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  • Run Jmol applet using apache server

    - by user1144004
    I am a newbie in using apache and jmol. I am trying to run a jmol applet in python using apache server. Because of strict folder arrangement restrictions in jmol (html and model files should be present inside jmol folder), I had to move the default htdocs and cgi-bin folder inside jmol folder by editing the "httd.conf" file. Now the new location of htdocs folder is "Apache2.2/jmol/htdocs" and of cgi-bin folder is "Apache2.2/jmol/cgi-bin". Now I've put my "start.html" file in the htdocs folder which has the jmol applet tag. It takes "CA150.XYZ" file which is also placed in the same folder. On running this "start.html" file through apache server, nothing happens. It even doesn't give any error, it just shows a blank page. But if I try to run "start.html" without apache server, jmol applet do get executed and runs successfully. What am I doing wrong? Any idea? Here is my "start.html" file <head> <title>Simple example</title> <script src="../Jmol.js" type="text/javascript"></script> </head> <body> <form> <script type="text/javascript"> jmolInitialize("../"); jmolApplet(200,"load CA150.XYZ"); </script> </form> </body>

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  • HELP A NEWB (AGAIN) PLZ

    - by Ken
    Okay, I must be an idiot, because this is my 3rd question for today. Here's my code: date_default_timezone_set("America/Los_Angeles"); include("mainmenu.php"); $con = mysql_connect("localhost", "root", "********"); if(!$con){ die(mysql_error()); } $usrname = $_POST['usrname']; $fname = $_POST['fname']; $lname = $_POST['lname']; $password = $_POST['password']; $email = $_POST['email']; mysql_select_db("`users`, $con) or die(mysql_error()"); $query = ("INSERT INTO `users`.`data` (`id`, `usrname`, `fname`, `lname`, `email`, `password`) VALUES (NULL, '$usrname', '$fname', '$lname', '$email', 'password'))"); mysql_query('$query') or die(mysql_error()); mysql_close($con); echo("Thank you for registering!"); I always get the error returned as: "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '$query' at line 1. Help a newbie. I'm about to stab my monitor.

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  • Python programming - Windows focus and program process

    - by Zack
    I'm working on a python program that will automatically combine sets of files based on their names. Being a newbie, I wasn't quite sure how to go about it, so I decided to just brute force it with the win32api. So I'm attempting to do everything with virtual keys. So I run the script, it selects the top file (after arranging the by name), then sends a right click command,selects 'combine as adobe PDF', and then have it push enter. This launched the Acrobat combine window, where I send another 'enter' command. The here's where I hit the problem. The folder where I'm converting these things loses focus and I'm unsure how to get it back. Sending alt+tab commands seems somewhat unreliable. It sometimes switches to the wrong thing. A much bigger issue for me.. Different combination of files take different times to combine. though I haven't gotten this far in my code, my plan was to set some arbitrarily long time.sleep() command before it finally sent the last "enter" command to finish and confirm the file name completing the combination process. Is there a way to monitor another programs progress? Is there a way to have python not execute anymore code until something else has finished?

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  • XCode Obj-C: Make new NSArray from one key each out of an Array of Dictionaries

    - by user323772
    This actually could be a multipart question. But here's the first part ... I have an array (actually in a plist) of dictionaries. Each dictionary has 3 keys in it: (title), (points), and (description). I am trying to make a NEW array with the values of the key "title" from each dictionary in that first array. Let me explain WHY I am doing this and maybe that will provide a better all around explanation. I am trying to let people pick from a pre-determined list. Heck, if this was a web page it would be very simple since all I really care about are the "points" and the "Title". On a web site I could simply do a drop down combo-box with the "points" being the value and the title being the text for each row. But this is not a web page. So what I am trying to do here is pop out a modal picker when they click the text field. The modal picker shows the alphabetical ordered "titles" from our new array. And whichever one they select, it closes the modal view and assigns that "title" text to the UITextField which cannot be edited by the user. I have some code to get my modal picker to pop out. But I need to feed it an array of just the "titles" of each dictionary in my real array. Thanks in advance (and yes I am a newbie)

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  • Writing data into New NFC Tag not works?

