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  • How to debug JBoss out of memory problem?

    - by user561733
    Hello, I am trying to debug a JBoss out of memory problem. When JBoss starts up and runs for a while, it seems to use memory as intended by the startup configuration. However, it seems that when some unknown user action is taken (or the log file grows to a certain size) using the sole web application JBoss is serving up, memory increases dramatically and JBoss freezes. When JBoss freezes, it is difficult to kill the process or do anything because of low memory. When the process is finally killed via a -9 argument and the server is restarted, the log file is very small and only contains outputs from the startup of the newly started process and not any information on why the memory increased so much. This is why it is so hard to debug: server.log does not have information from the killed process. The log is set to grow to 2 GB and the log file for the new process is only about 300 Kb though it grows properly during normal memory circumstances. This is information on the JBoss configuration: JBoss (MX MicroKernel) 4.0.3 JDK 1.6.0 update 22 PermSize=512m MaxPermSize=512m Xms=1024m Xmx=6144m This is basic info on the system: Operating system: CentOS Linux 5.5 Kernel and CPU: Linux 2.6.18-194.26.1.el5 on x86_64 Processor information: Intel(R) Xeon(R) CPU E5420 @ 2.50GHz, 8 cores This is good example information on the system during normal pre-freeze conditions a few minutes after the jboss service startup: Running processes: 183 CPU load averages: 0.16 (1 min) 0.06 (5 mins) 0.09 (15 mins) CPU usage: 0% user, 0% kernel, 1% IO, 99% idle Real memory: 17.38 GB total, 2.46 GB used Virtual memory: 19.59 GB total, 0 bytes used Local disk space: 113.37 GB total, 11.89 GB used When JBoss freezes, system information looks like this: Running processes: 225 CPU load averages: 4.66 (1 min) 1.84 (5 mins) 0.93 (15 mins) CPU usage: 0% user, 12% kernel, 73% IO, 15% idle Real memory: 17.38 GB total, 17.18 GB used Virtual memory: 19.59 GB total, 706.29 MB used Local disk space: 113.37 GB total, 11.89 GB used

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  • Any guidelines for handling the Headset and Bluetooth AVRC transport controls in Android 2.2

    - by StefanK
    I am trying to figure out what is the correct (new) approach for handling the Intent.ACTION_MEDIA_BUTTON in Froyo. In pre 2.2 days we had to register a BroadcastReceiver (either permanently or at run-time) and the Media Button events would arrive, as long as no other application intercepts them and aborts the broadcast. Froyo seems to still somewhat support that model (at least for the wired headset), but it also introduces the registerMediaButtonEventReceiver, and unregisterMediaButtonEventReceiver methods that seem to control the "transport focus" between applications. During my experiments, using registerMediaButtonEventReceiver does cause both the bluetooth and the wired headset button presses to be routed to the application's broadcast receiver (the app gets the "transport focus"), but it looks like any change in the audio routing (for example unplugging the headset) shits the focus back to the default media player. What is the logic behind the implementation in Android 2.2? What is correct way to handle transport controls? Do we have to detect the change in the audio routing and try to re-gain the focus? This is an issue that any 3rd party media player on the Android platform has to deal with, so I hope that somebody (probably a Google Engineer) can provide some guidelines that we can all follow. Having a standard approach may make headset button controls a bit more predictable for the end users. Stefan

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  • VisualSVN How to roll back the revision number ?

    - by Ita
    The company I work in has suffered a major server failure. During this failure the SVN Repository was lost. But there is still hope ! We have an old backup of the repository which I've managed to successfully restore using VisualSVN. The problem I'm facing now is that I can't update / commit pre-failure checkedout folders. The reason for this problem is that for instance: a local folder has a revision number of 2361, while the repository itself holds a revision number of 2290, which is older. Is there a way to deal with this issue ? Can I some how change the revision numbers on either the local copy or the server copy? A few points: I'm using TortoiseSVN 1.6.6. I can checkout folders from the repo and the connection is active. I've picked one of my folders and used the Relocate option on it. This helped me see that there is something wrong with the revision number I've experimented a bit with the merge option but this lead me now where special. (I'm open for suggestions ) Thank you for your time, Ita

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  • find on page neighbouring siblings jquery?

