Search Results

Search found 16643 results on 666 pages for 'stackoverflow answer'.

Page 581/666 | < Previous Page | 577 578 579 580 581 582 583 584 585 586 587 588  | Next Page >

  • jQuery: AJAX call isn't updating page

    - by Cortopasta
    Thought I had a simple AJAX call using $.POST(), but apparently my function isn't firing, and nothing is updating :-/ Here is the call: $(".answerVerse ul li").click(function(){ var rank = $(this).removeClass("star_empty star_full star_highlight").attr("class"); var verse_id = $(this).parent().parent().find(".verseId").html(); var answer_id = $(this).parent().parent().find(".answerId").html(); var place = this; $.post("rank.php", { rank: rank, verse_id: verse_id, answer_id: answer_id },function(data){ $(place).parent().removeClass().addClass(data.newVerseRank); for (i=0;i<=5;i++) { $(".answerVerse ul."+i).each(function(){ $(".answerVerse ul."+i+" li."+i).prevAll().andSelf().removeClass("star_empty").addClass("star_full"); }); } }, "json"); }); And here is the PHP (rank.php) that it calls: require_once("dbcon.php"); $user = new user(); $user->updateVerseRank($_POST['verse_id'], $_POST['rank']); $user->getVerse($_POST['verse_id']); $user->getAnswer($_POST['answer_id']; $arr = array ('newVerseRank'=>htmlspecialchars(round($user->verse[3])),'newVerseVotes'=>htmlspecialchars(round($user->verse[4])),'newAnswerRank'=>htmlspecialchars($user->answer[3])); echo json_encode($arr); Why am I not updating the page? I know it's something dumb I'm doing seeing as how this is my first attempt at AJAX and JSON :-/ Just trying to learn

    Read the article

  • Give the mount point of a path

    - by Charles Stewart
    The following, very non-robust shell code will give the mount point of $path: (for i in $(df|cut -c 63-99); do case $path in $i*) echo $i;; esac; done) | tail -n 1 Is there a better way to do this? Postscript This script is really awful, but has the redeeming quality that it Works On My Systems. Note that several mount points may be prefixes of $path. Examples On a Linux system: cas@txtproof:~$ path=/sys/block/hda1 cas@txtproof:~$ for i in $(df -a|cut -c 57-99); do case $path in $i*) echo $i;; esac; done| tail -1 /sys On a Mac osx system cas local$ path=/dev/fd/0 cas local$ for i in $(df -a|cut -c 63-99); do case $path in $i*) echo $i;; esac; done| tail -1 /dev Note the need to vary cut's parameters, because of the way df's output differs: indeed, awk is better. Answer It looks like munging tabular output is the only way within the shell, but df /dev/fd/impossible | tail -1 | awk '{ print $NF}' is a big improvement on what I had. Note two differences in semantics: firstly, df $path insists that $path names an existing file, the script I had above doesn't care; secondly, there are no worries about dereferncing symlinks. It's not difficult to write Python code to do the job.

    Read the article

  • How do I write recursive anonymous functions?

    - by James T Kirk
    In my continued effort to learn scala, I'm working through 'Scala by example' by Odersky and on the chapter on first class functions, the section on anonymous function avoids a situation of recursive anonymous function. I have a solution that seems to work. I'm curious if there is a better answer out there. From the pdf: Code to showcase higher order functions def sum(f: Int => Int, a: Int, b: Int): Int = if (a > b) 0 else f(a) + sum(f, a + 1, b) def id(x: Int): Int = x def square(x: Int): Int = x * x def powerOfTwo(x: Int): Int = if (x == 0) 1 else 2 * powerOfTwo(x-1) def sumInts(a: Int, b: Int): Int = sum(id, a, b) def sumSquares(a: Int, b: Int): Int = sum(square, a, b) def sumPowersOfTwo(a: Int, b: Int): Int = sum(powerOfTwo, a, b) scala> sumPowersOfTwo(2,3) res0: Int = 12 from the pdf: Code to showcase anonymous functions def sum(f: Int => Int, a: Int, b: Int): Int = if (a > b) 0 else f(a) + sum(f, a + 1, b) def sumInts(a: Int, b: Int): Int = sum((x: Int) => x, a, b) def sumSquares(a: Int, b: Int): Int = sum((x: Int) => x * x, a, b) // no sumPowersOfTwo My code: def sumPowersOfTwo(a: Int, b: Int): Int = sum((x: Int) => { def f(y:Int):Int = if (y==0) 1 else 2 * f(y-1); f(x) }, a, b) scala> sumPowersOfTwo(2,3) res0: Int = 12

    Read the article

  • Should I be using Expression Blend to design really dynamic UIs?

