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• Select multiple records by one query

  - by kofto4ka

  Hello there. Please, give me advice, how to construct select query. I have table table with fields type and obj_id. I want to select all records in concordance with next array: $arr = array( 0 => array('type' => 1, 'obj_id' => 5), 1 => array('type' => 3, 'obj_id' => 15), 2 => array('type' => 4, 'obj_id' => 14), 3 => array('type' => 12, 'obj_id' => 17), ); I want to select needed rows by one query, is it real? Smth like select * from `table` where type in (1,3,4,12) and obj_id in (5,15,14,17) But this query returns also records with type = 3 and obj_id = 14, and for example type = 1 and obj_id = 17. p.s. moderators, please fix my title, I dont know how to describe my question.

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• possible to make codeigniter work with another framework?

  - by ajsie

  the situation is this. my client (who also is a programmer) asks me to develop an address book (with mysql database) with a lot of functions. then he can interact with some class methods i provide for him. kinda like an API. the situation is that the address book application is getting bigger and bigger, and i feel like its way better to use CodeIgniter to code it with MVC. i wonder if i can use codeigniter, then in some way give him the access to controller methods. eg. in a controller there are some functions u can call with the web browser. public function create_contact($information) {..} public function delete_contact($id) {..} public function get_contact($id) {..} however, these are just callable from web browser. how can i let my client have access to these functions like an API? then in his own application he can use: $result = $address_book-create_contact($information); if($result) { echo "Success"; } $contact = $address_book-get_contact($id); is this possible? cause i just know how to access the controller methods with the webbrowser. and i guess its not an option for him to use header(location) to access them. all suggestions to make this possible are welcomed! thanks

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• Pass the return type as a parameter in java?

  - by jonderry

  I have some files that contain logs of objects. Each file can store objects of a different type, but a single file is homogeneous -- it only stores objects of a single type. I would like to write a method that returns an array of these objects, and have the array be of a specified type (the type of objects in a file is known and can be passed as a parameter). Roughly, what I want is something like the following: public static <T> T[] parseLog(File log, Class<T> cls) throws Exception { ArrayList<T> objList = new ArrayList<T>(); FileInputStream fis = new FileInputStream(log); ObjectInputStream in = new ObjectInputStream(fis); try { Object obj; while (!((obj = in.readObject()) instanceof EOFObject)) { T tobj = (T) obj; objList.add(tobj); } } finally { in.close(); } return objList.toArray(new T[0]); } The above code doesn't compile (there's an error on the return statement, and a warning on the cast), but it should give you the idea of what I'm trying to do. Any suggestions for the best way to do this?

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• Looking for out-of-place directories in an SVN working copy?

  - by jthg

  An annoyance that I sometimes come across with SVN is the working copy getting corrupted by one of the .svn folders getting moved from its original location. It doesn't happen often if you're careful and use the proper tools for all moves and renames, but it still somehow happens from time to time. First, does anyone know if there's a good way to catch the problem before a commit is even done? Cruise control usually catches the problem, but there are plenty of cases it wouldn't catch. Second, is there a quick and easy way to check for out-of-place .svn folder if I suspect that there is one? I can definitely do it manually by deducing what directory is out of place based on the compiler errors or by diffing the working copy with another clean checkout. But, this seems like a problem that SVN can diagnose in a second by giving me a list of all directories whose parent directory in the working copy doesn't match its parent directory in the repository. There there some way to have SVN give me a list like that? Thanks.