    - by Stefan
    ok i've been searching for an answer to this (if there even is one) with no luck i have a succession of div elements as shown in the pic bellow: http://i61.photobucket.com/albums/h46/DrAcOliCh_2006/untitled-1.jpg?t=1300520458 the blue background is the absolute parent of the orange divs which are also siblings the DOM is not quite organized according to how the orange elements appear on the page because they are all draggable (i used jquery UI) and i moved them around inside the parent, yet, as some know, the DOM doesn't get reorganized when i move draggable elements around, so basically the siblings structure remains the same inside the DOM what i kinda need (again if that is even possible) is to determine the immediate on page neighbouring siblings of eachother; in other words, say we take that "FlashBanner" element which, on page, has the "Logo", the "Search" and the "ShoppingBasket" elements as immediate top siblings and the "Categories" and "Content" elements as immediate bottom siblings (and no left or right siblings) i have a manual solution to this, that is to pre-specify the on page neighbouring siblings for each element through a series of form fields and stuff (another story and another wall of text to explain), but that is not important atm as i want to know if it can be done automatically (i.e tell jquery to find them for me) appreciate any help, even an "it can't be done automatically", and thank you for your time hope this doesn't sound to ambiguous (or silly for that matter) and why i need to do that don't ask :P wall of text to explain cheers :)

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  • Best solution for __autoload

    - by tpk
    As our PHP5 OO application grew (in both size and traffic), we decided to revisit the __autoload() strategy. We always name the file by the class definition it contains, so class Customer would be contained within Customer.php. We used to list the directories in which a file can potentially exist, until the right .php file was found. This is quite inefficient, because you're potentially going through a number of directories which you don't need to, and doing so on every request (thus, making loads of stat() calls). Solutions that come to my mind... -use a naming convention that dictates the directory name (similar to PEAR). Disadvantages: doesn't scale too great, resulting in horrible class names. -come up with some kind of pre-built array of the locations (propel does this for its __autoload). Disadvantage: requires a rebuild before any deploy of new code. -build the array "on the fly" and cache it. This seems to be the best solution, as it allows for any class names and directory structure you want, and is fully flexible in that new files just get added to the list. The concerns are: where to store it and what about deleted/moved files. For storage we chose APC, as it doesn't have the disk I/O overhead. With regards to file deletes, it doesn't matter, as you probably don't wanna require them anywhere anyway. As to moves... that's unresolved (we ignore it as historically it didn't happen very often for us). Any other solutions?

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  • Why doesn't this CompiledQuery give a performance improvement?

    - by Grammarian
    I am trying to speed up an often used query. Using a CompiledQuery seemed to be the answer. But when I tried the compiled version, there was no difference in performance between the compiled and non-compiled versions. Can someone please tell me why using Queries.FindTradeByTradeTagCompiled is not faster than using Queries.FindTradeByTradeTag? static class Queries { // Pre-compiled query, as per http://msdn.microsoft.com/en-us/library/bb896297 private static readonly Func<MyEntities, int, IQueryable<Trade>> mCompiledFindTradeQuery = CompiledQuery.Compile<MyEntities, int, IQueryable<Trade>>( (entities, tag) => from trade in entities.TradeSet where trade.trade_tag == tag select trade); public static Trade FindTradeByTradeTagCompiled(MyEntities entities, int tag) { IQueryable<Trade> tradeQuery = mCompiledFindTradeQuery(entities, tag); return tradeQuery.FirstOrDefault(); } public static Trade FindTradeByTradeTag(MyEntities entities, int tag) { IQueryable<Trade> tradeQuery = from trade in entities.TradeSet where trade.trade_tag == tag select trade; return tradeQuery.FirstOrDefault(); } }

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  • custom *arbitrary* TemplateField definitions

    - by end-user
    I'm building a GridView on the fly, and I'd like to pre-define the TemplateFields to be included ondemand. So, what I'd like to do is have a declarative file that defines how the different templates look for a specific column. Like: <asp:TemplateField> <HeaderTemplate> this is a text column </HeaderTemplate> <ItemTemplate> data goes here </ItemTemplate> <EditItemTemplate> <asp:TextBox Text="databindhere" /> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField> <HeaderTemplate> this is a bool column </HeaderTemplate> <ItemTemplate> if(true) "yes" else "no" </ItemTemplate> <EditItemTemplate> <asp:CheckBox Checked="databindme" /> </EditItemTemplate> </asp:TemplateField> So, if my query had a text and two bool fields, I could push the appropriate TemplateFields in the the Columns property as needed. (I hope I'm making sense here) So, how would I go about creating declarative files for the above definitions? And then, how would I reference those definitions programmatically?