    - by Robert Rossney
    My company's product is, at its core, a framework for developing metadata-driven UIs. I don't know how to characterize it less succinctly than that, and hope I won't need to for purposes of this question, but we'll see. I've been trying to come up to speed on WPF, and have been building UI prototypes here and there, and recently I decided to see if I could use Expression Blend to help with the design of these UIs. And I'm pretty mystified at this point. It appears to me as though Expresssion Blend is designed with the expectation that you already know all of the objects that are going to be present in the UI at design time. But our program generates these object dynamically at runtime. For instance, a data row might be presented in a horizontal StackPanel containing alternating TextBlocks (for captions) and TextBoxes (for data fields). The number of these objects depends on metadata about the number of columns in the data row. I can, pretty readily, write code that runs through a metadata record and populates a StackPanel dynamically, setting up the binding of all of the controls to properties in either the data or metadata. (A TextBox's Width might be bound to metadata, while its Text is bound to data.) But I can't even begin to figure out how to do something like this in Expression Blend. I can manually create all these controls, so that I have a set of controls that I can apply styles to and work out the visual design of the app, but it's really a pain to do this. I can write code that goes through my data model and emits XAML for all these controls, I suppose, and then copy and paste it. But I'm going to feel really stupid if it turns out there a way to do this sort of thing in Expression Blend and I've dropped back and punted because I'm too dim to figure out the right way to think of it. Is this enough information for someone to try formulating an answer?

    Read the article

  • Fastest way to perform subset test operation on a large collection of sets with same domain

    - by niktech
    Assume we have trillions of sets stored somewhere. The domain for each of these sets is the same. It is also finite and discrete. So each set may be stored as a bit field (eg: 0000100111...) of a relatively short length (eg: 1024). That is, bit X in the bitfield indicates whether item X (of 1024 possible items) is included in the given set or not. Now, I want to devise a storage structure and an algorithm to efficiently answer the query: what sets in the data store have set Y as a subset. Set Y itself is not present in the data store and is specified at run time. Now the simplest way to solve this would be to AND the bitfield for set Y with bit fields of every set in the data store one by one, picking the ones whose AND result matches Y's bitfield. How can I speed this up? Is there a tree structure (index) or some smart algorithm that would allow me to perform this query without having to AND every stored set's bitfield? Are there databases that already support such operations on large collections of sets?

    Read the article

  • How do I get Facebook Application Login to work

    - by Javaaaa
    I just started making an application for Facebook, however I ran into problem early on. The first step I want people to do is to give permission to access their profile. All over the web are examples of how to do this with: $user_id = $facebook->require_login(); However, this is the way it works using the Old PHP API. I have downloaded and installed the new one in my application folder and it is not working anymore. My question is (and i really have been searching for an answer for a long time) what is the code to do this with the new API? (and related question: is it better to use the old API, or learn to work with the new one when I am just starting making apps right now) I have this code now; <?php // Awesome Facebook Application // // Name: - // require_once 'facebook-php-sdk/src/facebook.php'; // Create our Application instance. $facebook = new Facebook(array( 'appId' => $app_id, 'secret' => $app_secret, 'cookie' => true )); $loginUrl = $facebook->getLoginUrl(array( 'req_perms' => 'email,user_birthday,publish_stream,sms,status_update,user_location' )); echo "<p>hello, <fb:name uid=\"$user_id\" useyou=\"false\" />!</p>"; ?>

    Read the article

  • OpenGL fast texture drawing with vertex buffer objects. Is this the way to do it?

