceSource should still update prices on the PriceFeed, but for as long as the override is set, whenever a consumer asks PriceFeed for it's current value, it should get the override. The way I did this was to introduce a new OverrideablePriceFeed that is itself both an Observer and an Observable, and that decorates the actual PriceFeed. It's implementation of .getPrice() is straight from Chain of Responsibility, but how about the handling of Observable events? When an override is set or cleared, it should issue it's own event to Observers, as well as forwarding events from the underlying PriceFeed. I think of this as some kind of a chained observer, and was curious if there's a more definitive description of a similar pattern.

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  • Code Reuse is (Damn) Hard

    - by James Michael Hare
    Being a development team lead, the task of interviewing new candidates was part of my job.  Like any typical interview, we started with some easy questions to get them warmed up and help calm their nerves before hitting the hard stuff. One of those easier questions was almost always: “Name some benefits of object-oriented development.”  Nearly every time, the candidate would chime in with a plethora of canned answers which typically included: “it helps ease code reuse.”  Of course, this is a gross oversimplification.  Tools only ease reuse, its developers that ultimately can cause code to be reusable or not, regardless of the language or methodology. But it did get me thinking…  we always used to say that as part of our mantra as to why Object-Oriented Programming was so great.  With polymorphism, inheritance, encapsulation, etc. we in essence set up the concepts to help facilitate reuse as much as possible.  And yes, as a developer now of many years, I unquestionably held that belief for ages before it really struck me how my views on reuse have jaded over the years.  In fact, in many ways Agile rightly eschews reuse as taking a backseat to developing what's needed for the here and now.  It used to be I was in complete opposition to that view, but more and more I've come to see the logic in it.  Too many times I've seen developers (myself included) get lost in design paralysis trying to come up with the perfect abstraction that would stand all time.  Nearly without fail, all of these pieces of code become obsolete in a matter of months or years. It’s not that I don’t like reuse – it’s just that reuse is hard.  In fact, reuse is DAMN hard.  Many times it is just a distraction that eats up architect and developer time, and worse yet can be counter-productive and force wrong decisions.  Now don’t get me wrong, I love the idea of reusable code when it makes sense.  These are in the few cases where you are designing something that is inherently reusable.  The problem is, most business-class code is inherently unfit for reuse! Furthermore, the code that is reusable will often fail to be reused if you don’t have the proper framework in place for effective reuse that includes standardized versioning, building, releasing, and documenting the components.  That should always be standard across the board when promoting reusable code.  All of this is hard, and it should only be done when you have code that is truly reusable or you will be exerting a large amount of development effort for very little bang for your buck. But my goal here is not to get into how to reuse (that is a topic unto itself) but what should be reused.  First, let’s look at an extension method.  There’s many times where I want to kick off a thread to handle a task, then when I want to reign that thread in of course I want to do a Join on it.  But what if I only want to wait a limited amount of time and then Abort?  Well, I could of course write that logic out by hand each time, but it seemed like a great extension method: 1: public static class ThreadExtensions 2: { 3: public static bool JoinOrAbort(this Thread thread, TimeSpan timeToWait) 4: { 5: bool isJoined = false; 6:  7: if (thread != null) 8: { 9: isJoined = thread.Join(timeToWait); 10:  11: if (!isJoined) 12: { 13: thread.Abort(); 14: } 15: } 16: return isJoined; 17: } 18: } 19:  When I look at this code, I can immediately see things that jump out at me as reasons why this code is very reusable.  Some of them are standard OO principles, and some are kind-of home grown litmus tests: Single Responsibility Principle (SRP) – The only reason this extension method need change is if the Thread class itself changes (one responsibility). Stable Dependencies Principle (SDP) – This method only depends on classes that are more stable than it is (System.Threading.Thread), and in itself is very stable, hence other classes may safely depend on it. It is also not dependent on any business domain, and thus isn't subject to changes as the business itself changes. Open-Closed Principle (OCP) – This class is inherently closed to change. Small and Stable Problem Domain – This method only cares about System.Threading.Thread. All-or-None Usage – A user of a reusable class should want the functionality of that class, not parts of that functionality.  