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  • Skip subdirectory in python import

    - by jstaab
    Ok, so I'm trying to change this: app/ - lib.py - models.py - blah.py Into this: app/ - __init__.py - lib.py - models/ - __init__.py - user.py - account.py - banana.py - blah.py And still be able to import my models using from app.models import User rather than having to change it to from app.models.user import User all over the place. Basically, I want everything to treat the package as a single module, but be able to navigate the code in separate files for development ease. The reason I can't do something like add for file in __all__: from file import * into init.py is I have circular references between the model files. A fix I don't want is to import those models from within the functions that use them. But that's super ugly. Let me give you an example: user.py ... from app.models import Banana ... banana.py ... from app.models import User ... I wrote a quick pre-processing script that grabs all the files, re-writes them to put imports at the top, and puts it into models.py, but that's hardly an improvement, since now my stack traces don't show the line number I actually need to change. Any ideas? I always though init was probably magical but now that I dig into it, I can't find anything that lets me provide myself this really simple convenience.

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  • Objective-C Definedness

    - by Dan Ray
    This is an agonizingly rookie question, but here I am learning a new language and framework, and I'm trying to answer the question "What is Truth?" as pertains to Obj-C. I'm trying to lazy-load images across the network. I have a data class called Event that has properties including: @property (nonatomic, retain) UIImage image; @property (nonatomic, retain) UIImage thumbnail; in my AppDelegate, I fetch up a bunch of data about my events (this is an app that shows local arts event listings), and pre-sets each event.image to my default "no-image.png". Then in the UITableViewController where I view these things, I do: if (thisEvent.image == NULL) { NSLog(@"Going for this item's image"); UIImage *tempImage = [UIImage imageWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString: [NSString stringWithFormat: @"http://www.mysite.com/content_elements/%@_image_1.jpg", thisEvent.guid]]]]; thisEvent.image = tempImage; } We never get that NSLog call. Testing thisEvent.image for NULLness isn't the thing. I've tried == nil as well, but that also doesn't work.

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  • AppleScript: open frontmost file with another application

    - by jacobianism
    I'd like to write an AppleScript program to do the following (Automator would be fine too): I want to open the current active TextMate file (possibly there are several tabs open and other windows) with the application Transmit 2. (This will upload the file over FTP using Transmit's DockSend feature.) Here I've used a specific application (TextMate) but ideally I'd like it to work for any file currently active in any application. Ultimately I will assign a keyboard shortcut to run it. Here's what I have so far: tell application (path to frontmost application as text) set p to path of document 1 end tell tell application "Finder" open POSIX file p using "Transmit 2" end tell I've tried many variants of this and nothing works. EDIT: I have found this page: http://wiki.macromates.com/Main/Howtos and someone has made exactly the script I'm looking for: tell application "Transmit" to open POSIX file "$TM_FILEPATH" This is for Transmit [not 2] and I think for TextMate pre v2. I get the error (when using Transmit 2): Transmit 2 got an error: AppleEvent handler failed. One of the updates to v2 has broken it (not sure which one).

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  • how can i redirect page while download box appears?

    - by Ronnie Chester Lynwood
    Now I got this code; <?php $file = "pain.png"; if (file_exists($file)) { header('Content-Description: File Transfer'); header('Content-Type: application/octet-stream'); header('Content-Disposition: attachment; filename='.basename($file)); header('Content-Transfer-Encoding: binary'); header('Expires: 0'); header('Cache-Control: must-revalidate, post-check=0, pre-check=0'); header('Pragma: public'); header('Content-Length: ' . filesize($file)); ob_clean(); flush(); readfile($file); exit; } ?> This code appears a download box. But I want to redirect this page to "Thank You" page while download box still here. How can i do this? Thanks...

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  • What's the best practice for handling system-specific information under version control?