    - by Matthew Mitchell
    Hello. I am making a 2D game with OpenGL. I would like to speed up my texture drawing by using VBOs. Currently I am using the immediate mode. I am generating my own coordinates when I rotate and scale a texture. I also have the functionality of rounding the corners of a texture, using the polygon primitive to draw those. I was thinking, would it be fastest to make a VBO with vertices for the sides of the texture with no offset included so I can then use glViewport, glScale (Or glTranslate? What is the difference and most suitable here?) and glRotate to move the drawing position for my texture. Then I can use the same VBO with no changes to draw the texture each time. I could only change the VBO when I need to add coordinates for the rounded corners. Is that the best way to do this? What things should I look out for while doing it? Is it really fastest to use GL_TRIANGLES instead of GL_QUADS in modern graphics cards? Thank you for any answer.

    Read the article

  • List modification in Python

    - by user2945143
    We are given an algorithm to modify a list of numbers from 1 to 28. There are 5 steps in the algorithm. We have written functions for each step (all correct). We need to write a function that combines all 5 steps. The algorithm modifies the list to get a value. Each time you get a new value, you use the list created by the algorithm from the previous step. This is what we have gotten so far for the code: get_card_at_top_index(insert_top_to_bottom(triple_cut((move_joker_2( move_joker_1(deck)))))) When we run the code to generate the get_card_at_top_index, the first answer is correct. However, the rest are not. Instead of using from the new list, python uses the value that it generated from the last step. What did we do wrong? UPDATE: The other 5 codes passed the tests, they are correct. Code 1 (List) = list1 Code 2 (list1) = list2 Code 3 (list2) = list3 Code 4 (list3) = list4 Code 5 (list4) = list5 we generate a number from 5. We need to run the algorithm again to generate 25 more numbers. We will use list 5 start from step 1

    Read the article

  • Why is my quick sort so slow?

    - by user513075
    Hello, I am practicing writing sorting algorithms as part of some interview preparation, and I am wondering if anybody can help me spot why this quick sort is not very fast? It appears to have the correct runtime complexity, but it is slower than my merge sort by a constant factor of about 2. I would also appreciate any comments that would improve my code that don't necessarily answer the question. Thanks a lot for your help! Please don't hesitate to let me know if I have made any etiquette mistakes. This is my first question here. private class QuickSort implements Sort { @Override public int[] sortItems(int[] ts) { List<Integer> toSort = new ArrayList<Integer>(); for (int i : ts) { toSort.add(i); } toSort = partition(toSort); int[] ret = new int[ts.length]; for (int i = 0; i < toSort.size(); i++) { ret[i] = toSort.get(i); } return ret; } private List<Integer> partition(List<Integer> toSort) { if (toSort.size() <= 1) return toSort; int pivotIndex = myRandom.nextInt(toSort.size()); Integer pivot = toSort.get(pivotIndex); toSort.remove(pivotIndex); List<Integer> left = new ArrayList<Integer>(); List<Integer> right = new ArrayList<Integer>(); for (int i : toSort) { if (i > pivot) right.add(i); else left.add(i); } left = partition(left); right = partition(right); left.add(pivot); left.addAll(right); return left; } }

    Read the article

  • Why is it that an int in C++ that isnt initialized (then used) doesn't return an error?

    - by omizzle
    I am new to C++ (just starting). I come from a Java background and I was trying out the following piece of code that would sum the numbers between 1 and 10 (inclusive) and then print out the sum: /* * File: main.cpp * Author: omarestrella * * Created on June 7, 2010, 8:02 PM */ #include <cstdlib> #include <iostream> using namespace std; int main() { int sum; for(int x = 1; x <= 10; x++) { sum += x; } cout << "The sum is: " << sum << endl; return 0; } When I ran it it kept printing 32822 for the sum. I knew the answer was supposed to be 55 and realized that its print the max value for a short (32767) plus 55. Changing int sum; to int sum = 0; would work (as it should, since the variable needs to be initialized!). Why does this behavior happen, though? Why doesnt the compiler warn you about something like this? I know Java screams at you when something isnt initialized. Thank you.

    Read the article

  • How can you change the font color of a theme-enabled control?