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• Sample twitter App

  - by Jack

  I am now running my code on a web hosting service http://xtreemhost.com/ <?php function updateTwitter($status) { $username = 'xxxxxx'; $password = 'xxxx'; $url = 'http://twitter.com/statuses/update.xml'; $postargs = 'status='.urlencode($status); $responseInfo=array(); $ch = curl_init($url); curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 2); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt ($ch, CURLOPT_POST, true); // Give CURL the arguments in the POST curl_setopt ($ch, CURLOPT_POSTFIELDS, $postargs); // Set the username and password in the CURL call curl_setopt($ch, CURLOPT_USERPWD, $username.':'.$password); // Set some cur flags (not too important) $response = curl_exec($ch); if($response === false) { echo 'Curl error: ' . curl_error($ch); } else { echo 'Operation completed without any errors<br/>'; } // Get information about the response $responseInfo=curl_getinfo($ch); // Close the CURL connection curl_close($ch); // Make sure we received a response from Twitter if(intval($responseInfo['http_code'])==200){ // Display the response from Twitter echo $response; }else{ // Something went wrong echo "Error: " . $responseInfo['http_code']; } curl_close($ch); } updateTwitter("Just finished a sweet tutorial on http://brandontreb.com"); ?> I get the following error now Curl error: Couldn't resolve host 'api.twitter.com' Error: 0 Please somebody solve my problem

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• Deserialization of a DataSet... deal with column name changes? how to migrate data from one column to another?

  - by Brian Kennedy

  So, we wanted to slightly generalize a couple columns in our typed dataset... basically dropped a foreign key constraint and then wanted to change a couple column names to better reflect their new state. All that is easy. The problem is that our users may have serialized out the old version of the DataSet as XML. We want to be able to read those old XML files and deserialize them into the revised DataSet. It seems that would be a fairly common desire... but I haven't yet figured out the right thing to search the internet for. One possible solution would seem to be some way to give a DataColumn an alias or alternate name such that when it reads the old column name, it knows that data can be read into the column with the new column name. I can find no support for any such thing. Another approach would seem to be an "after deserialization" method of some sort... so, I would let it read in the old column values into a normal DataColumn with that name, and then in the "after deserialization" method I would just move the data from the obsolete column into the new column, and then delete the old columns. That would seem to generalize to many other situations... and having such events or hooks is pretty common in ADO.NET. But I have looked for such a hook and haven't yet found it. If no "after deserialization" hook, it would seem I ought to be able to override ReadXml or ReadXmlSerializable methods to call the base and then do my "after" stuff to fix up old data into new. But it does not appear that is possible. Soooo, I have to think backward compatibility with old serialized DataSets and simple data migration would be a well-solved problem... so, trying to reinvent that wheel seems silly. But so far, I haven't seemed to find any documentation on doing those things. Suggestions? What is best practice for this?

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• Facebook call back function with timeout

  - by Dirty Bird Design

  So I've been getting my ass kicked pretty good with Facebook's moving target of an API. I need to display some hidden content after a person clicks 'like' on a landing page. I can somewhat get this to work, when the user clicks 'like' the normal fb dialogue appears and then goes away immediately and content is displayed. I have 'achieved' this with the following js. <script> FB.Event.subscribe('edge.create', function(href, widget) { document.getElementById('goodies').style.display = "block"; document.getElementById('fb-content').style.display= "block"; document.getElementById('copy').style.display = "none"; }); </script> I cannot find any documentation about a callback event after someone hits "post to facebook" or after the dialogue closes, only afte they hit like. How would I incorporate a setTimeout function into this to give people some time to fill out the fb dialogue? thanks. If anyone has a better way to do this I'm all ears. This is for a business page and I cannot seem to add an app to get an app ID anymore so the API is pretty useless to me at this point. Also, if the url to be liked is a fb page, the callbacks don't seem to fire. Other code used: <html xmlns:fb="http://ogp.me/ns/fb#"> <div id="fb-root"></div> <script>(function(d, s, id) { var js, fjs = d.getElementsByTagName(s)[0]; if (d.getElementById(id)) return; js = d.createElement(s); js.id = id; js.src = "//connect.facebook.net/en_US/all.js#xfbml=1"; fjs.parentNode.insertBefore(js, fjs); }(document, 'script', 'facebook-jssdk')); </script> <fb:like href="onlynonfburl.com" send="false" layout="button_count" width="450" show_faces="false" font="arial"></fb:like>

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• when is a v-table created in C++?