    - by Joe
    I'm new to version control, so I apologize if there is a well-known solution to this. For this problem in particular, I'm using git, but I'm curious about how to deal with this for all version control systems. I'm developing a web application on a development server. I have defined the absolute path name to the web application (not the document root) in two places. On the production server, this path is different. I'm confused about how to deal with this. I could either: Reconfigure the development server to share the same path as the production Edit the two occurrences each time production is updated. I don't like #1 because I'd rather keep the application flexible for any future changes. I don't like #2 because if I start developing on a second development server with a third path, I would have to change this for every commit and update. What is the best way to handle this? I thought of: Using custom keywords and variable expansion (such as setting the property $PATH$ in the version control properties and having it expanded in all the files). Git doesn't support this because it would be a huge performance hit. Using post-update and pre-commit hooks. Possibly the likely solution for git, but every time I looked at the status, it would report the two files as being changed. Not really clean. Pulling the path from a config file outside of version control. Then I would have to have the config file in the same location on all servers. Might as well just have the same path to begin with. Is there an easy way to deal with this? Am I over thinking it?

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  • How to avoid the linebreak inside a word (Static Layout

    - by Addev
    I'm trying to make a text as big as I can making it fit a Rect. basically I use a StaticLayout for pre-calculate the text size and make it fit the Rect's height: // Since the width is fixed for the StaticLayout it should only fit the height while (currentHeight>Rect.getHeight()){ size-=2; } textPaint.setTextSize(size); The problem is that if the Rect is very high, the exit condition is reached but breaking the words (see the capture). Is there a way for avoid this? Goal: Actual: Current code: textSize=MAX_TEXT_SIZE do { if (textSize < mMinTextSize) { Log.i(TAG, "Min reached"); textSize = mMinTextSize; textPaint.setTextSize(textSize); fits = true; } else { textPaint.setTextSize(textSize); StaticLayout layout = new StaticLayout(text, textPaint, targetWidth, Alignment.ALIGN_NORMAL, 1.0, 0, true); layout.draw(canvas); float heightRatio= (float) layout.getHeight() / (float) targetHeight; boolean fitsHeight = heightRatio<= 1f; if (fitsHeight) { fits = true; } else { textSize -= 2; } } Log.i(TAG, "textSize=" + textSize + " fits=" + fits); } while (!fits); thanks

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  • Why would one want to use the public constructors on Boolean and similar immutable classes?

    - by Robert J. Walker
    (For the purposes of this question, let us assume that one is intentionally not using auto(un)boxing, either because one is writing pre-Java 1.5 code, or because one feels that autounboxing makes it too easy to create NullPointerExceptions.) Take Boolean, for example. The documentation for the Boolean(boolean) constructor says: Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory valueOf(boolean) is generally a better choice. It is likely to yield significantly better space and time performance. My question is, why would you ever want to get a new instance in the first place? It seems like things would be simpler if constructors like that were private. For example, if they were, you could write this with no danger (even if myBoolean were null): if (myBoolean == Boolean.TRUE) It'd be safe because all true Booleans would be references to Boolean.TRUE and all false Booleans would be references to Boolean.FALSE. But because the constructors are public, someone may have used them, which means that you have to write this instead: if (Boolean.TRUE.equals(myBoolean)) But where it really gets bad is when you want to check two Booleans for equality. Something like this: if (myBooleanA == myBooleanB) ...becomes this: if ( (myBooleanA == null && myBooleanB == null) || (myBooleanA == null && myBooleanA.equals(myBooleanB)) ) I can't think of any reason to have separate instances of these objects which is more compelling than not having to do the nonsense above. What say you?

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  • What are your Programming Falacies/Myths?

