Search Results

Search found 97822 results on 3913 pages for 'static code analysis'.

Page 489/3913 | < Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >

  • Please help me to improve Re-Sharper

    - by TATWORTH
    Re-Sharper is an excellent aid to producing good code in either C# or VB.NET. Recently through using Resharper and StyleCop, I have found three area where ReSharper needs to be improved. Please log into the YouTrack at http://youtrack.jetbrains.net and vote for the following: RSRP-268868 Improvement to removal of redundant else and invert if optimisations for enhanced stylecop compliance. When Resharper removes a redundant else, there needs to be a blank line added. Currently there is no provision to specify this. Please vote for this! RSRP-272286 Resharper Feature Request to move initialisation to static constructor Currently ReSharper offers moving initialisation of of non-static variable to a constructor. Why not offer the same for a static constructor?  Please vote for this! RSRP-272285 Expansion of Switch Statement by Resharper Currently ReSharper will fill an empty switch statement based upon an enumeration but will not add missing enumeration values to such a switch statement.   Can't code withoutCoding assistance, smart code editing and code completion for C# and VB.NET

    Read the article

  • Passing class names or objects?

    - by nischayn22
    I have a switch statement switch ( $id ) { case 'abc': return 'Animal'; case 'xyz': return 'Human'; //many more } I am returning class names,and use them to call some of their static functions using call_user_func(). Instead I can also create a object of that class, return that and then call the static function from that object as $object::method($param) switch ( $id ) { case 'abc': return new Animal; case 'xyz': return new Human; //many more } Which way is efficient? To make this question broader : I have classes that have mostly all static methods right now, putting them into classes is kind of a grouping idea here (for example the DB table structure of Animal is given by class Animal and so for Human class). I need to access many functions from these classes so the switch needs to give me access to the class

    Read the article

  • How to write this kind of java source in clojure. [closed]

    - by tikky
    I want to know how to write a clojure code by looking at a java code like this. import xxxxxx import com.vaadin.terminal.gwt.server.AbstractApplicationServlet; public class Clojure4Vaadin extends AbstractApplicationServlet { @Override protected Class <? extends Application > getApplicationClass() throws ClassNotFoundException { return Application.class; } @Override protected Application getNewApplication(HttpServletRequest request) throws ServletException { try { RT.load(getServletConfig().getInitParameter("script-name"), true); //run Lisp function return (Application)RT.var(getServletConfig().getInitParameter("package-name"),getServletConfig().getInitParameter("function-name")).invoke(new String[0]); } catch (Exception e) { throw new ServletException(e); } } } I need to write a code clojure code which can do the sane thing that this java code can do.

    Read the article

  • Where should I put a method that returns a list of active entries of a table?

    - by darga33
    I have a class named GuestbookEntry that maps to the properties that are in the database table named "guestbook". Very simple! Originally, I had a static method named getActiveEntries() that retrieved an array of all GuestbookEntry objects. Each row in the guestbook table was an object that was added to that array. Then while learning how to properly design PHP classes, I learned some things: Static methods are not desirable. Separation of Concerns Single Responsibility Principle If the GuestbookEntry class should only be responsible for managing single guestbook entries then where should this getActiveEntries() method most properly go? Update: I am looking for an answer that complies with the SOLID acronym principles and allows for test-ability. That's why I want to stay away from static calls/standard functions. DAO, repository, ...? Please explain as though your explanation will be part of "Where to Locate FOR DUMMIES"... :-)

    Read the article

  • xUnit global setup / teardown [migrated]

    - by Codism
    I need to run some code before any test is executed and also some code after all tests are done. I thought there must be some attributes or marker interface to indicate the global initialization and termination code but couldn't find them. Alternatively, if I can invoke xUnit programmatically, I can also achieve what I want to do by the following code: ... Main(string[] args) { try { MyGlobalSetup(); RunAllTests(); // What goes into this method? } finally { MyGlobalTeardown(); } } Can anyone provide me some hint about how to declaratively or programmally run some global setup/teardown code? Thanks

    Read the article

  • Naming convention: field starting with "m" or "s"

    - by Noya
    Hope this question hasn't posted yet... I saw lot of code (for example some Android source code) where fields name start with a "m" while static fields start with "s" Example (taken from Android View class source): private SparseArray<Object> mKeyedTags; private static int sNextAccessibilityViewId; I was wondering what "m" and "s" stand for... maybe is "m" mutable and "s" static? Since it seems that is a largely adopted pattern do you know if there some literature about this kind of naming convention?