    - by Nagaraj436
    I am Newbie to NFC Android App Development. I am done with the App development and everything worked fine. As part of my testing I used MifareClassic as well MifareDesfire tags to write and read. I am storing data in Ndef format. Initially I used the above testing tags with other apps like Nxp tagwriter and Tagstand Tagwriter and then I used with My app. So everything worked fine. Even later I used my app to write and read data from Sony Felica tags(new tags) which also worked fine. So I passed app to client for review but I came to know that app is not writing on New Tags. If they are reset from other apps then It works fine. So I done the same test here and found the same issue as client reported. What might be the issue? Has someone come across same kind of issue? Is it required to format before using? if so how to do that? Someone Help to solve the issue. Thanks in Advance.

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  • LINQ to SQL - database relationships won't update after submit

    - by Quantic Programming
    I have a Database with the tables Users and Uploads. The important columns are: Users -> UserID Uploads -> UploadID, UserID The primary key in the relationship is Users -> UserID and the foreign key is Uploads -> UserID. In LINQ to SQL, I do the following operations: Retrieve files var upload = new Upload(); upload.UserID = user.UserID; upload.UploadID = XXX; db.Uploads.InsertOnSubmit(upload) db.SubmitChanges(); If I do that and rerun the application (and the db object is re-built, of course) - if do something like this: foreach(var upload in user.Uploads) I get all the uploads with that user's ID. (like added in the previous example) The problem is, that my application, after adding an upload an submitting changes, doesn't update the user.Uploads collection. i.e - I don't get the newly added uploads. The user object is stored in the Session object. At first, I though that the LINQ to SQL Framework doesn't update the reference of the object, therefore I should simply "reset" the user object from a new SQL request. I mean this: Session["user"] = db.Users.Where(u => u.UserID == user.UserID).SingleOrDefault(); (Where user is the previous user) But it didn't help. Please note: After rerunning the application, user.Uploads does have the new upload! Did anyone experience this type of problem, or is it normal behavior? I am a newbie to this framework. I would gladly take any advice. Thank you!

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  • How do I select column(s) by their "numeric" position in a table?

    - by DulcimerDude
    I am trying to select columns by their "x" position in the table. DBI my $example = $hookup->prepare(qq{SELECT This,That,Condition,"I also want COLUMN-10" FROM tbl LIMIT ? ?}); ###column_number=10 ordinal_position?? $example->execute('2','10') or die "Did not execute"; Is this possible or do I need to run another single select to just that column? One problem I encountered was with a col named "Condition". For some reason, when I tried to select Condition the execute would die. I never attempted but, What if the column name was SELECT? Another note is the table is 75 cols wide and I only need 50 of them. The Col names are pretty verbose so, I would like to just call them by their "position". This would also allow the col names to be changed in the future without having to change the select statement. I am quite the newbie so please explain any answers down to my level. Thanks for any assistance..

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  • IntelliJ inspection -- non-thrown exception

    - by skiaddict1
    This is a follow-up question to 1832203. I'm making it a new question as well, because it seems that posting an answer to a question doesn't change its position on the java page and so I'm worried that it won't get seen. Apologies if I've just stepped on some etiquette toes. I'm an IntelliJ newbie -- started using it two days ago and I'm absolutely head-over-heels in love! One of the things I adore is the code inspections. However... In one of my classes I often create exceptions without throwing them. If I can't turn off (or downgrade) the inspection warning for this then I can see I'm going to end up ignoring inspections on at least that file (if not the entire project), which would be a real pity. I've done a search in the inspection settings for "exception", and found nothing that relates exactly, so I turned them all off just to see, and it's still doing it (even after a rebuild...BTW when are inspections redone? at save? at rebuild? ???), so I would really like some help on how to make this one into an info/typo level -- which I can then ignore. Using the free version, if that makes any difference TIA to all those experienced IntelliJ warriors out there!