    - by pms1969
    I recently started a new job and as is typical of all jobs, if you've left, you get blamed for everything. Not long after I started there was a change required for an app (web based) that we maintain, and it was quickly pointed out that the actual code for this site had been lost a long time ago, and the only changes we could make to the it were ones that required changes to mark-up [it was a pre-compiled site]. Being new, I needed a little help finding my way around the code, and enlisted the services of one of my colleagues. Made my changes, and then re-enlisted his help to deploy it. While prepping for the deployment (getting the app on the QA server) we discovered that there were actually 2 different, very similarly named, folders in our source repository. It transpired that for the last year or so, mark-up changes had been made to the site directly, and these were the only differences with the code in the slightly incorrectly named folder in source control. So we did have all the code, and can now properly support the site. This put me in mind of a trick we played on a junior programmer once in a previous job, where we told him he couldn't/shouldn't do a certain thing in code as this would likely bring the server to it's knees and cost the company thousands of pounds (a gag that last months :-). And another one in the first programming job I took on - the batch commission run was just going to crash once a month and there was nothing to be done about it, causing a call out, and call out compensation for the on-call guy (a bug I fixed as soon as I became the on-call guy - 2am call outs don't work for me). So I was wondering... What other programming fallacies/myths are out there that are worth sharing?

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  • PHP loop through multidimensional array and change values

    - by stevenpepe
    I have a multidimensional array below and I want to loop through it and change the value of [menu_cats] from a number to a string, which is being pulled from a database selection. Is this possible? The name of the array is 'result'. Array ( [0] => Array ( [0] => Array ( [menu_cats] => 1 [item] => Introduction [link] => needs ) [1] => Array ( [menu_cats] => 1 [item] => Needs Assessment [link] => needs/needs.php ) ) [1] => Array ( [0] => Array ( [menu_cats] => 2 [item] => Introduction [link] => knowledge ) [1] => Array ( [menu_cats] => 2 [item] => Administer Knowledge Pre-Test [link] => knowledge/pre_test.php ) ) )

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  • Creating UIButtons

    - by Ralphonzo
    During loadView I am creating 20 UIButtons that I would like to change the title text of depending on the state of a UIPageControl. I have a pre-save plist that is loaded into a NSArray called arrChars on the event of the current page changing, I set the buttons titles to their relevant text title from the array. The code that does this is: for (int i = 1; i < (ButtonsPerPage + 1); i++) { UIButton *uButton = (UIButton *)[self.view viewWithTag:i]; if(iPage == 1) { iArrPos = (i - 1); } else { iArrPos = (iPage * ButtonsPerPage) + (i - 1); } [uButton setAlpha:0]; NSLog(@"Trying: %d of %d", iArrPos, [self.arrChars count]); if (iArrPos >= [self.arrChars count]) { [uButton setTitle: @"" forState: UIControlStateNormal]; } else { NSString *value = [[NSString alloc] initWithFormat:@"%@", [self.arrChars objectAtIndex:iArrPos]]; NSLog(@"%@", value); [uButton setTitle: [[NSString stringWithFormat:@"%@", value] forState: UIControlStateNormal]; [value release]; //////Have tried: //////[uButton setTitle: value forState: UIControlStateNormal]; //////Have also tried: //////[uButton setTitle: [self.arrChars objectAtIndex:iArrPos] forState: UIControlStateNormal]; //////Have also also tried: //////[uButton setTitle: [[self.arrChars objectAtIndex:iArrPos] autorelease] forState: UIControlStateNormal]; } [uButton setAlpha:1]; } When setting the Title of a button it does not appear to be autoreleasing the previous title and the allocation goes up and up. What am I doing wrong? I have been told before that tracking things by allocations is a bad way to chase leaks because as far as I can see, the object is not leaking in Instruments but my total living allocations continue to climb until I get a memory warning. If there is a better way to track there I would love to know.

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  • Passing C++ object to C++ code through Python?

    - by cornail
    Hi all, I have written some physics simulation code in C++ and parsing the input text files is a bottleneck of it. As one of the input parameters, the user has to specify a math function which will be evaluated many times at run-time. The C++ code has some pre-defined function classes for this (they are actually quite complex on the math side) and some limited parsing capability but I am not satisfied with this construction at all. What I need is that both the algorithm and the function evaluation remain speedy, so it is advantageous to keep them both as compiled code (and preferrably, the math functions as C++ function objects). However I thought of glueing the whole simulation together with Python: the user could specify the input parameters in a Python script, while also implementing storage, visualization of the results (matplotlib) and GUI, too, in Python. I know that most of the time, exposing C++ classes can be done, e.g. with SWIG but I still have a question concerning the parsing of the user defined math function in Python: Is it possible to somehow to construct a C++ function object in Python and pass it to the C++ algorithm? E.g. when I call f = WrappedCPPGaussianFunctionClass(sigma=0.5) WrappedCPPAlgorithm(f) in Python, it would return a pointer to a C++ object which would then be passed to a C++ routine requiring such a pointer, or something similar... (don't ask me about memory management in this case, though :S) The point is that no callback should be made to Python code in the algorithm. Later I would like to extend this example to also do some simple expression parsing on the Python side, such as sum or product of functions, and return some compound, parse-tree like C++ object but let's stay at the basics for now. Sorry for the long post and thx for the suggestions in advance.