    - by Edouard Westphal
    Yes, this is again this question: How can I change the font color of a TCheckBox (or any handled control) with Delphi7-Delphi2007 on a themes enabled application? After reading a lot on the internet and on this site, I found 4 kinds of answer: and Most populare (even from QC): You can't, it's designed like that by Microsoft. Create a component that let you draw it like you want. Buy expensive component set that draws like you want. Do not use themes. OK, but I am still unhappy with that. Giving a user colored feedback for the status of a property/data he has on a form, seems legitimate to me. Then I just installed the MSVC# 2008 Express edition, and what a surprise, they can change the color of the font (property ForeColor of the check box) Then what? It does not seem to be a "it's designed like that, by Microsoft." then now the question again: How can I change the font color of a TCheckBox (or any handled control) with Delphi 7 through Delphi 2007 on a theme-enabled application?

    Read the article

  • Get the src part of a string [duplicate]

    - by Kay Lakeman
    This question already has an answer here: Grabbing the href attribute of an A element 7 answers First post ever here, and i really hope you can help. I use a database where a large piece of html is stored, now i just need the src part of the image tag. I already found a thread, but i just doesn't do the trick. My code: Original string: <p><img alt=\"\" src=\"http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png\" style=\"width: 80px; height: 160px;\" /></p> How i start: $image = strip_tags($row['information'], '<img>'); echo stripslashes($image); This returns: <img alt="" src="http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png" style="width: 80px; height: 160px;" /> Next step: extract the src part: preg_match('/< *img[^>]*src *= *["\']?([^"\']*)/i', $image, $matches); echo $matches ; This last echo returns: Array What is going wrong? Thanks in advance for your anwser.

    Read the article

  • How to catch unintentional function interpositioning?

    - by SiegeX
    Reading through my book Expert C Programming, I came across the chapter on function interpositioning and how it can lead to some serious hard to find bugs if done unintentionally. The example given in the book is the following: my_source.c mktemp() { ... } main() { mktemp(); getwd(); } libc mktemp(){ ... } getwd(){ ...; mktemp(); ... } According to the book, what happens in main() is that mktemp() (a standard C library function) is interposed by the implementation in my_source.c. Although having main() call my implementation of mktemp() is intended behavior, having getwd() (another C library function) also call my implementation of mktemp() is not. Apparently, this example was a real life bug that existed in SunOS 4.0.3's version of lpr. The book goes on to explain the fix was to add the keyword static to the definition of mktemp() in my_source.c; although changing the name altogether should have fixed this problem as well. This chapter leaves me with some unresolved questions that I hope you guys could answer: Does GCC have a way to warn about function interposition? We certainly don't ever intend on this happening and I'd like to know about it if it does. Should our software group adopt the practice of putting the keyword static in front of all functions that we don't want to be exposed? Can interposition happen with functions introduced by static libraries? Thanks for the help. EDIT I should note that my question is not just aimed at interposing over standard C library functions, but also functions contained in other libraries, perhaps 3rd party, perhaps ones created in-house. Essentially, I want to catch any instance of interpositioning regardless of where the interposed function resides.

    Read the article

  • What's so bad about building XML with string concatenation?

    - by wsanville
    In the thread What’s your favorite “programmer ignorance” pet peeve?, the following answer appears, with a large amount of upvotes: Programmers who build XML using string concatenation. My question is, why is building XML via string concatenation (such as a StringBuilder in C#) bad? I've done this several times in the past, as it's sometimes the quickest way for me to get from point A to point B when to comes to the data structures/objects I'm working with. So far, I have come up with a few reasons why this isn't the greatest approach, but is there something I'm overlooking? Why should this be avoided? Probably the biggest reason I can think of is you need to escape your strings manually, and most programmers will forget this. It will work great for them when they test it, but then "randomly" their apps will fail when someone throws an & symbol in their input somewhere. Ok, I'll buy this, but it's really easy to prevent the problem (SecurityElement.Escape to name one). When I do this, I usually omit the XML declaration (i.e. <?xml version="1.0"?>). Is this harmful? Performance penalties? If you stick with proper string concatenation (i.e. StringBuilder), is this anything to be concerned about? Presumably, a class like XmlWriter will also need to do a bit of string manipulation... There are more elegant ways of generating XML, such as using XmlSerializer to automatically serialize/deserialize your classes. Ok sure, I agree. C# has a ton of useful classes for this, but sometimes I don't want to make a class for something really quick, like writing out a log file or something. Is this just me being lazy? If I am doing something "real" this is my preferred approach for dealing w/ XML.