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  • C#: Passing data to forms UI using BeginInvoke

    - by Bi
    Hi I am a C# newbie and have a class that needs to pass row information to a grid in the windows form. What is the best way to do it? I have put in some example code for better understanding. Thanks. public class GUIController { private My_Main myWindow; public GUIController( My_Main window ) { myWindow = window; } public void UpdateProducts( List<myProduct> newList ) { object[] row = new object[3]; foreach (myProduct product in newList) { row[0] = product.Name; row[1] = product.Status; row[2] = product.Day; //HOW DO I USE BeginInvoke HERE? } } } And the form class below: public class My_Main : Form { //HOW DO I GO ABOUT USING THIS DELEGATE? public delegate void ProductDelegate( string[] row ); public static My_Main theWindow = null; static void Main( ) { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); theWindow = new My_Main(); Application.Run(theWindow); } private void My_Main_Load( object sender, EventArgs e ) { /// Create GUIController and pass the window object gui = new GUIController( this ); } public void PopulateGrid( string[] row ) { ProductsGrid.Rows.Add(row); ProductsGrid.Update(); } } Thanks!

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  • Visutal Studio Warning "Content is not allowed" in ASP.NET project

    - by pstar
    Hi, I am just started working as a programmer last month, so there will be plenty of newbie question come from me, stay tuned... I am now working on modify the provided template (from DevExpress) to create new web form using ASP.NET 2.0 on Visual Studio 2008. While the functionality of that web form is there, I am in the process of get rid of ninety something warning message, most of them come from the provided template. One of them puzzled me for a while is this one: "Warning 75 Content is not allowed between the opening and closing tags for element 'ClientSideEvents'." And here is the code: <dxe:ASPxListBox id="edtMultiResource" runat="server" width="100%" SelectionMode="CheckColumn" DataSource='<%# ResourceDataSource %>' Border-BorderWidth="0"> <ClientSideEvents SelectedIndexChanged="function(s, e) { var resourceNames = new Array(); var items = s.GetSelectedItems(); var count = items.length; if (count > 0) { for(var i=0; i<count; i++) _aspxArrayPush(resourceNames, items[i].text); } else _aspxArrayPush(resourceNames, ddResource.cp_Caption_ResourceNone); ddResource.SetValue(resourceNames.join(', ')); }"></ClientSideEvents> </dxe:ASPxListBox> I couldn't see anything wrong with the code myself, so please help me out here.

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  • Manage more Images to move in View

    - by David Pollak
    hi everyone, I'm creating an app which has more UIImageView on a View, they should move normally from a side to the other. I have an issue: after entering the second image, the two UIImageView start to behave crazy (!) because they don' move freely, but they are like restricted in two different areas not touching each other even if I said different things the first thing that I want to do, is to let them move normally; this is the code I am using: `- (void)viewDidLoad { [super viewDidLoad]; pos = CGPointMake(14.0, 7.0); [NSTimer scheduledTimerWithTimeInterval:0.05 target:self selector:@selector(onTimer) userInfo:nil repeats:YES]; }` - (void) onTimer { pallone.center = CGPointMake(pallone.center.x+pos.x, pallone.center.y+pos.y); if(pallone.center.x > 320 || pallone.center.x < 0) pos.x = -pos.x; if(pallone.center.y > 480 || pallone.center.y < 0) pos.y = -pos.y; } and for the other image that has to enter after: - (IBAction)spara{ cos = CGPointMake(8.0, 4.0); [NSTimer scheduledTimerWithTimeInterval:0.05 target:self selector:@selector(inTimer) userInfo:nil repeats:YES]; } - (void)inTimer{ bomba.center = CGPointMake(bomba.center.x+pos.x, bomba.center.y+pos.y); if(bomba.center.x > 50 || bomba.center.x < 0) pos.x = -pos.x; if(bomba.center.y > 480 || bomba.center.y < 0) pos.y = -pos.y; } what should I change ? and if I'd like the images to move only in one way (y) ? how do I do this ? I know, I'm a newbie thanks in advance

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  • How do you program a custom WordPress plug-in?