That’s not to say they most use every method, but they shouldn’t be using a method just to get half of its result. Cost of Reuse vs. Cost to Recreate – since this class is highly stable and minimally complex, we can offer it up for reuse very cheaply by promoting it as “ready-to-go” and already unit tested (important!) and available through a standard release cycle (very important!). Okay, all seems good there, now lets look at an entity and DAO.  I don’t know about you all, but there have been times I’ve been in organizations that get the grand idea that all DAOs and entities should be standardized and shared.  While this may work for small or static organizations, it’s near ludicrous for anything large or volatile. 1: namespace Shared.Entities 2: { 3: public class Account 4: { 5: public int Id { get; set; } 6:  7: public string Name { get; set; } 8:  9: public Address HomeAddress { get; set; } 10:  11: public int Age { get; set;} 12:  13: public DateTime LastUsed { get; set; } 14:  15: // etc, etc, etc... 16: } 17: } 18:  19: ... 20:  21: namespace Shared.DataAccess 22: { 23: public class AccountDao 24: { 25: public Account FindAccount(int id) 26: { 27: // dao logic to query and return account 28: } 29:  30: ... 31:  32: } 33: } Now to be fair, I’m not saying there doesn’t exist an organization where some entites may be extremely static and unchanging.  But at best such entities and DAOs will be problematic cases of reuse.  Let’s examine those same tests: Single Responsibility Principle (SRP) – The reasons to change for these classes will be strongly dependent on what the definition of the account is which can change over time and may have multiple influences depending on the number of systems an account can cover. Stable Dependencies Principle (SDP) – This method depends on the data model beneath itself which also is largely dependent on the business definition of an account which can be very inherently unstable. Open-Closed Principle (OCP) – This class is not really closed for modification.  Every time the account definition may change, you’d need to modify this class. Small and Stable Problem Domain – The definition of an account is inherently unstable and in fact may be very large.  What if you are designing a system that aggregates account information from several sources? All-or-None Usage – What if your view of the account encompasses data from 3 different sources but you only care about one of those sources or one piece of data?  Should you have to take the hit of looking up all the other data?  On the other hand, should you have ten different methods returning portions of data in chunks people tend to ask for?  Neither is really a great solution. Cost of Reuse vs. Cost to Recreate – DAOs are really trivial to rewrite, and unless your definition of an account is EXTREMELY stable, the cost to promote, support, and release a reusable account entity and DAO are usually far higher than the cost to recreate as needed. It’s no accident that my case for reuse was a utility class and my case for non-reuse was an entity/DAO.  In general, the smaller and more stable an abstraction is, the higher its level of reuse.  When I became the lead of the Shared Components Committee at my workplace, one of the original goals we looked at satisfying was to find (or create), version, release, and promote a shared library of common utility classes, frameworks, and data access objects.  Now, of course, many of you will point to nHibernate and Entity for the latter, but we were looking at larger, macro collections of data that span multiple data sources of varying types (databases, web services, etc). As we got deeper and deeper in the details of how to manage and release these items, it quickly became apparent that while the case for reuse was typically a slam dunk for utilities and frameworks, the data access objects just didn’t “smell” right.  We ended up having session after session of design meetings to try and find the right way to share these data access components. When someone asked me why it was taking so long to iron out the shared entities, my response was quite simple, “Reuse is hard...”  And that’s when I realized, that while reuse is an awesome goal and we should strive to make code maintainable, often times you end up creating far more work for yourself than necessary by trying to force code to be reusable that inherently isn’t. Think about classes the times you’ve worked in a company where in the design session people fight over the best way to implement a class to make it maximally reusable, extensible, and any other buzzwordable.  