  - by saminny

  When exactly does the compiler create a virtual function table? 1) when the class contains at least one virtual function. OR 2) when the immediate base class contains at least one virtual function. OR 3) when any parent class at any level of the hierarchy contains at least one virtual function. A related question to this: Is it possible to give up dynamic dispatch in a C++ hierarchy? e.g. consider the following example. #include <iostream> using namespace std; class A { public: virtual void f(); }; class B: public A { public: void f(); }; class C: public B { public: void f(); }; Which classes will contain a V-Table? Since B does not declare f() as virtual, does class C get dynamic polymorphism?

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• Difference dynami static 2d array c++

  - by snorlaks

  Hello, Im using opensource library called wxFreeChart to draw some XY charts. In example there is code which uses static array as a serie : double data1[][2] = { { 10, 20, }, { 13, 16, }, { 7, 30, }, { 15, 34, }, { 25, 4, }, }; dataset-AddSerie((double *) data1, WXSIZEOF(dynamicArray)); WXSIZEOF ismacro defined like: sizeof(array)/sizeof(array[0]) In this case everything works great but in my program Im using dynamic arrays (according to users input). I made a test and wrotecode like below: double **dynamicArray = NULL; dynamicArray = new double *[5] ; for( int i = 0 ; i < 5 ; i++ ) dynamicArray[i] = new double[2]; dynamicArray [0][0] = 10; dynamicArray [0][1] = 20; dynamicArray [1][0] = 13; dynamicArray [1][1] = 16; dynamicArray [2][0] = 7; dynamicArray [2][1] = 30; dynamicArray [3][0] = 15; dynamicArray [3][1] = 34; dynamicArray [4][0] = 25; dynamicArray [4][1] = 4; dataset-AddSerie((double *) *dynamicArray, WXSIZEOF(dynamicArray)); But it doesnt work correctly. I mean point arent drawn. I wonder if there is any possibility that I can "cheat" that method and give it dynamic array in way it understands it and will read data from correct place thanks for help

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• ( Sql Server 2005 C#.Net ) - I want just the insert query for a temp table.

  - by John Stephen

  Hi..I am using C#.Net and Sql Server ( Windows Application ). I had created a temporary table. When a button is clicked, temporary table (#tmp_emp_details) is created. I am having another button called "insert Values" and also 5 textboxes. The values that are entered in the textbox are used and whenever com.ExecuteNonQuery(); line comes, it throws an error message called "Invalid object name '#tbl_emp_answer'.". Below is the set of code..Please give me a solution. Code for insert (in insert value button): private void btninsertvalues_Click(object sender, EventArgs e) { username = txtusername.Text; examloginid = txtexamloginid.Text; question = txtquestion.Text; answer = txtanswer.Text; useranswer = txtanswer.Text; SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=tempdb;Integrated Security=True;"); SqlCommand com = new SqlCommand("Insert into #tbl_emp_answer values('"+username+"','"+examloginid+"','"+question+"','"+answer+"','"+useranswer+"')", con); con.Open(); com.ExecuteNonQuery(); con.Close(); }

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• What are provenly scalable data persistence solutions for consumer profiles?

  - by Hubbard

  Consumer profiles with analytical scores [ConsumerID, 1..n demographical variables, 1...n analytical scores e.g. "likely to churn" "likely to buy an item 100$ in worth" etc.] have to be possible to query fast if they are to be used in customizing web-sites, consumer communications etc. Well. If you have: Large number of consumers Large profiles with a huge set of variables (as profiles describing human behaviour are likely to be..) ...you are in trouble. If you really have a physical relational database to which you target a query and then a physical disk starts to rotate someplace to give you an individual profile or a set of profiles, the profile user (a web site customizing a page, a recommendation engine making a recommendation..) has died of boredom before getting any observable results. There is the possibility of having the profiles in memory, which would of course increase the performance hugely. What are the most proven solutions for a fast-response, scalable consumer profile storage? Is there a shootout of these someplace?