    - by James
    I have seen several WordPress plug-ins for adding a "quote of the day" feature (or something similar) to your blog. How do you create a customized one? I'm looking for something that will pull a daily entry from a list/database of my creation. I apologize if my question is not detailed enough. Still a newbie with WordPress. PART 2: Thanks for your prompt and on-point responses. With your responses and some additional research, I'm able to fine-tune my question. What I wish to accomplish is something similar to Amazon's Deal of the Day widget. Except, in my case, it will simply be a title and a corresponding link. My presumption is that I will set up a database and (using php or something similar) have the information drawn from the database and displayed in my WP sidebar. Additionally, I forgot to mention the time element. I want the displayed info to update once a day, at or around the same time each day. Any ideas? Thanks again. I'm so glad I found stackoverflow.

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  • In Python, how to make data members visible to subclasses if not known when initializing an object ?

    - by LB
    The title is a bit long, but it should be pretty straightforward for someone well-aware of python. I'm a python newbie. So, maybe i'm doing things in the wrong way. Suppose I have a class TreeNode class TreeNode(Node): def __init__(self, name, id): Node.__init__(self, name, id) self.children = [] and a subclass with a weight: class WeightedNode(TreeNode): def __init__(self,name, id): TreeNode.__init__(self, name, id) self.weight = 0 So far, i think I'm ok. Now, I want to add an object variable called father in TreeNode so that WeightedNode has also this member. The problem is that I don't know when initializing the object who is going to be the father. I set the father afterwards with this method in TreeNode : def set_father(self, father_node): self.father = father_node The problem is then when i'm trying to access self.father in Weighted: print 'Name %s Father %s '%(self.name, self.father.name) I obtain: AttributeError: WeightedNode instance has no attribute 'father' I thought that I could make father visible by doing something in TreeNode.__init__ but i wasn't able to find what. How can i do that ? Thanks.

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  • How to format JSON Date?

    - by Mark Struzinski
    I'm taking my first crack at AJAX with jQuery. I'm getting my data onto my page, but I'm having some trouble with the JSON that is returned for Date data types. Basically, I'm getting a string back that looks like this: /Date(1224043200000)/ From a total newbie at JSON - How do I format this to a short date format? Should this be handled somewhere in the jQuery code? I've tried the jQuery.UI.datepicker plugin using $.datepicker.formatDate() wiuth no success. FYI: Here's the solution I came up with using a combination of the answers here: function getMismatch(id) { $.getJSON("Main.aspx?Callback=GetMismatch", { MismatchId: id }, function(result) { $("#AuthMerchId").text(result.AuthorizationMerchantId); $("#SttlMerchId").text(result.SettlementMerchantId); $("#CreateDate").text(formatJSONDate(Date(result.AppendDts))); $("#ExpireDate").text(formatJSONDate(Date(result.ExpiresDts))); $("#LastUpdate").text(formatJSONDate(Date(result.LastUpdateDts))); $("#LastUpdatedBy").text(result.LastUpdateNt); $("#ProcessIn").text(result.ProcessIn); } ); return false; } function formatJSONDate(jsonDate){ var newDate = dateFormat(jsonDate, "mm/dd/yyyy"); return newDate; } This solution got my object from the callback method and displayed the dates on the page properly using the date format library.

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  • Tkinter, Python: How do I save text entered in the Entry widget? How do I move a label?