Then think about how quickly that design became obsolete.  Many times I set out to do a project and think, “yes, this is the best design, I can extend it easily!” only to find out the business requirements change COMPLETELY in such a way that the design is rendered invalid.  Code, in general, tends to rust and age over time.  As such, writing reusable code can often be difficult and many times ends up being a futile exercise and worse yet, sometimes makes the code harder to maintain because it obfuscates the design in the name of extensibility or reusability. So what do I think are reusable components? Generic Utility classes – these tend to be small classes that assist in a task and have no business context whatsoever. Implementation Abstraction Frameworks – home-grown frameworks that try to isolate changes to third party products you may be depending on (like writing a messaging abstraction layer for publishing/subscribing that is independent of whether you use JMS, MSMQ, etc). Simplification and Uniformity Frameworks – To some extent this is similar to an abstraction framework, but there may be one chosen provider but a development shop mandate to perform certain complex items in a certain way.  Or, perhaps to simplify and dumb-down a complex task for the average developer (such as implementing a particular development-shop’s method of encryption). And what are less reusable? Application and Business Layers – tend to fluctuate a lot as requirements change and new features are added, so tend to be an unstable dependency.  May be reused across applications but also very volatile. Entities and Data Access Layers – these tend to be tuned to the scope of the application, so reusing them can be hard unless the abstract is very stable. So what’s the big lesson?  Reuse is hard.  In fact it’s damn hard.  And much of the time I’m not convinced we should focus too hard on it. If you’re designing a utility or framework, then by all means design it for reuse.  But you most also really set down a good versioning, release, and documentation process to maximize your chances.  For anything else, design it to be maintainable and extendable, but don’t waste the effort on reusability for something that most likely will be obsolete in a year or two anyway.

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  • Using the jQuery UI Library in a MVC 3 Application to Build a Dialog Form

    - by ChrisD
    Using a simulated dialog window is a nice way to handle inline data editing. The jQuery UI has a UI widget for a dialog window that makes it easy to get up and running with it in your application. With the release of ASP.NET MVC 3, Microsoft included the jQuery UI scripts and files in the MVC 3 project templates for Visual Studio. With the release of the MVC 3 Tools Update, Microsoft implemented the inclusion of those with NuGet as packages. That means we can get up and running using the latest version of the jQuery UI with minimal effort. To the code! Another that might interested you about JQuery Mobile and ASP.NET MVC 3 with C#. If you are starting with a new MVC 3 application and have the Tools Update then you are a NuGet update and a <link> and <script> tag away from adding the jQuery UI to your project. If you are using an existing MVC project you can still get the jQuery UI library added to your project via NuGet and then add the link and script tags. Assuming that you have pulled down the latest version (at the time of this publish it was 1.8.13) you can add the following link and script tags to your <head> tag: < link href = "@Url.Content(" ~ / Content / themes / base / jquery . ui . all . css ")" rel = "Stylesheet" type = "text/css" /> < script src = "@Url.Content(" ~ / Scripts / jquery-ui-1 . 8 . 13 . min . js ")" type = "text/javascript" ></ script > The jQuery UI library relies upon the CSS scripts and some image files to handle rendering of its widgets (you can choose a different theme or role your own if you like). Adding these to the stock _Layout.cshtml file results in the following markup: <!DOCTYPE html> < html > < head >     < meta charset = "utf-8" />     < title > @ViewBag.Title </ title >     < link href = "@Url.Content(" ~ / Content / Site . css ")" rel = "stylesheet" type = "text/css" />     <link href="@Url.Content("~/Content/themes/base/jquery.ui.all.css")" rel="Stylesheet" type="text/css" />     <script src="@Url.Content("~/Scripts/jquery-1.5.1.min.js")" type="text/javascript"></script>     <script src="@Url.Content("~/Scripts/modernizr-1.7.min . js ")" type = "text/javascript" ></ script >     < script src = "@Url.Content(" ~ / Scripts / jquery-ui-1 . 8 . 