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• How to override jquery's show() and hide() functions

  - by Max Williams

  hi all Short version of question: see title Long version of question: I've used jquery's show() and hide() functions extensively in my code and just encountered a bit of a problem: they work by changing the display attribute of the element to 'block' or 'none' respectively, so that if you have somethin that has display: inline and then hide and show it, you've changed its display to block, which screws up the layout in a couple of cases. In my code, whenever i want something to be hidden initially i give it a class 'hidden'. This class is simply {display: none}. I'd like the change show and hide to remove or add this class, instead of directly changing the display attribute, so that if you add the hidden class and then remove it again (ie hide and show something) then it's back to exactly how it was to start off with (since adding a class overrides the attributes rather than directly changing them). Something like this (this is a little pseucodey as i don't know how to set the function up properly - let's assume that 'this' is the object that show/hide was called on) function show(){ this.removeClass("hidden"); } function hide(){ this.addClass("hidden"); } how and where would i go about overriding the jquery methods? (I'm not a javascript expert) thanks - max

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• [^.] causing headache in RewriteRule

  - by Ollie2893

  I am struggling with a very basic regex problem in my .htaccess file that I hope someone may be able to shed some light on. The basic premise is that I would like to teach Apache to switch any .html extension into a .var extension. I had thought that the rule would be positively trivial: RewriteRule ^([^.]+)\.html$ $1.var But the [^.] part simply doesn't work. Bizarrely, it works like so RewriteRule ^([^A-Z]+)\.html$ $1.var I do not understand why this latter rule works. Assume I am looking for a file called "index.html" then $1 should match to "index." and the ".html" bit should actually fail to match. To widen the scope of the question slightly, I am actually racking my brain on how to implement a multi-lingual site. I don't like Apache's MultiView option because it forces upon me a flat directory structure with file extensions that aren't recognizable to many development tools. I could go the .var type-map route but am finding that the default config for Apache doesn't support this all that well either (hence my excursions into regex land). So while I am using mod_rewrite, I am thinking that I might go the whole hog: whenever a request for a name.html file is received and this file does not exist, check whether there exists a XX/name.html file instead, where "XX" is the language code according to the user's preferences. This would give me a neater directory structure, though it does perhaps not perform as well as the .var approach in a situation where the language preference of the user's browser is not supported in by my site (in which situation .var would substitute EN or similar). Any thoughts? Thanks.

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• please help me to solve problem

  - by davit-datuashvili

  first of all this is not homework and nobody tag it as homewrok i did not understand this porblem can anybody explain me?this is not english problem it is just misunderstanding what problem say Consider the problem of neatly printing a paragraph on a printer. The input text is a sequence of n words of lengths l1 , l2 , . . . , ln , measured in characters. We want to print this paragraph neatly on a number of lines that hold a maximum of M characters each. Our criterion of “neatness” is as follows. If a given line contains words i through j , where i = j , and we leave exactly one space between words, the number of extra space characters at the end of the line is M - j + i -(k=i,k< j,k++) lk , which must be nonnegative so that the words fit on the line. We wish to minimize the sum, over all lines except the last, of the cubes of the numbers of extra space characters at the ends of lines. Give a dynamic-programming algorithm to print a paragraph of n words neatly on a printer. Analyze the running time and space requirements of your algorithm.