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  • How to extend an existing Ruby on Rails CMS to host multiple sites?

    - by Andrew
    I am trying to build a CMS I can use to host multiple sites. I know I'm going to end up reinventing the wheel a million times with this project, so I'm thinking about extending an existing open source Ruby on Rails CMS to meet my needs. One of those needs is to be able to run multiple sites, while using only one code-base. That way, when there's an update I want to make, I can update it in one place, and the change is reflected on all of the sites. I think that this will be able to scale by running multiple instances of the application. I think that I can use the domain/subdomain to determine which data to display. For example, someone goes to subdomain1.mysite.com and the application looks in the database for the content for subdomain1. The problem I see is with most pre-built CMS solutions, they are only designed to host one site, including the one I want to use. So the database is structured to work with one site. However, I had the idea that I could overcome this by "creating a new database" for each site, then specifying which database to connect to based on the domain/subdomain as I mentioned above. I'm thinking of hosting this on Heroku, so I'm wondering what my options for this might be. I'm not very familiar with Amazon S3, or Amazon SimpleDB, but I feel like there's some sort of "cloud database" that would make this solution a lot more realistic, than creating a new MySQL database for each site. What do you think? Am I thinking about this the wrong way? What advice do you have to offer in this area?

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  • Android AutocompleteView OnClickListener

    - by Chirag_RB
    I have 2 Auto Complete Views which i have to pre-populate with some text .However as soon as user clicks on the views , the text should disappear and allow user to enter text . I have written two separate on click listeners to do so . The On click listener for the first one is working fine . However i have to double click for the On click listener of the second one to work. Please find the chunk of code below and come up with some solution . final AutoCompleteTextView source = (AutoCompleteTextView) findViewById(R.id.source); ArrayAdapter source_adapter = new ArrayAdapter(this, R.layout.list_item, Model.City); source.setAdapter(source_adapter); source.setOnClickListener(new OnClickListener(){ public void onClick(View v) { source.setText(""); source.setTextSize(14); } }); final AutoCompleteTextView destination = (AutoCompleteTextView) findViewById(R.id.destination); ArrayAdapter destination_adapter = new ArrayAdapter(this, R.layout.list_item, Model.City); destination.setAdapter(destination_adapter); destination.setOnClickListener(new OnClickListener(){ public void onClick(View v) { destination.setText(""); destination.setTextSize(14); } });

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  • Handling large datasets with PHP/Drupal

    - by jo
    Hi all, I have a report page that deals with ~700k records from a database table. I can display this on a webpage using paging to break up the results. However, my export to PDF/CSV functions rely on processing the entire data set at once and I'm hitting my 256MB memory limit at around 250k rows. I don't feel comfortable increasing the memory limit and I haven't got the ability to use MySQL's save into outfile to just serve a pre-generated CSV. However, I can't really see a way of serving up large data sets with Drupal using something like: $form = array(); $table_headers = array(); $table_rows = array(); $data = db_query("a query to get the whole dataset"); while ($row = db_fetch_object($data)) { $table_rows[] = $row->some attribute; } $form['report'] = array('#value' => theme('table', $table_headers, $table_rows); return $form; Is there a way of getting around what is essentially appending to a giant array of arrays? At the moment I don't see how I can offer any meaningful report pages with Drupal due to this. Thanks

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  • Is it possible to have a mysql table accept a null value for a primary_key column referencing a diff

    - by Dr.Dredel
    I have a table that has a column which holds the id of a row in another table. However, when table A is being populated, table B may or may not have a row ready for table A. My question is, is it possible to have mysql prevent an invalid value from being entered but be ok with a NULL? or does a foreign key necessitate a valid related value? So... what I'm looking for (in pseudo code) is this: Table "person" id | name Table "people" id | group_name | person_id (foreign key id from table person) insert into person (1, 'joe'); insert into people (1, 'foo', 1)//kosher insert into people (1, 'foo', NULL)//also kosher insert into people(1, 'foo', 7)// should fail since there is no id 7 in the person table. The reason I need this is that I'm having a chicken and egg issue where it makes perfect sense for the rows in the people table to be created before hand (in this example, I'm creating the groups and would like them to pre-exist the people who join them). And I realize that THIS example is silly and I would just put the group id in the person table rather than vice-versa, but in my real-world problem that is not workable. Just curious if I need to allow any and all values in order to make this work, or if there's some way to allow for null.