    Read the article

  • MAC filtering after DHCP

    - by user1655161
    How to manage filtering by MAC in Ubuntu? Scenario: Ubuntu DHCP is configured and working (network 192.168.1.0) a) Laptop 1 is set in configuration on Ubuntu as static IP Laptop 1 is configured for automatic IP and when is connected to server everything works. I'm taking laptop 2 which is configured as static IP 192.168.1.10 and his configuration is not set in Ubuntu dhcpd.conf After laptop 2 is connected internet working. It is possible to do MAC filtering which disallow to connect PCs with address IP set as static but MAC address is not configured in Ubuntu (something like: intruder in network)?

    Read the article

  • Is it necessary to memorize codes?

    - by AAA
    I am a new developer, who just got hired at a big company. I don't know how but I guess they are desperate. However, I am well-versed with HTML5/CSS3 though things change and new things are released and I keep up with as much as I can. But this job required me to hand-code Javascript, know Jquery and Ajax. I have been exposed to this a bit but I am not sure if I can hand-code Javascript. My question is, is it necessary to memorize all there is about Javascript or are there a few key things that I should know how to hand-code because looking at javascript code it seems there are lots of lines code! Please point me in the right direction.

    Read the article

  • What would be a good way to request comments?

    - by WarpEnterprises
    In the project/team I'm working the frequency of comments is a little low. One reason might be that it is not clear to the long-time devs what lines in the code really needs a comment (each part of the project has quite fixed devs). To increase this we plan to let team members review the code and check in "requests for comments", which the main dev of that part should replace with useful comments. Do you think this could work? If "yes": what tags should we use to mark? (e.g. //TODO please comment) Can you think of alternatives for this process? Edit: I appreciate your answers about best practice in commenting and writing code, and I completey agree. But my question targets the cases where refactoring is not an option (not wanting to change working code, not wanting to "accuse" main dev of producing code that needs refactoring,...) - so only more or better comments are an option (at least for this question).

    Read the article

  • Release Notes for 5/31/2012

    Here are the notes for this week’s release: Pull Requests We’ve moved the pull request creation UI from a modal dialog to a full page to make room for more context on what you’re sending with your pull request. In this week’s changes, you’ll see the list of commits; look for diffs to appear in the coming weeks. Corrected several issues where the line that had comments associated was not being properly differentiated in the code snippet previews on pull request discussions. Corrected an issue where pull request line comments would not appear to be associated with the proper line of code. Fixed an issue where accepting pull requests was not working properly. Bug Fixes Fixed an issue where code snippets could not be inserted using Opera. Fixed an issue where Internet Explorer displayed an error message when browsing the site using https. Fixed an issue where the CAPTCHA was not displaying properly on the Contact User page. Fixed an issue where paging was not working properly in the “Recent Release in Followed Projects” sections for logged in users. Other Updated the activity stream to no longer auto-load new items when scrolling down. Added an explicit download link at the end of the download countdown in case certain browsers/scenarios don’t automatically start downloading. Have ideas on how to improve CodePlex? Visit our ideas page! Vote for your favorite ideas or submit a new one. Got Twitter? Follow us and keep apprised of the latest releases and service status at @codeplex.

    Read the article

  • Where would a senior PHP developer locate the method getActiveEntries()?

    - by darga33
    I have a class named GuestbookEntry that maps to the properties that are in the database table named "guestbook". Very simple! Originally, I had a static method named getActiveEntries() that retrieved an array of all GuestbookEntry objects. Each row in the guestbook table was an object that was added to that array. Then while learning how to properly design PHP classes, I learned some things: Static methods are not desirable. Separation of Concerns Single Responsibility Principle If the GuestbookEntry class should only be responsible for managing single guestbook entries then where should this getActiveEntries() method most properly go? Update: I am looking for an answer that complies with the SOLID acronym principles and allows for test-ability. That's why I want to stay away from static calls/standard functions. DAO, repository, ...? Please explain as though your explanation will be part of "Where to Locate FOR DUMMIES"... :-)