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• Prolog Beginner: How to unify with arithmentic cmparison operators or how to get a set var to range

  - by sixtyfootersdude

  I am new to prolog. I need to write an integer adder that will add numbers between 0-9 to other numbers 0-9 and produce a solution 0-18. This is what I want to do: add(in1, in2, out) :- in1 < 10, in2 < 10, out < 18. I would like to be able to call it like this: To Check if it is a valid addition: ?- add(1,2,3). true ?- add(1,2,4). false With one missing variable: ?- add(X,2,3). 1 ?- add(1,4,X). 5 With multiple missing variables: ?-add(X,Y,Z). % Some output that would make sense. Some examples could be: X=1, Y=1, Z=2 ; X=2, Y=1, Z=3 ...... I realize that this is probably a pretty simplistic question and it is probably very straightforward. However cording to the prolog tutorial I am using: "Unlike unification Arithmetic Comparison Operators operators cannot be used to give values to a variable. The can only be evaluated when every term on each side have been instantiated."

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• Extracting exported functions out of a shared lib (ubuntu)

  - by Pingu

  the title already describes my problem. I found this post, but it didn't completely answers my question. With the help of it i got this output from nm... $nm -C -g -D ./libLoggingHandler.so 000000cc A _DYNAMIC ... 000042e0 T write_str(char*, char const*, int*) 00005a78 T RingBuffer::WriteUnlock() ... 00005918 T TraceLines::GetItemSize() ... U SharedMemory::attach(int, void const*, int) ... 00003810 T TraceProfile::FindLineNr(int, int) ... 00002d40 T LoggingHandler::getLogLevel() ... U SharedResource::getSharedResourceKey(char const*, int) ... which are the exported functions? I already found a hint in this post, that the "T" indicates that its getting exported. But if i check the nm manual here, it just says T - The symbol is in the text (code) section. My questions is: Does this output give me the information which functions are exported functions (or variables)? If not, how do i get it? Greetings, Pingu

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• cURL/PHP Request Executes 50% of the Time

  - by makavelli

  After searching all over, I can't understand why cURL requests issued to a remote SSL-enabled host are successful only 50% or so of the time in my case. Here's the situation: I have a sequence of cURL requests, all of them issued to a HTTPS remote host, within a single PHP script that I run using the PHP CLI. Occasionally when I run the script the requests execute successfully, but for some reason most of the times I run it I get the following error from cURL: * About to connect() to www.virginia.edu port 443 (#0) * Trying 128.143.22.36... * connected * Connected to www.virginia.edu (128.143.22.36) port 443 (#0) * successfully set certificate verify locations: * CAfile: none CApath: /etc/ssl/certs * error:140943FC:SSL routines:SSL3_READ_BYTES:sslv3 alert bad record mac * Closing connection #0 If I try again a few times I get the same result, but then after a few tries the requests will go through successfully. Running the script after that again results in an error, and the pattern continues. Researching the error 'alert bad record mac' didn't give me anything helpful, and I hesitate to blame it on an SSL issue since the script still runs occasionally. I'm on Ubuntu Server 10.04, with php5 and php5-curl installed, as well as the latest version of openssl. In terms of cURL specific options, CURLOPT_SSL_VERIFYPEER is set to false, and both CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT are set to 4 seconds. Further illustrating this problem is the fact that the same exact situation occurs on my Mac OS X dev machine - the requests only go through ~50% of the time.

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• Do I need a spatial index in my database?

  - by Sanoj

  I am designing an application that needs to save geometric shapes in a database. I haven't choosen the database management system yet. In my application, all database queries will have an bounding box as input, and as output I want all shapes within that database. I know that databases with a spatial index is used for this kind of application. But in my application there will not be any queries of type "give me objects nearby x/y" or other more complex queries that are useful in a GIS application. I am planning of having a database without a spatial index and have queries looking like: SELECT * FROM shapes WHERE x < max_x AND x > min_x AND y < max_y AND y > min_y And have an index on the columns x (double) and y (double). As long I can see, I don't really need a database with an spatial index, howsoever my application is close to that kind of applications. And even if I would like to have nearby queries, then I could create a big enough bounding box around that point. Or will this lead to poor performance? Do I really need a spatial database? And when is a spatial index needed?