    - by user3692825
    I am a newbie at programming and my program is not stellar but hopefully it's ok because I have only been using it for a couple days now. I am having trouble in my class "Recipie". In this class I am having trouble saving the text in my Entry widget. I know to use the .get() option but when I try to print it, it doesn't (whether it is within that defined method or not). So that is my main concern. I want it to save the text entered as a string when I press the button: b. My other minor question is, how can I move the label. When I have tried I have used the height and width options, but that just expands the label. I want to move the text to create a title above my Entry boxes. Is label the right widget to use or would it be easier to use a message box widget? So it would look like, for example (but like 8 pixels down and 20 to the right): ingredients textbox button labeled as: add an ingredient And I am not sure the option .pack(side="...") or .place(anchor="...") are the right options to use for my buttons or entry boxes or labels. Any help is greatly appreciated!!! And if you could add comments to your code explaining what you did, that would be so helpful. Thank you!!! import Tkinter class Recipie(Tkinter.Tk): def __init__(self): Tkinter.Tk.__init__(self) self.title("New Recipie") self.geometry("500x500") def name(self): name = Tkinter.Label(self, text="Title:", width=39) name.place(anchor="nw") insert_name = Tkinter.Entry(self) insert_name.pack() insert_name.focus_set() def ingredients(self): e = Tkinter.Entry(self) e.pack() e.focus_set() def addingredient(self): but = Tkinter.Button(self, text="Add Ingredients", width=15, command=self.ingredients) but.pack(side="bottom") def procedure(self): txt = Tkinter.Label(self, text="List the Steps:") txt.place(anchor="n") p = Tkinter.Entry(self) p.place(anchor="nw") p.focus_set() def savebutton(self): print insert_name.get() print e.get() print p.get() b = Tkinter.Button(self, text="Save Recipie", width=15, command=savebutton) top = Recipie() top.mainloop()

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  • cakephp - form for belongsTo Model

    - by user1511579
    I createt the following model to link 2 relational tables: class Ficha extends AppModel { //public $useTable = 'ficha_seg'; var $primaryKey = 'id_ficha'; var $name = 'Ficha'; var $belongsTo = array( 'Perigo' => array( 'className' => 'Perigo', 'foreignKey' => false, 'conditions' => 'Perigo.id_fichas = Ficha.id_ficha' ) ); } Now, i have a form that requires data from the class Ficha, and then is redirected to another ctp page where i will input the data for the table "Perigos". However, since i'm still a newbie in cakephp i'm having difficult building that second form to insert the data on the table "Perigos". Here goes the code i built at the moment related to the second form: FichasController.php (the method where is it supposed to save the data on the table "Perigos": public function preencher_ficha(){ if ($this->request->is('ficha')) { $this->Ficha->create(); if ($this->Ficha->Perigo->save($this->request->data)) { $last_id=$this->Ficha->getLastInsertID(); $this->Session->setFlash('Your post has been updated '.$last_id.'.'); //$this->redirect(array('action' => 'preencher_ficha')); } else { $this->Session->setFlash('Unable to qualquer coisa your post.'); } } } The preencher_ficha.ctp file with the form: echo $this->Form->create('Ficha->Perigo', array('action' => 'index')); echo $this->Form->input('class_subst', array('label' => 'Classificação:')); echo $this->Form->input('simbolos_perigo', array('label' => 'Símbolos:')); echo $this->Form->input('frases_r', array('label' => 'Frases:')); echo $this->Form->end('Finalizar Ficha'); Here i guess the create part is wrong, but i think i have errors too in the controller part.

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  • Java if/else behaving strangely

    - by Alex
    I'm a real newbie to java, so please excuse me if this is a hopelessly straightforward problem. I have the following from my java game server: // Get input from the client DataInputStream in = new DataInputStream (server.getInputStream()); PrintStream out = new PrintStream(server.getOutputStream()); disconnect=false; while((line = in.readLine().trim()) != null && !line.equals(".") && !line.equals("") && !disconnect) { System.out.println("Received "+line); if(line.equals("h")){ out.println("h"+EOF); // Client handshake System.out.println("Matched 1"); }else if (line.equals("<policy-file-request/>")) { out.println("..."+EOF); // Policy file System.out.println(server.getInetAddress()+": Policy Request"); disconnect=true; System.out.println("Matched 2"); }else if(line.substring(0,3).equals("GET")||line.substring(0,4).equals("POST")){ out.println("HTTP/1.0 200 OK\nServer: VirtuaRoom v0.9\nContent-Type: text/html\n\n..."); // HTML status page disconnect=true; System.out.println("Matched 3"); } else { System.out.println(server.getInetAddress()+": Unknown command, client disconnected."); disconnect=true; System.out.println("Matched else"); } } server.close(); First of all, the client sends an "h" packet, and expects the same back (handshake). However, I want it to disconnect the client when an unrecognised packet is received. For some reason, it responds fine to the handshake and HTML status request, but the else clause is never executed when there's an unknown packet. Thanks