    Read the article

  • java.lang.ClassNotFoundException in Netbeans. 5 hours to fix

    - by user1304281
    Hi I've got to submit an interpreter assignment tonight and all of a sudden it stopped working! It was working yesterday but now when I try to create a class instance at runtime I get classnotfoundexception. My project has no libraries or dependencies, I've written everything myself. I've googled around and it seems to be an issue with classpath but I've had no luck fooling with the project properties on netbeans. Here's some code: package interpreter; import interpreter.bytecode.ByteCode; import java.io.*; import java.lang.reflect.*; class ByteCodeLoader { //.... String codeClass = CodeTable.CodeTable.get(args[0]); ByteCode bytecode = (ByteCode)(Class.forName("interpreter.bytecode."+codeClass).newInstance()); //this throws exception } all of my ByteCodes are contained within a subpackage of interpreter called interpreter.bytecode. I'll be watching this thread so I can answer/clarify any questions immediately. Thanks for your time!

    Read the article

  • Does new JUnit 4.8 @Category render test suites almost obsolete?

    - by grigory
    Given question 'How to run all tests belonging to a certain Category?' and the answer would the following approach be better for test organization? define master test suite that contains all tests (e.g. using ClasspathSuite) design sufficient set of JUnit categories (sufficient means that every desirable collection of sets is identifiable using one or more categories) define targeted test suites based on master test suite and set of categories For example: identify categories for speed (slow, fast), dependencies (mock, database, integration), function (), domain ( demand that each test is properly qualified (tagged) with relevant set of categories. create master test suite using ClasspathSuite (all tests found in classpath) create targeted suites by qualifying master test suite with categories, e.g. mock test suite, fast database test suite, slow integration for domain X test suite, etc. My question is more like soliciting approval rate for such approach vs. classic test suite approach. One unbeatable benefit is that every new test is immediately contained by relevant suites with no suite maintenance. One concern is proper categorization of each test.

    Read the article

  • Why would the same web form control render different "onclick" logic based on the page structure?

    - by zk812
    It was hard to title this question. :) I have a user control that is used to display a list of lookup items in my database and a delete button for each item (Editor User Control below). The delete button has an onClientClick event used to display a confirmation dialog in JavaScript. On page one, the confirmation pops up and functions correctly. The overall structure is: Master Page Page Editor User Control List of items with delete button On page two, the confirmation pops up but regardless of the answer, the page posts back anyway. The structure of this page is: Master Page Page User Control Editor User Control List of items with delete button For some reason, this makes a difference in how the delete button is rendered. Page one: <input type="image" name="ctl00...RequestTypesDataList$ctl01$ctl01" src="Images/Disable.png" alt="Delete" onclick="return ProcessDeleteCommand(1);" /> Page two: <input type="image" name="ctl00...RequestTypesDataList$ctl07$ctl01" src="Images/Disable.png" alt="Delete" onclick="return ProcessDeleteCommand(2);WebForm_DoPostBackWithOptions(new WebForm_PostBackOptions(&quot;ctl00$ContentPlaceHolder1$RequestCreator1$RequestTypeEditor1$RequestTypesDataList$ctl07$ctl01&quot;, &quot;&quot;, true, &quot;&quot;, &quot;&quot;, false, false))" /> Does anyone know why page two renders WebForm_DoPostBackWithOptions after my JS check? It's causing the postback regardless of the confirmation choice.

    Read the article

  • What's the correct place to share application logic in CakePHP?

    - by Pichan
    I guess simple answer to the question would be a component. Although I agree, I feel weird having to write a component for something so specific. For example, let's say I have a table of users. When a user is created, it should form a chain reaction of events, initiating different kinds of data related to the user all around the database. I figured it would be best to avoid directly manipulating the database from different controllers and instead pack all that neatly in a method. However since some logic needs to be accesed separately, I really can't have the whole package in a single method. Instead I thought it would be logical to break it up to smaller pieces(like $userModelOrController->createNew() and $candyStorageModelOrController->createNew()) that only interact with their respective database table. Now, if the logic is put to the model, it works great until I need to use other models. Of course it's possible, but when compared to loading models in a controller, it's not that simple. It's like a Cake developer telling me "Sure, it's possible if you want to do it that way but that's not how I would do it". Then, if the logic is put to the controller, I can access other models really easy through $this->loadModel(), but that brings me back to the previously explained situation since I need to be able to continue the chain reaction indefinitely. Accessing other controllers from a controller is possible, but again there doesn't seem to be any direct way of doing so, so I'm guessing I'm still not doing it right. By using a component this problem could be solved easily, since components are available to every controller I want. But like I wrote at the beginning, it feels awkward to create a component specifically for this one task. To me, components seem more like packages of extra functionality(like the core components) and not something to share controller-specific logic. Since I'm new to this whole MVC thing, I could've completely misunderstood the concept. Once again, I would be thankful if someone pointed me to the right direction :)

    Read the article

  • What OpenGL functions are not GPU accelerated?