    Read the article

  • Release Notes for 6/28/2012

    Here are the notes for this week’s release on CodePlex: Improved the diff viewer to take you directly to the first diff when viewing a file’s diff. We decreased the size of all of our form elements to be more in line with the rest of the content of our site. Fixed various issues around interacting with the diff viewer, especially around scrolling and interacting with the splitter. Fixed an issue where non-project members were seeing inapplicable TFS connection instructions when clicking on the source code details of a project. Fixed an issue where searching with the enter key on the advanced issue tracker was not working. Removed the confirmation pop-up when picking SVN as a source control option. Fixed an issue where the bulk editing dialog of issues in Internet Explorer would become unusable if there were values to choose. Fixed an issue where project logos would not show up when browsing under https in FireFox and Chrome. Fixed an issue affecting the formatting of code in pull request code comment notifications. Have ideas on how to improve CodePlex? Visit our ideas page! Vote for your favorite ideas or submit a new one. Got Twitter? Follow us and keep apprised of the latest releases and service status at @codeplex.

    Read the article

  • System.getProperty("user.dir") cannot get my project root path ,but the path which my eclipse is located

    - by facebook-100005613813158
    As the title goes , I have class named GetException.java,inside it ,I read a xml file in a static code block like(Because this document is shared): static{ ... document = db.parse(new File(System.getProperty("user.dir")+"/src/exception/ExceptionCode.xml")); ... } To test if the file path is correct, I write a main function just inside GetException.java, it proves that the path is correct ,xml file can be read successfully. My project root dir is "/home/wuchang/workspace/MongodbI". But When this Class is loaded from other class,such as I called one of its static functions , it reports the error message: /home/mrs/??/eclipse/src/exception/ExceptionCode.xml (No such file or directory) /home/mrs/??/eclipse/ is actually my eclipse installation directory.So , I wander how System.getProperty("user.dir") returned the eclipse installation directory to me ,instead of my project root directory?

    Read the article

  • Did a bunch of wrong work, should I keep it?

    - by Droogans
    I have forked a repo and branched that clone to code a story, and because I didn't understand the problem, wrote code that isn't solving my task at hand, but may prove useful later. Should I: Delete it, and don't worry about it. Then commit without the extra code. Make yet another branch for just that work, commit it, but don't post a pull request on it. Just commit it with the existing code, and worry about the extra "fluff" later. I was thinking #2. If I understand correctly, I could just keep the extra code on a branch I never use on my clone, and dig it up later if something comes up that may benefit from using it.

    Read the article

  • Release Notes for 6/21/2012

    Here are the notes for this week’s release on CodePlex: Pull Requests We now support the ability to conduct pull requests in Git and Mercurial across arbitrary branches in your project. No forks necessary! If you’re on a small team of contributors, this is a great way to conduct code reviews for changes to your project. We now support e-mail notifications to be delivered whenever a comment is added to a pull request or line of code pertaining to a pull request. A checkbox for subscribing now appears at the bottom of all pull requests. You can manage your subscriptions by editing your profile. Bug Fixes Updated the various change subscription details page to reflect our newer UI theme. Changed the placement of horizontal scrollbar when viewing diffs of pull requests and commits to be inline with the code. Fixed various issues around interacting with the new diff viewer that we introduced last week. Do let us know if you have any feedback on the new diff viewer. Have ideas on how to improve CodePlex? Visit our ideas page! Vote for your favorite ideas or submit a new one. Got Twitter? Follow us and keep apprised of the latest releases and service status at @codeplex.

    Read the article

  • Question about main(String[] args) [migrated]

    - by Andrew0085
    I'm new to programming, and I'm using java. Here's a program I wrote: class HelloApp { static String hi; public static void main(String[] args) { int length = args.length; if (length > 0) { hi = args[0]; sayHi(); } } static void sayHi() { if (hi == "hello") { System.out.println("Hello!"); } } } My question is: Why doesn't inputting "java HelloApp hello" make "Hello!" appear on the next line?

    Read the article

  • OOP vs PP for algorithms

    - by Ilian
    Which paradigm is better for design and analysis of algorithms? Which is faster? Because I have a subject called Design and Analysis of Algorithms in university and have a time limit for programs. Is OOP slower than Procedure programming? Or the time difference is not big?