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• Using multiple Qt (SQL) Models

  - by radix07

  I have a near real-time application that I am using Qt and an SQLite database to run. I am curious if it is safe to have two separate models access a database at once. I know 2 separate views can access a model just fine, but I can't find any document addressing this. I also realize that SQLite is thread safe for reading, so I don't see a real issue to doing this from the SQLite part of things... Basically I want to use a QSqlTableModel to do the real-time read and write in the background and at the same time use a QSqlQueryModel to give the user desired data. Since I may be doing lots of filtering in the background using the table model I can't use it as the main view as well. I have gotten this to work for the most part, but am not sure if this is the best way to do this. If the models act like multiple SQL queries I don't believe this should be an issue, but I would like to know from someone I bit more knowledgeable about this stuff since this is pretty new to me. Thanks

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• Lookback API: How long is a defect in a particular state?

  - by user1195996

  We have a state in our defects called "Need More Information". I would like to create a graph over time of how many defects are in that state at any particular period of time. I think I can get the info to do that with the Lookback API with the following query: my $find = { State => 'Need More Information', '_PreviousValues.State' => {'$ne' => 'Need More Information'}, _TypeHierarchy => -51006, # defect _ValidFrom => { '$gte' => '2012-09-01TZ', '$lt' => '2012-10-23TZ', } I thought that would give me back a list of all defect snapshots where the defect was transitioning into "Need More Information" state, but it does not (seems to list everything that was ever in "Need More Information" state. Technically what I need is a query that lists snapshots of any defects transitioning either TO OR FROM the "Need More Information" state, but since this simpler one did not seem to work as I expected, I thought I would ask first why the query above did not work the way I expected.

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• How to start x-axis labels(dates) from 0th position without using set_range(..)

  - by Rishi2686

  Hi there, First of all, I am really a newbie for flash charts. I have problem in using it. I am developing an app which gets values from database for chart. I have a line on chart, there are dates on x-axis starting from 0th position. I have dates 03-06-2010 and 05-06-2010 right now and may increase in future. When I set range of 1 month i.e 1st jun to 30th jun , it does not show lines but show values on y-axis. When I use range, i am not able to pass array of above two dates from database to chart, and viceversa. Here is my code-snippet can you give some hint. $x = new x_axis(); $x->set_range( mktime(0, 0, 0, 6, 1, date('Y')), // <-- min == 1st Jan, this year mktime(0, 0, 0, 6, 16, date('Y')) // <-- max == 31st Jan, this year ); $x->set_steps(86400); $labels = new x_axis_labels(); $labels->text('#date: jS, M Y#'); $labels->set_steps(86400); $labels->visible_steps(1); $labels->rotate(90); //$labels->set_labels($data_4); // date_4 is array of database values $x->set_labels($labels);

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• Flash Player, security: If a URL starts with "http://" will the SWF always be loaded into REMOTE san

  - by Pavel

  Seems to be a question for a Flash security guru. Suppose we are loading an external SWF movie with MovieClipLoader.loadMovie(url:String) Is it safe to assume that if url starts with "http://", the movie will be loaded in REMOTE sandbox? We need to tell local SWFs from remote ones to close a security hole. If you need the context read on. We have developed a Projector, written in C++ embedding Flash Player ActiveX. Our Flash application runs inside the Projector. Soon we want to give our users a way to create plugins for the application. The plugins are obviously will be SWF movies. The case I'm afraid of is the following. A bad person creates a malicious evil.swf pretending it to be nice plugin for our app. In case evil.swf is loaded from the local file system it is granted an access to the whole MovieClip tree and Projector API, opening C++ file access operations. On the other hand if evil.swf is loaded from the internet, remotely, it will be locked in REMOTE sandbox by Flash security model. Because of this, we need a reliable way to tell local SWF from remote one before loading it. And we must not make a mistake. So again, is it safe to assume that if url begins with "http://", the clip will be loaded inside REMOTE sandbox?

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• Change clickable TextView's color on focus and click?