13 . min . js ")" type = "text/javascript" ></ script > </ head > < body >     @RenderBody() </ body > </ html > Our example will involve building a list of notes with an id, title and description. Each note can be edited and new notes can be added. The user will never have to leave the single page of notes to manage the note data. The add and edit forms will be delivered in a jQuery UI dialog widget and the note list content will get reloaded via an AJAX call after each change to the list. To begin, we need to craft a model and a data management class. We will do this so we can simulate data storage and get a feel for the workflow of the user experience. The first class named Note will have properties to represent our data model. namespace Website . Models {     public class Note     {         public int Id { get ; set ; }         public string Title { get ; set ; }         public string Body { get ; set ; }     } } The second class named NoteManager will be used to set up our simulated data storage and provide methods for querying and updating the data. We will take a look at the class content as a whole and then walk through each method after. using System . Collections . ObjectModel ; using System . Linq ; using System . Web ; namespace Website . Models {     public class NoteManager     {         public Collection < Note > Notes         {             get             {                 if ( HttpRuntime . Cache [ "Notes" ] == null )                     this . loadInitialData ();                 return ( Collection < Note >) HttpRuntime . Cache [ "Notes" ];             }         }         private void loadInitialData ()         {             var notes = new Collection < Note >();             notes . Add ( new Note                           {                               Id = 1 ,                               Title = "Set DVR for Sunday" ,                               Body = "Don't forget to record Game of Thrones!"                           });             notes . Add ( new Note                           {                               Id = 2 ,                               Title = "Read MVC article" ,                               Body = "Check out the new iwantmymvc.com post"                           });             notes . Add ( new Note                           {                               Id = 3 ,                               Title = "Pick up kid" ,                               Body = "Daughter out of school at 1:30pm on Thursday. Don't forget!"                           });             notes . Add ( new Note                           {                               Id = 4 ,                               Title = "Paint" ,                               Body = "Finish the 2nd coat in the bathroom"                           });             HttpRuntime . Cache [ "Notes" ] = notes ;         }         public Collection < Note > GetAll ()         {             return Notes ;         }         public Note GetById ( int id )         {             return Notes . Where ( i => i . Id == id ). FirstOrDefault ();         }         public int Save ( Note item )         {             if ( item . Id <= 0 )                 return saveAsNew ( item );             var existingNote = Notes . Where ( i => i . Id == item . Id ). FirstOrDefault ();             existingNote . Title = item . Title ;             existingNote . Body = item . Body ;             return existingNote . Id ;         }         private int saveAsNew ( Note item )         {             item . Id = Notes . Count + 1 ;             Notes . Add ( item );             return item . Id ;         }     } } The class has a property named Notes that is read only and handles instantiating a collection of Note objects in the runtime cache if it doesn't exist, and then returns the collection from the cache. This property is there to give us a simulated storage so that we didn't have to add a full blown database (beyond the scope of this post). The private method loadInitialData handles pre-filling the collection of Note objects with some initial data and stuffs them into the cache. Both of these chunks of code would be refactored out with a move to a real means of data storage. The GetAll and GetById methods access our simulated data storage to return all of our notes or a specific note by id. The Save method takes in a Note object, checks to see if it has an Id less than or equal to zero (we assume that an Id that is not greater than zero represents a note that is new) and if so, calls the private method saveAsNew . If the Note item sent in has an Id , the code finds that Note in the simulated storage, updates the Title and Description , and returns the Id value. The saveAsNew method sets the Id , adds it to the simulated storage, and returns the Id value. The increment of the Id is simulated here by getting the current count of the note collection and adding 1 to it. The setting of the Id is the only other chunk of code that would