    Read the article

  • First Party and Third Party Cookie

    - by ajithperuva
    I want to create a analysis project (just like google analysis),for getting conversion rate and track visitor count.How can we create first party cookie and third party cookie using php.Actually, how can we identify our third party and first party cookie.Need to follow any type of standard for identify them?if anybody know please give me some idea about it...please

    Read the article

  • Motion detection in compressed domain (JPEG/Mpeg4/H264)

    - by paft
    everyone! I process video from IP cameras and have wrote a motion detection algorithm based on decompressed video analysis. But i really something more fast. I've found several papers about compressed domain analysis but have failed to find any implementations. Can anyone recommend me some code? found materials: http://www.ist-live.org/intranet/school-of-informatics-university-of-bradford001-7/41410206.pdf/view http://doc.rero.ch/lm.php?url=1000,43,4,20061128120121-NA/Bracamonte_Javier_-_A_Low_Complexity_Change_Detection_Algorithm_20061128.pdf

    Read the article

  • How do you combine "Revision Control" with "WorkFlow" for R?

    - by Tal Galili
    Hello all, I remember coming across R users writing that they use "Revision control" (e.g: "Source control"), and I am curious to know: How do you combine "Revision control" with your statistical analysis WorkFlow? Two (very) interesting discussions talk about how to deal with the WorkFlow. But neither of them refer to the revision control element: http://stackoverflow.com/questions/1266279/how-to-organize-large-r-programs http://stackoverflow.com/questions/1429907/workflow-for-statistical-analysis-and-report-writing A Long Update To The Question: Following some of the people's answers, and Dirk's question in the comment, I would like to direct my question a bit more. After reading the Wiki article about "revision control" (which I was previously not familiar with), it was clear to me that when using revision control, what one does is to build a development structure of his code. This structure either leads to a "final product" or to several branches. When building something like, let's say, a website. There is usually one end product you work towards (the website), with some prototypes along the way. But when doing a statistical analysis, the work (to my view) is different. Sometimes you know where you want to get to. But more often, you explore. Explore cleaning the dataset. Explore different methods for statistical analysis, and ask various questions of your data (and I am writing this, knowing how Frank Harrell, and other experience statisticians feels about Data dredging). That is way the WorkFlow question with statistical programming is (in my view) a serious and deep question, raising many issues, The simpler ones are technical: Which revision control software do you use (and why) ? Which IDE do you use(and why) ? The more interesting question are about work process: How do you structure your files? What do you keep as a separate file and what as a revision? or asking in a different way - What should be a "branch" and what should be a "sub project" in your code? For example: When starting to explore your data, should a plot be creating and then erased because it didn't lead any where (but kept as a revision) or should there be a backup file of that path? How you solve this tension was my initial curiosity. The second question is "what might I be missing?". What rules (of thumb) should one follow so to avoid common pitfalls doing statistical programming with version control? In my intuition, I feel that statistical programming is inherently different then software development (I am writing this without being a real expert in statistical programming, and even less so in software development). That's way I am unsure which of the lessons I have read here about version control would be applicable. Thanks a lot, Tal

    Read the article

  • Dynamically loaded jQuery with GreaseMonkey inconsistent on pages (refreshing seems to fix it)... do