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  • Determining Best Table Structure for MySQL Performance

    - by Joe Majewski
    I'm working on a browser-based RPG for one of my websites, and right now I'm trying to determine the best way to organize my SQL tables for performance and maintenance. Here's my question: Does the number of columns in an SQL table affect the speed in which it can be queried? I am not a newbie when it comes to PHP or MySQL. I used to develop things with the common goal of getting them to work, but I've recently advanced to the stage where a functional program is not good enough unless it's fast and reliable. Anyways, right now I have a members table that has around 15 columns. It contains information such as the player's username, password, email, logins, page views, etcetera. It doesn't contain any information on the player's progress in the game, however. If I added columns for things such as army size, gold, turns, and whatnot, then it could easily rise to around 40 or 50 total columns. Oh, and my database structure IS normalized. Will a table with 50 columns that gets constantly queried be a bad idea? Should I split it into two tables; one for the user's general information and one for the user's game statistics? I know I could check the query time myself, but I haven't actually created the tables yet and I think I'd be better off with some professional advice on this important decision for my game. Thank you for your time! :)

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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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  • Trouble managing events in Flex/actionscript

    - by Zaka
    Hello all, I'm doing some newbie tests, so I decided to capture the keyboard events to move a rectangle. But I don't get the desired result. Unless I click on the TextArea box, I'm not able to capture the event key code. After that, all goes pretty well. I'm using Eclipse 3.3 + Flex 3.0 on Linux. Here's my code: <?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" enterFrame="enterFrame(event)" keyDown="onKeyDown(event)"> <mx:TextArea id="myText" x="200" y="200" width="100" height="100" /> <mx:Canvas id="myCanvas" x="0" y="0" width="100" height="100" /> <mx:Script> <![CDATA[ public var clearColor : uint = 0xFF456798; public var myPoint : Point = new Point(0,0); public function enterFrame(event:Event):void { myCanvas.graphics.clear(); myCanvas.graphics.beginFill(0xFF344ff0); myCanvas.graphics.drawRect(myPoint.x,myPoint.y,40,40); myCanvas.graphics.endFill(); } public function onKeyDown(event:KeyboardEvent):void { myText.text = "Keycode is: " + event.keyCode + "\n"; switch(event.keyCode) { case 37: //Left myPoint.x -= 1; break; case 38: //Up myPoint.y -= 1; break; case 39: //Right myPoint.x += 1; break; case 40: //Down myPoint.y += 1; break; } } ]]> </mx:Script> </mx:Application>

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  • Drupal 6: Creating "ON/OFF News Links" functionality for a block created with View Module.

    - by artmania
    Hi friends, I'm a drupal newbie who needs some advice... I have a news list block at homepage, created with View Module. It is listing all added news' title and link. Everything is cool so far. Now I need to add an ON/OFF option at admin side for homepage news block. When the setting is ON, it will work as it is. When it is OFF, only the titles will be listed with no linking to news detail page. So, now where should I add this ON/OFF option? I have only add/edit/delete pages for each news, there is no common news page to add such option. Should I create an admin page with such ON/OFF option in? Also I think I need to create a db table to keep this ON/OFF status. and controlling this value at homepage block, if it is 1 or 0, and displaying links according to db value :/ it looks too long way Create db table Create an page with ON/OFF option in add php codes to update db for admin's choice get the db value in homepage block to display links, etc. is there any shorter, better way to do what I need? Appreciate helps so much!!! Thanks a lot!!

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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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  • Raspberry Pi broadcast serial port data to local network

    - by D051P0
    I didn't find anything to help me with this problem. What I want is: Serial device sends repeatedly some data to serial port. Raspberry Pi should get this data from RxD and stream it to local network via port 10001 without filtering it. So I can find this device on my pc. This should also work in other direction: Raspberry listen to port 10001 and forward all data from local network to TxD. I'm newbie in Linux World. How can I listen to some port on Raspberry Pi and send broadcast to the same port? I'm using Raspbian Wheezy with soft float. I have found a library Pi4j for Java, that I already use to get and write data from/to serial port. final Serial serial = SerialFactory.createInstance(); serial.addListener(new SerialDataListener() { public void dataReceived(SerialDataEvent event) { forward(event.getData()); } }); event.getData() is a String, which I want to broadcast in my local network. Is it generally a good Idea to use Java for that? I need also a String from port 10001, which I can forward to serial port.