  - by Daniel Jonsson

  I have a clickable TextView that I want to give some colors to. But I don't know how. Here are the relevant code snippets from my two files that I'm working with: TextView title = new TextView(this); title.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT)); title.setTextColor(R.color.textcolor); title.setText(titleLine); title.setTypeface(null, Typeface.BOLD); title.setClickable(true); title.setId(idLine); title.setFocusable(true); title.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { /* Irrelevant code */ } }); And this is my textcolor.xml file: <?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_pressed="true" android:color="#000000"/> <!-- pressed --> <item android:state_focused="true" android:color="#000000"/> <!-- focused --> <item android:color="#000000"/> <!-- default --> </selector> When I use the textcolor-file by typing title.setTextColor(R.color.textcolor);, the textcolor just becomes grey, regardless if I press it or so. Which is strange since I have written "#000000" in all color fields. But if I remove the setTextColor code, gets the textView a light grey color, and when I press it, it becomes black. But that aren't the colors that I want. So, can anyone help me with this problem? Just to clarify: I want to be able to specify the colors for the text when it's normal, pressed and focused.

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• Generics in a bidirectional association

  - by Verhoevenv

  Let's say I have two classes A and B, with B a subtype of A. This is only part of a richer type hierarchy, obviously, but I don't think that's relevant. Assume A is the root of the hierarchy. There is a collection class C that keeps track of a list of A's. However, I want to make C generic, so that it is possible to make an instance that only keeps B's and won't accept A's. class A(val c: C[A]) { c.addEntry(this) } class B(c: C[A]) extends A(c) class C[T <: A]{ val entries = new ArrayBuffer[T]() def addEntry(e: T) { entries += e } } object Generic { def main(args : Array[String]) { val c = new C[B]() new B(c) } } The code above obviously give the error 'type mismatch: found C[B], required C[A]' on the new B(c) line. I'm not sure how this can be fixed. It's not possible to make C covariant in T (like C[+T <: A]) because the ArrayBuffer is non-variantly typed in T. It's not possible to make the constructor of B require a C[B] because C can't be covariant. Am I barking up the wrong tree here? I'm a complete Scala newbie, so any ideas and tips might be helpful. Thank you! EDIT: Basically, what I'd like to have is that the compiler accepts both val c = new C[B]() new B(c) and val c = new C[A]() new B(c) but would reject val c = new C[B]() new A(c) It's probably possible to relax the typing of the ArrayBuffer in C to be A instead of T, and thus in the addEntry method as well, if that helps.

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• Which one gives you more advantages: Microsoft or SUN/Oracle certification?

  - by edwin.nathaniel

  Which one gives you more advantages: Microsoft or SUN/Oracle certification? If you don't mind, please relate your answer to your career (dev, sys-admin, dba), industry (finance, general consulting, business apps, software house), and location (where you live, does it influence your decision?) as well. One reason I asked this because I heard that having MCP (in C#, MCSAD or whatever the cert is called these days) could give you extra point from the employer perspective if they're a Microsoft Partner. I don't quite understand why and am also wondering if SUN/Oracle certificate holder have similar edge/benefit. I'm also interested to know if Certification plays role where you live. For example: certification could be a big negative sign in Silicon Valley, but might be helpful if you're in other US/Canada cities or outside USA/Canada. If you are an independent software consultant, do these certification helps you win bids? I totally understand that this question might be subjective and could be "closed". But it doesn't hurt to ask I suppose. I also understand that there are people who dislike/disagree (or have negative perspective on technology certification). While there are people who have the opinion that "these are not the kind of employers you would want to work with", I respect you guys, but sometime a pure software product company might not exist in certain cities in the world. And if certification can help one's career somewhere else, I guess that means more opportunities right? I've had experienced in both platforms: (short) .NET and (not too long) Java (minus Oracle DB stuff), but I think it's about time I have to pick one of them and be good at. Where I live right now might also dictates my career albeit insignificant. Anyhow, this last paragraph is just tiny blurb. Thanks!

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