    - by uprightnetizen
    Hi, I want a custom page analysis footer on every site I visit... so I've used a method to attach JQuery to unsafeWindow. I then create a floating footer on the page. I want to be able to call commands in a menu, do some processing, then put the results in the footer. Unfortunately it sometimes works, sometimes it doesn't. At least two alerts should happen in the printOutput function. Sometimes it only fires one, then it (crashes?) without error? On other pages, both alerts fire and it finds the element, but it doesn't add the extra text. (e.g. www.linode.com) Refreshing the page, then running the printOutput command again seems to always work. Does anyone know what's going on??? The userscript can be installed at: http://www.captionwizard.com/test/page_analysis.user.js // ==UserScript== // @name page_analysis // @namespace markspace // @description Page Analysis // @include http://*/* // ==/UserScript== (function() { // Add jQuery var GM_JQ = document.createElement('script'); GM_JQ.src = 'http://code.jquery.com/jquery-1.4.2.min.js'; GM_JQ.type = 'text/javascript'; document.getElementsByTagName('head')[0].appendChild(GM_JQ); var jqueryActive = false; //Check if jQuery's loaded function GM_wait() { if(typeof unsafeWindow.jQuery == 'undefined') { window.setTimeout(GM_wait,100); } else { $ = unsafeWindow.jQuery; letsJQuery(); } } GM_wait(); function letsJQuery() { jqueryActive = true; setupOutputFooter(); } /******************************* Analysis FOOTER Functions ******************************/ function printOutput(someText) { alert('printing output'); if($('div.analysis_footer').length) { alert('is here - appending'); $('div.analysis_footer').append('<br>' + someText); } else { alert('not here - trying again'); setupOutputFooter(); $('div.analysis_footer').append('<br>' + someText); } } GM_registerMenuCommand("Test Output", testOutput, "k", "control", "k" ); function testOutput() { printOutput('testing this'); } function setupOutputFooter() { $('<div class="analysis_footer">Page Analysis Footer:</div>').appendTo('body'); $('div.analysis_footer').css('position','fixed').css('bottom', '0px').css('background-color','#F8F8F8'); $('div.analysis_footer').css('width','100%').css('color','#3B3B3B').css('font-size', '0.8em'); $('div.analysis_footer').css('font-family', '"Myriad",Verdana,Arial,Helvetica,sans-serif').css('padding', '5px'); $('div.analysis_footer').css('border-top', '1px solid black').css('text-align', 'left'); } }());

    Read the article

  • What does the symbol ::: mean in R

    - by Milktrader
    I came across this in the following context from B. Pfaff's "Analysis of Integrated and Cointegrated Time Series in R" ## Impulse response analysis of SVAR A-type model 1 args (vars ::: irf.svarest) 2 irf.svara <- irf (svar.A, impulse = ”y1 ” , 3 response = ”y2 ” , boot = FALSE) 4 args (vars ::: plot.varirf) 5 plot (irf.svara)