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  • MySQL: optimization of table (indexing, foreign key) with no primary keys

    - by Haradzieniec
    Each member has 0 or more orders. Each order contains at least 1 item. memberid - varchar, not integer - that's OK (please do not mention that's not very good, I can't change it). So, thera 3 tables: members, orders and order_items. Orders and order_items are below: CREATE TABLE `orders` ( `orderid` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT, `memberid` VARCHAR( 20 ), `Time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP , `info` VARCHAR( 3200 ) NULL , PRIMARY KEY (orderid) , FOREIGN KEY (memberid) REFERENCES members(memberid) ) ENGINE = InnoDB; CREATE TABLE `order_items` ( `orderid` INT(11) UNSIGNED NOT NULL, `item_number_in_cart` tinyint(1) NOT NULL , --- 5 items in cart= 5 rows `price` DECIMAL (6,2) NOT NULL, FOREIGN KEY (orderid) REFERENCES orders(orderid) ) ENGINE = InnoDB; So, order_items table looks like: orderid - item_number_in_cart - price: ... 1000456 - 1 - 24.99 1000456 - 2 - 39.99 1000456 - 3 - 4.99 1000456 - 4 - 17.97 1000457 - 1 - 20.00 1000458 - 1 - 99.99 1000459 - 1 - 2.99 1000459 - 2 - 69.99 1000460 - 1 - 4.99 ... As you see, order_items table has no primary keys (and I think there is no sense to create an auto_increment id for this table, because once we want to extract data, we always extract it as WHERE orderid='1000456' order by item_number_in_card asc - the whole block, id woudn't be helpful in queries). Once data is inserted into order_items, it's not UPDATEd, just SELECTed. The questions are: I think it's a good idea to put index on item_number_in_cart. Could anybody please confirm that? Is there anything else I have to do with order_items to increase the performance, or that looks pretty good? I could miss something because I'm a newbie. Thank you in advance.

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  • Obj-C Sending Messages Between Classes

    - by user544359
    I'm a newbie in iPhone Programming. I'm trying to send a message from one view controller to another. The idea is that viewControllerA takes information from the user and sends it to viewControllerB. viewControllerB is then supposed to display the information in a label. viewControllerA.h #import <UIKit/UIKit.h> @interface viewControllerA : UIViewController { int num; } -(IBAction)do; @end viewControllerA.m #import "viewControllerA.h" #import "viewControllerB.h" @implementation viewControllerA - (IBAction)do { //initializing int for example num = 2; viewControllerB *viewB = [[viewControllerB alloc] init]; [viewB display:num]; [viewB release]; //viewA is presented as a ModalViewController, so it dismisses itself to return to the //original view, i know it is not efficient [self dismissModalViewControllerAnimated:YES]; } - (void)dealloc { [super dealloc]; } @end viewControllerB.h #import <UIKit/UIKit.h> @interface viewControllerB : UIViewController { IBOutlet UILabel *label; } - (IBAction)openA; - (void)display:(NSInteger)myNum; @end viewControllerB.m #import "viewControllerB.h" #import "viewControllerA.h" @implementation viewControllerB - (IBAction)openA { //presents viewControllerA when a button is pressed viewControllerA *viewA = [[viewControllerA alloc] init]; [self presentModalViewController:viewA animated:YES]; } - (void)display:(NSInteger)myNum { NSLog(@"YES"); [label setText:[NSString stringWithFormat:@"%d", myNum]]; } @end YES is logged successfully, but the label's text does not change. I have made sure that all of my connections in Interface Builder are correct, in fact there are other (IBAction) methods in my program that change the text of this very label, and all of those other methods work perfectly... Any ideas, guys? You don't need to give me a full solution, any bits of information will help. Thanks.

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