    - by Xavier Ho
    I was shocked when I read this (from the OpenGL wiki): glTranslate, glRotate, glScale Are these hardware accelerated? No, there are no known GPUs that execute this. The driver computes the matrix on the CPU and uploads it to the GPU. All the other matrix operations are done on the CPU as well : glPushMatrix, glPopMatrix, glLoadIdentity, glFrustum, glOrtho. This is the reason why these functions are considered deprecated in GL 3.0. You should have your own math library, build your own matrix, upload your matrix to the shader. For a very, very long time I thought most of the OpenGL functions use the GPU to do computation. I'm not sure if this is a common misconception, but after a while of thinking, this makes sense. Old OpenGL functions (2.x and older) are really not suitable for real-world applications, due to too many state switches. This makes me realise that, possibly, many OpenGL functions do not use the GPU at all. So, the question is: Which OpenGL function calls don't use the GPU? I believe knowing the answer to the above question would help me become a better programmer with OpenGL. Please do share some of your insights.

    Read the article

  • How to get the set of beans that are to be created in Spring?

    - by cyborg
    So here's the scenario: I have a Spring XML configuration with some lazy-beans, some not lazy-beans and some beans that depend on other beans. Eventually Spring will resolve all this so that only the beans that are meant to be created are created. The question: how can I programmatically tell what this set is? When I use context.getBean(name) that initializes the bean. BeanDefinition.isLazyInit() will only tell me how I defined the bean. Any other ideas? ETA: In DefaultListableBeanFactory: public void preInstantiateSingletons() throws BeansException { if (this.logger.isInfoEnabled()) { this.logger.info("Pre-instantiating singletons in " + this); } synchronized (this.beanDefinitionMap) { for (Iterator it = this.beanDefinitionNames.iterator(); it.hasNext();) { String beanName = (String) it.next(); RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName); if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) { if (isFactoryBean(beanName)) { FactoryBean factory = (FactoryBean) getBean(FACTORY_BEAN_PREFIX + beanName); if (factory instanceof SmartFactoryBean && ((SmartFactoryBean) factory).isEagerInit()) { getBean(beanName); } } else { getBean(beanName); } } } } } The set of instantiable beans is initialized. When initializing this set any beans not in this set referenced by this set will also be created. From looking through the source it does not look like there's going to be any easy way to answer my question.

    Read the article

  • Modify columns in a data frame in R more cleanly - maybe using with() or apply()?

    - by Mittenchops
    I understand the answer in R to repetitive things is usually "apply()" rather than loop. Is there a better R-design pattern for a nasty bit of code I create frequently? So, pulling tabular data from HTML, I usually need to change the data type, and end up running something like this, to convert the first column to date format (from decimal), and columns 2-4 from character strings with comma thousand separators like "2,400,000" to numeric "2400000." X[,1] <- decYY2YY(as.numeric(X[,1])) X[,2] <- as.numeric(gsub(",", "", X[,2])) X[,3] <- as.numeric(gsub(",", "", X[,3])) X[,4] <- as.numeric(gsub(",", "", X[,4])) I don't like that I have X[,number] repeated on both the left and ride sides here, or that I have basically the same statement repeated for 2-4. Is there a very R-style way of making X[,2] less repetitive but still loop-free? Something that sort of says "apply this to columns 2,3,4---a function that reassigns the current column to a modified version in place?" I don't want to create a whole, repeatable cleaning function, really, just a quick anonymous function that does this with less repetition.