    Read the article

  • Metro: Creating an IndexedDbDataSource for WinJS

    - by Stephen.Walther
    The goal of this blog entry is to describe how you can create custom data sources which you can use with the controls in the WinJS library. In particular, I explain how you can create an IndexedDbDataSource which you can use to store and retrieve data from an IndexedDB database. If you want to skip ahead, and ignore all of the fascinating content in-between, I’ve included the complete code for the IndexedDbDataSource at the very bottom of this blog entry. What is IndexedDB? IndexedDB is a database in the browser. You can use the IndexedDB API with all modern browsers including Firefox, Chrome, and Internet Explorer 10. And, of course, you can use IndexedDB with Metro style apps written with JavaScript. If you need to persist data in a Metro style app written with JavaScript then IndexedDB is a good option. Each Metro app can only interact with its own IndexedDB databases. And, IndexedDB provides you with transactions, indices, and cursors – the elements of any modern database. An IndexedDB database might be different than the type of database that you normally use. An IndexedDB database is an object-oriented database and not a relational database. Instead of storing data in tables, you store data in object stores. You store JavaScript objects in an IndexedDB object store. You create new IndexedDB object stores by handling the upgradeneeded event when you attempt to open a connection to an IndexedDB database. For example, here’s how you would both open a connection to an existing database named TasksDB and create the TasksDB database when it does not already exist: var reqOpen = window.indexedDB.open(“TasksDB”, 2); reqOpen.onupgradeneeded = function (evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); }; reqOpen.onsuccess = function () { var db = reqOpen.result; // Do something with db }; When you call window.indexedDB.open(), and the database does not already exist, then the upgradeneeded event is raised. In the code above, the upgradeneeded handler creates a new object store named tasks. The new object store has an auto-increment column named id which acts as the primary key column. If the database already exists with the right version, and you call window.indexedDB.open(), then the success event is raised. At that point, you have an open connection to the existing database and you can start doing something with the database. You use asynchronous methods to interact with an IndexedDB database. For example, the following code illustrates how you would add a new object to the tasks object store: var transaction = db.transaction(“tasks”, “readwrite”); var reqAdd = transaction.objectStore(“tasks”).add({ name: “Feed the dog” }); reqAdd.onsuccess = function() { // Tasks added successfully }; The code above creates a new database transaction, adds a new task to the tasks object store, and handles the success event. If the new task gets added successfully then the success event is raised. Creating a WinJS IndexedDbDataSource The most powerful control in the WinJS library is the ListView control. This is the control that you use to display a collection of items. If you want to display data with a ListView control, you need to bind the control to a data source. The WinJS library includes two objects which you can use as a data source: the List object and the StorageDataSource object. The List object enables you to represent a JavaScript array as a data source and the StorageDataSource enables you to represent the file system as a data source. If you want to bind an IndexedDB database to a ListView then you have a choice. You can either dump the items from the IndexedDB database into a List object or you can create a custom data source. I explored the first approach in a previous blog entry. In this blog entry, I explain how you can create a custom IndexedDB data source. Implementing the IListDataSource Interface You create a custom data source by implementing the IListDataSource interface. This interface contains the contract for the methods which the ListView needs to interact with a data source. The easiest way to implement the IListDataSource interface is to derive a new object from the base VirtualizedDataSource object. The VirtualizedDataSource object requires a data adapter which implements the IListDataAdapter interface. Yes, because of the number of objects involved, this is a little confusing. Your code ends up looking something like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); The code above is used to create a new class named IndexedDbDataSource which derives from the base VirtualizedDataSource class. In the constructor for the new class, the base class _baseDataSourceConstructor() method is called. A data adapter is passed to the _baseDataSourceConstructor() method. The code above creates a new method exposed by the IndexedDbDataSource named nuke(). The nuke() method deletes all of the objects from an object store. The code above also overrides a method named remove(). Our derived remove() method accepts any type of key and removes the matching item from the object store. Almost all of the work of creating a custom data source goes into building the data adapter class. The data adapter class implements the IListDataAdapter interface which contains the following methods: · change() · getCount() · insertAfter() · insertAtEnd() · insertAtStart() · insertBefore() · itemsFromDescription() · itemsFromEnd() · itemsFromIndex() · itemsFromKey() · itemsFromStart() · itemSignature() · moveAfter() · moveBefore() · moveToEnd() · moveToStart() · remove() · setNotificationHandler() · compareByIdentity Fortunately, you are not required to implement all of these methods. You only need to implement the methods that you actually need. In the case of the IndexedDbDataSource, I implemented the getCount(), itemsFromIndex(), insertAtEnd(), and remove() methods. If you are creating a read-only data source then you really only need to implement the getCount() and itemsFromIndex() methods. Implementing the getCount() Method The getCount() method returns the total number of items from the data source. So, if you are storing 10,000 items in an object store then this method would return the value 10,000. Here’s how I implemented the getCount() method: getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); } The