be refactored out when moving to a different data storage approach. With our model and data manager code in place we can turn our attention to the controller and views. We can do all of our work in a single controller. If we use a HomeController , we can add an action method named Index that will return our main view. An action method named List will get all of our Note objects from our manager and return a partial view. We will use some jQuery to make an AJAX call to that action method and update our main view with the partial view content returned. Since the jQuery AJAX call will cache the call to the content in Internet Explorer by default (a setting in jQuery), we will decorate the List, Create and Edit action methods with the OutputCache attribute and a duration of 0. This will send the no-cache flag back in the header of the content to the browser and jQuery will pick that up and not cache the AJAX call. The Create action method instantiates a new Note model object and returns a partial view, specifying the NoteForm.cshtml view file and passing in the model. The NoteForm view is used for the add and edit functionality. The Edit action method takes in the Id of the note to be edited, loads the Note model object based on that Id , and does the same return of the partial view as the Create method. The Save method takes in the posted Note object and sends it to the manager to save. It is decorated with the HttpPost attribute to ensure that it will only be available via a POST. It returns a Json object with a property named Success that can be used by the UX to verify everything went well (we won't use that in our example). Both the add and edit actions in the UX will post to the Save action method, allowing us to reduce the amount of unique jQuery we need to write in our view. The contents of the HomeController.cs file: using System . Web . Mvc ; using Website . Models ; namespace Website . Controllers {     public class HomeController : Controller     {         public ActionResult Index ()         {             return View ();         }         [ OutputCache ( Duration = 0 )]         public ActionResult List ()         {             var manager = new NoteManager ();             var model = manager . GetAll ();             return PartialView ( model );         }         [ OutputCache ( Duration = 0 )]         public ActionResult Create ()         {             var model = new Note ();             return PartialView ( "NoteForm" , model );         }         [ OutputCache ( Duration = 0 )]         public ActionResult Edit ( int id )         {             var manager = new NoteManager ();             var model = manager . GetById ( id );             return PartialView ( "NoteForm" , model );         }         [ HttpPost ]         public JsonResult Save ( Note note )         {             var manager = new NoteManager ();             var noteId = manager . Save ( note );             return Json ( new { Success = noteId > 0 });         }     } } The view for the note form, NoteForm.cshtml , looks like so: @model Website . Models . Note @using ( Html . BeginForm ( "Save" , "Home" , FormMethod . Post , new { id = "NoteForm" })) { @Html . Hidden ( "Id" ) < label class = "Title" >     < span > Title < /span><br / >     @Html . TextBox ( "Title" ) < /label> <label class="Body">     <span>Body</ span >< br />     @Html . TextArea ( "Body" ) < /label> } It is a strongly typed view for our Note model class. We give the <form> element an id attribute so that we can reference it via jQuery. The <label> and <span> tags give our UX some structure that we can style with some CSS. The List.cshtml view is used to render out a <ul> element with all of our notes. @model IEnumerable < Website . Models . Note > < ul class = "NotesList" >     @foreach ( var note in Model )     {     < li >         @note . Title < br />         @note . Body < br />         < span class = "EditLink ButtonLink" noteid = "@note.Id" > Edit < /span>     </ li >     } < /ul> This view is strongly typed as well. It includes a <span> tag that we will use as an edit button. We add a custom attribute named noteid to the <span> tag that we can use in our jQuery to identify the Id of the note object we want to edit. The view, Index.cshtml , contains a bit of html block structure and all of our jQuery logic code. @ {     ViewBag . Title = "Index" ; } < h2 > Notes < /h2> <div id="NoteListBlock"></ div > < span class = "AddLink ButtonLink" > Add New Note < /span> <div id="NoteDialog" title="" class="Hidden"></ div > < script type = "text/javascript" >     $ ( function () {         $ ( "#NoteDialog" ). dialog ({             autoOpen : false , width : 400 , height : 330 , modal : true ,             buttons : {                 "Save" : function () {                     $ . post ( "/Home/Save" ,                         $ ( "#NoteForm" ). serialize (),                         function () {                             $ ( "#NoteDialog" ). dialog ( "close" );                             LoadList ();                         });                 },                 Cancel : function () { $ ( this ). dialog ( "close" ); }             }         });         $ ( ".EditLink" ). live ( "click" , function () {             var id = $ ( this ). attr ( "noteid" );             $ ( "#NoteDialog" ). html ( "" )                 . dialog ( "option" , "title" , "Edit Note" )                 . load ( "/Home/Edit/" + id , function () { $ ( "#NoteDialog" ). dialog ( "open" ); });         });         $ ( ".AddLink" ). click ( function () {             $ ( "#NoteDialog" ). html ( "" )                 . dialog ( "option" , "title" , "Add Note" )                 . load ( "/Home/Create" , function () { $ ( "#NoteDialog" ). dialog ( "open" ); });         });         LoadList ();     });     function LoadList () {         $ ( "#NoteListBlock" ). load ( "/Home/List" );     } < /script> The <div> tag with the id attribute of "NoteListBlock" is used as a container target for the load of the partial view content of our List action method. It starts out empty and will get loaded with content via jQuery once the DOM is loaded. The <div> tag with the id attribute of "NoteDialog" is the element for our dialog widget. The jQuery UI library will use the title attribute for the text in the dialog widget top header bar. We start out with it empty here and will dynamically change the text via jQuery based on the request to either add or edit a note. This <div> tag is given a CSS class named "Hidden" that will set the display:none style on the element. Since our call to the jQuery UI method to make the element a dialog widget will occur in the jQuery document ready code block, the end user will see the <div> element rendered in their browser as the page renders and then it will hide after that jQuery call. Adding the display:hidden to the <div> element via CSS will ensure that it is never rendered until the user triggers the request to open the dialog. The jQuery document load block contains the setup for the dialog node, click event bindings for the edit and add links, and a call to a JavaScript function called LoadList that handles the AJAX call to the List action method. The .dialog() method is called on the "NoteDialog" <div> element and the options are set for the dialog widget. The buttons option defines 2 buttons and their click actions. The first is the "Save" button (the text in quotations is used as the text for the button) that will do an AJAX post to our Save action method and send the serialized form data from the note form (targeted with the id attribute "NoteForm"). Upon completion it will close the dialog widget and call the LoadList to update the UX without a redirect. The "Cancel" button simply closes the dialog widget. The .live() method handles binding a function to the "click" event on all elements with the CSS class named EditLink . We use the .live() method because it will catch and bind our function to elements even as the DOM changes. Since we will be constantly changing the note list as we add and edit we want to ensure that the edit links get wired up with click events. The function for the click event on the edit links gets the noteid attribute and stores it in a local variable. Then it clears out the HTML in the dialog element (to ensure a fresh start), calls the .dialog() method and sets the "title" option (this sets the title attribute value), and then calls the .load() AJAX method to hit our Edit action method and inject the returned content into the "NoteDialog" <div> element. Once the .load() method is complete it opens the dialog widget. The click event binding for the add link is similar to the edit, only we don't need to get the id value and we load the Create action method. This binding is done via the .click() method because it will only be bound on the initial load of the page. The add button will always exist. Finally, we toss in some CSS in the Content/Site.css file to style our form and the add/edit links. . ButtonLink { color : Blue ; cursor : pointer ; } . ButtonLink : hover { text - decoration : underline ; } . Hidden { display : none ; } #NoteForm label { display:block; margin-bottom:6px; } #NoteForm label > span { font-weight:bold; } #NoteForm input[type=text] { width:350px; } #NoteForm textarea { width:350px; height:80px; } With all of our code in place we can do an F5 and see our list of notes: If we click on an edit link we will get the dialog widget with the correct note data loaded: And if we click on the add new note link we will get the dialog widget with the empty form: The end result of our solution tree for our sample:

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