    Read the article

  • PyGTK: Manually render an existing widget at a given Rectangle? (TextView in a custom CellRenderer)

    - by NicDumZ
    Hello! I am trying to draw a TextView into the cell of a TreeView. (Why? I would like to have custom tags on text, so they can be clickable and trigger different actions/popup menus depending on where user clicks). I have been trying to write a customized CellRenderer for this purpose, but so far I failed because I find it extremely difficult to find generic documentation on rendering design in gtk. More than an answer at the specific question (that might be hard/not doable, and I'm not expecting you to do everything for me), I am first looking for documentation on how a widget is rendered, to understand how one is supposed to implement a CellRenderer. Can you share any link that explains, either for gtk or for pygtk, the rendering mechanism? More specifically: size allocation mechanism (should I say protocol?). I understand that a window has a defined size, and then queries its children, saying "my size is w x h, what would be your ideal size, buddy?", and then sometimes shrinks children when all children cant fit together at their ideal sizes. Any specific documentation on that, and on particular on when this happens during rendering? How are rendered "builtin" widgets? What kind of methods do they call on Widget base class? On the parent Window? When? Do they use pango.Layout? can you manually draw a TextView onto a pango.Layout object? This link gives an interesting example showing how you can draw content in a pango.Layout object and use it in a CellRenderer. I guess that I could adapt it if only I understood how TextView widget are rendered. Or perhaps, to put it more simply: given an existing widget instance, how does one render it at a specific gdk.Rectangle? Thanks a lot.

    Read the article

  • Best practices for (over)using Azure queues

    - by John
    Hi, I'm in the early phases of designing an Azure-based application. One of the things that attracts me to Azure is the scalability, given the variability of the demand I'm likely to expect. As such I'm trying to keep things loosely coupled so I can add instances when I need to. The recommendations I've seen for architecting an application for Azure include keeping web role logic to a minimum, and having processing done in worker roles, using queues to communicate and some sort of back-end store like SQL Azure or Azure Tables. This seems like a good idea to me as I can scale up either or both parts of the application without any issue. However I'm curious if there are any best practices (or if anyone has any experiences) for when it's best to just have the web role talk directly to the data store vs. sending data by the queue? I'm thinking of the case where I have a simple insert to do from the web role - while I could set this up as a message, send it on the queue, and have a worker role pick it up and do the insert, it seems like a lot of double-handling. However I also appreciate that it may be the case that this is better in the long run, in case the web role gets overwhelmed or more complex logic ends up being required for the insert. I realise this might be a case where the answer is "it depends entirely on the situation, check your perf metrics" - but if anyone has any thoughts I'd be very appreciative! Thanks John

    Read the article

  • Ruby on Rails : How can i display data for the current view from a different table

    - by krishkule
    This might be a easy-to-answer question, but its a pain in the bum for me.... So... I have two tables - Chords - |id|chord|name|rating|artist_id| Artists - |id|artist| (the relations : chords : belongs_to :artist artists : has_many :chords ) And in the index page for "chords" i want to display chord,name,rating from Chords table AND artist from the Artists table this is the code for the chrod's index.html.erb : <table border="1"> <%@chords.each do |chord|%> <tr> <td><%=chord.artist.artist%></td> <td><%= link_to chord.name, chord %></td> <td><%=chord.rating%></td> <td><%= chord.created_at %></td> </tr> <%end%> </table> The error message is : undefined method `artist' for nil:NilClass Actually, at first it worked, but when i started to create the "new.html.erb" page and the create,new controllers, it stopped working - thats why this is so confusing for me! I will be glad to hear any critique and suggestions! Thank you

    Read the article

  • Initializing static pointer in templated class.

    - by Anthony
    This is difficult for me to formulate in a Google query (at least one that gives me what I'm looking for) so I've had some trouble finding an answer. I'm sure I'm not the first to ask though. Consider a class like so: template < class T > class MyClass { private: static T staticObject; static T * staticPointerObject; }; ... template < class T > T MyClass<T>::staticObject; // <-- works ... template < class T > T * MyClass<T>::staticPointerObject = NULL; // <-- cannot find symbol staticPointerObject. I am having trouble figuring out why I cannot successfully create that pointer object. Edit: The above code is all specified in the header, and the issue I mentioned is an error in the link step, so it is not finding the specific symbol.

    Read the article

< Previous Page | 577 578 579 580 581 582 583 584 585 586 587 588  | Next Page >