first thing that you should notice is that the getCount() method returns a WinJS promise. This is a requirement. The getCount() method is asynchronous which is a good thing because all of the IndexedDB methods (at least the methods implemented in current browsers) are also asynchronous. The code above retrieves an object store and then uses the IndexedDB count() method to get a count of the items in the object store. The value is returned from the promise by calling complete(). Implementing the itemsFromIndex method When a ListView displays its items, it calls the itemsFromIndex() method. By default, it calls this method multiple times to get different ranges of items. Three parameters are passed to the itemsFromIndex() method: the requestIndex, countBefore, and countAfter parameters. The requestIndex indicates the index of the item from the database to show. The countBefore and countAfter parameters represent hints. These are integer values which represent the number of items before and after the requestIndex to retrieve. Again, these are only hints and you can return as many items before and after the request index as you please. Here’s how I implemented the itemsFromIndex method: itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); } In the code above, a cursor is used to iterate through the objects in an object store. You fetch the next item in the cursor by calling either the cursor.continue() or cursor.advance() method. The continue() method moves forward by one object and the advance() method moves forward a specified number of objects. Each time you call continue() or advance(), the success event is raised again. If the cursor is null then you know that you have reached the end of the cursor and you can return the results. Some things to be careful about here. First, the return value from the itemsFromIndex() method must implement the IFetchResult interface. In particular, you must return an object which has an items, offset, and totalCount property. Second, each item in the items array must implement the IListItem interface. Each item should have a key and a data property. Implementing the insertAtEnd() Method When creating the IndexedDbDataSource, I wanted to go beyond creating a simple read-only data source and support inserting and deleting objects. If you want to support adding new items with your data source then you need to implement the insertAtEnd() method. Here’s how I implemented the insertAtEnd() method for the IndexedDbDataSource: insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); } When implementing the insertAtEnd() method, you need to be careful to return an object which implements the IItem interface. In particular, you should return an object that has a key and a data property. The key must be a string and it uniquely represents the new item added to the data source. The value of the data property represents the new item itself. Implementing the remove() Method Finally, you use the remove() method to remove an item from the data source. You call the remove() method with the key of the item which you want to remove. Implementing the remove() method in the case of the IndexedDbDataSource was a little tricky. The problem is that an IndexedDB object store uses an integer key and the VirtualizedDataSource requires a string key. For that reason, I needed to override the remove() method in the derived IndexedDbDataSource class like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); When you call remove(), you end up calling a method of the IndexedDbDataAdapter named removeInternal() . Here’s what the removeInternal() method looks like: setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); } The removeInternal() method calls the IndexedDB delete() method to delete an item from the object store. If the item is deleted successfully then the _notificationHandler.remove() method is called. Because we are not implementing the standard IListDataAdapter remove() method, we need to notify the data source (and the ListView control bound to the data source) that an item has been removed. The way that you notify the data source is by calling the _notificationHandler.remove() method. Notice that we get the _notificationHandler in the code above by implementing another method in the IListDataAdapter interface: the setNotificationHandler() method. You can raise the following types of notifications using the _notificationHandler: · beginNotifications() · changed() · endNotifications() · inserted() · invalidateAll() · moved() · removed() · reload() These methods are all part of the IListDataNotificationHandler interface in the WinJS library. Implementing the nuke() Method I wanted to implement a method which would remove all of the items from an object store. Therefore, I created a method named nuke() which calls the IndexedDB clear() method: nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); } Notice that the nuke() method calls the _notificationHandler.reload() method to notify the ListView to reload all of the items from its data source. Because we are implementing a custom method here, we need to use the _notificationHandler to send an update. Using the IndexedDbDataSource To illustrate how you can use the IndexedDbDataSource, I created a simple task list app. You can add new tasks, delete existing tasks, and nuke all of the tasks. You delete an item by selecting an item (swipe or right-click) and clicking the Delete button. Here’s the HTML page which contains the ListView, the form for adding new tasks, and the buttons for deleting and nuking tasks: <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>DataSources</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.1.0.RC/css/ui-dark.css" rel="stylesheet" /> <script src="//Microsoft.WinJS.1.0.RC/js/base.js"></script> <script src="//Microsoft.WinJS.1.0.RC/js/ui.js"></script> <!