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  • Converting json data to an HTML table

    - by dnaluz
    I have an array of data in php and I need to display this data in a HTML table. Here is what an example data set looks like. Array( Array ( [comparisonFeatureId] => 1182 [comparisonFeatureType] => Category [comparisonValues] => Array ( [0] => Not Available [1] => Standard [2] => Not Available [3] => Not Available ) [featureDescription] => Rear Seat Heat Ducts ),) The dataset is a comparison of 3 items (shown in the comparisonValues index of the array) In the end I need the row to look similar to this <tr class="alt2 section_1"> <td><strong>$record['featureDescription']</strong></td> <td>$record['comparisonValues'][0]</td> <td>$record['comparisonValues'][1]</td> <td>$record['comparisonValues'][2]</td> <td>$record['comparisonValues'][3]</td> </tr> The problem I am coming across is how to best do this. Should I create the entire table HTML on the server side pass it over an ajax call and just dump pre-rendered HTML data into a div or pass the json data and render the table client side. Any elegant suggestions? Thanks in advanced.

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  • Why changing the images name on server results in calling the old ones?

    - by moderns
    I am running a slideshow on Ubuntu 12.04.1 that loads the images (slide1.jpg, slide2.jpg, slide3.jpg.., slide5.jpg) using the Javascript and styles as below: document.getElementById('slide_area').className='slide'+step; .slide1{background-image: url(../upload/slide1.jpg)} .slide2{background-image: url(../upload/slide2.jpg)} .slide3{background-image: url(../upload/slide3.jpg)} .slide4{background-image: url(../upload/slide4.jpg)} .slide5{background-image: url(../upload/slide5.jpg)} When I change the images names (show1.jpg, show2.jpg, show3.jpg.., show5.jpg) and also change the style as below: .slide1{background-image: url(../upload/show1.jpg)} .slide2{background-image: url(../upload/show2.jpg)} .slide3{background-image: url(../upload/show3.jpg)} .slide4{background-image: url(../upload/show4.jpg)} .slide5{background-image: url(../upload/show5.jpg)} And open the network section on Chrome, I see the server is calling the new name and old name for images! I added the header in the index.php: header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0"); header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past header("Cache-Control: post-check=0, pre-check=0", false); header("Pragma: no-cache"); Nothing worked out with me and the slideshow doesn't work properly when I change the name of images even when clearing the browser cache as I load images sequentially (one by one) depending on imageObject.complete property! But without changing the name everything is going perfect and the images are loaded smoothly! Thank you for your help!

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  • Rate my C# code (~300 SLOC) using GDI+/Backgroundworker

    - by sebastianlarsson
    Hi, I want to get some feedback on my code! Below is some background info. I am taking a pre-certification course in C# (Sweden, 15 ECTS). The focus of the course is theoretical and only limited practical work. I dont find the assignments very hard at all to tell you the truth, but since I only have very limited work experience as a developer (I have worked 15h/week at Ericsson since November) I think I would benefit from having the certificate (70-536 and more probably). I am currently reading Martin Fowler's "Refactoring: Improving the design of existing code" and I tried to apply his techniques to my latest lab in the course. I have been on the lookout for a website which have the idea of providing feedback on code, but so far I have yet to discover any. Please take a look on my code and tell me what you think. It is only roughly 300 lines of code divided into a couple of classes. GDI+, backgroundworker and user controls are what the lab is about. I reckon you may have to spend as little as a couple of minutes on looking on the solution. Link to solution: http://www.filefactory.com/file/b18h7d5/n/Lab4_Lab5_SebastianLarsson.zip Regards and thank you, Sebastian

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