-- DataSources references --> <link href="indexedDb.css" rel="stylesheet" /> <script type="text/javascript" src="indexedDbDataSource.js"></script> <script src="indexedDb.js"></script> </head> <body> <div id="tmplTask" data-win-control="WinJS.Binding.Template"> <div class="taskItem"> Id: <span data-win-bind="innerText:id"></span> <br /><br /> Name: <span data-win-bind="innerText:name"></span> </div> </div> <div id="lvTasks" data-win-control="WinJS.UI.ListView" data-win-options="{ itemTemplate: select('#tmplTask'), selectionMode: 'single' }"></div> <form id="frmAdd"> <fieldset> <legend>Add Task</legend> <label>New Task</label> <input id="inputTaskName" required /> <button>Add</button> </fieldset> </form> <button id="btnNuke">Nuke</button> <button id="btnDelete">Delete</button> </body> </html> And here is the JavaScript code for the TaskList app: /// <reference path="//Microsoft.WinJS.1.0.RC/js/base.js" /> /// <reference path="//Microsoft.WinJS.1.0.RC/js/ui.js" /> function init() { WinJS.UI.processAll().done(function () { var lvTasks = document.getElementById("lvTasks").winControl; // Bind the ListView to its data source var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; // Wire-up Add, Delete, Nuke buttons document.getElementById("frmAdd").addEventListener("submit", function (evt) { evt.preventDefault(); tasksDataSource.beginEdits(); tasksDataSource.insertAtEnd(null, { name: document.getElementById("inputTaskName").value }).done(function (newItem) { tasksDataSource.endEdits(); document.getElementById("frmAdd").reset(); lvTasks.ensureVisible(newItem.index); }); }); document.getElementById("btnDelete").addEventListener("click", function () { if (lvTasks.selection.count() == 1) { lvTasks.selection.getItems().done(function (items) { tasksDataSource.remove(items[0].data.id); }); } }); document.getElementById("btnNuke").addEventListener("click", function () { tasksDataSource.nuke(); }); // This method is called to initialize the IndexedDb database function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } }); } document.addEventListener("DOMContentLoaded", init); The IndexedDbDataSource is created and bound to the ListView control with the following two lines of code: var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; The IndexedDbDataSource is created with four parameters: the name of the database to create, the version of the database to create, the name of the object store to create, and a function which contains code to initialize the new database. The upgrade function creates a new object store named tasks with an auto-increment property named id: function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } The Complete Code for the IndexedDbDataSource Here’s the complete code for the IndexedDbDataSource: (function () { /************************************************ * The IndexedDBDataAdapter enables you to work * with a HTML5 IndexedDB database. *************************************************/ var IndexedDbDataAdapter = WinJS.Class.define( function (dbName, dbVersion, objectStoreName, upgrade, error) { this._dbName = dbName; // database name this._dbVersion = dbVersion; // database version this._objectStoreName = objectStoreName; // object store name this._upgrade = upgrade; // database upgrade script this._error = error || function (evt) { console.log(evt.message); }; }, { /******************************************* * IListDataAdapter Interface Methods ********************************************/ getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); }, itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); }, insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); }, setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, /***************************************** * IndexedDbDataSource Method ******************************************/ removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); }, nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); }, /******************************************* * Private Methods ********************************************/ _ensureDbOpen: function () { var that = this; // Try to get cached Db if (that._cachedDb) { return WinJS.Promise.wrap(that._cachedDb); } // Otherwise, open the database return new WinJS.Promise(function (complete, error, progress) { var reqOpen = window.indexedDB.open(that._dbName, that._dbVersion); reqOpen.onerror = function (evt) { error(); }; reqOpen.onupgradeneeded = function (evt) { that._upgrade(evt); that._notificationHandler.invalidateAll(); }; reqOpen.onsuccess = function () { that._cachedDb = reqOpen.result; complete(that._cachedDb); }; }); }, _getObjectStore: function (type) { type = type || "readonly"; var that = this; return new WinJS.Promise(function (complete, error) { that._ensureDbOpen().then(function (db) { var transaction = db.transaction(that._objectStoreName, type); complete(transaction.objectStore(that._objectStoreName)); }); }); }, _get: function (key) { return new WinJS.Promise(function (complete, error) { that._getObjectStore().done(function (store) { var reqGet = store.get(key); reqGet.onerror = that._error; reqGet.onsuccess = function (item) { complete(item); }; }); }); } } ); var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); WinJS.Namespace.define("DataSources", { IndexedDbDataSource: IndexedDbDataSource }); })(); Summary In this blog post, I provided an overview of how you can create a new data source which you can use with the WinJS library. I described how you can create an IndexedDbDataSource which you can use to bind a ListView control to an IndexedDB database. While describing how you can create a custom data source, I explained how you can implement the IListDataAdapter interface. You also learned how to raise notifications — such as a removed or invalidateAll notification — by taking advantage of the methods of the IListDataNotificationHandler interface.

    Read the article

  • Is it possible to simultaneously debug VB6 and a C++ COM dll?

    - by Steve
    I have a VB6 dll that is loaded by a VB6 frontend. This VB6 dll calls a C++ ATL dll via its COM interface. So, I can run from code in VB6 and I can debug in C++ also, however I can't seem to step through the VB6 code and then get into the C++ code. I feel that this should be possible. Currently I am doing the following steps Start VB6 debugging Start C++ debugging. This involves starting the VB6 front end and setting the working directory to the VB6 front end directory using the VS2008 Debugging Properties in the Options. Execute the code and step through the VB6 code to the point where I should be entering the C++ code. I see the loaded symbols window changing in the VS2008 IDE. Now, it looks like it should work, but I never hit any breakpoints in my C++ code. I hit the breakpoints if I don't start the VB6 debugging first.

    Read the article

< Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >