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  • How do I implement IEnumerable?

    - by Stacey
    I have a class that contains a static number of objects. This class needs to be frequently 'compared' to other classes that will be simple List objects. public partial class Sheet { public Item X{ get; set; } public Item Y{ get; set; } public Item Z{ get; set; } } the items are obviously not going to be "X" "Y" "Z", those are just generic names for example. The problem is that due to the nature of what needs to be done, a List won't work; even though everything in here is going to be of type Item. It is like a checklist of very specific things that has to be tested against in both code and runtime. This works all fine and well; it isn't my issue. My issue is iterating it. For instance I want to do the following... List<Item> UncheckedItems = // Repository Logic Here. UncheckedItems contains all available items; and the CheckedItems is the Sheet class instance. CheckedItems will contain items that were moved from Unchecked to Checked; however due to the nature of the storage system, items moved to Checked CANNOT be REMOVED from Unchecked. I simply want to iterate through "Checked" and remove anything from the list in Unchecked that is already in "Checked". So naturally, that would go like this with a normal list. foreach(Item item in Unchecked) { if( Checked.Contains(item) ) Unchecked.Remove( item ); } But since "Sheet" is not a 'List', I cannot do that. So I wanted to implement IEnumerable so that I could. Any suggestions? I've never implemented IEnumerable directly before and I'm pretty confused as to where to begin.

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  • .net remoting - Better solution to wait for a service to initialize ?

    - by CitizenInsane
    Context I have a client application (which i cannot modify, i.e. i only have the binary) that needs to run from time to time external commands that depends on a resource which is very long to initialize (about 20s). I thus decided to initialize this resource once for all in a "CommandServer.exe" application (single instance in the system tray) and let my client application call an intermediate "ExecuteCommand.exe" program that uses .net remoting to perform the operation on the server. The "ExecuteCommand.exe" is in charge for starting the server on first call and then leave it alive to speed up further commands. The service: public interface IMyService { void ExecuteCommand(string[] args); } The "CommandServer.exe" (using WindowsFormsApplicationBase for single instance management + user friendly splash screen during resource initializations): private void onStartupFirstInstance(object sender, StartupEventArgs e) { // Register communication channel channel = new TcpServerChannel("CommandServerChannel", 8234); ChannelServices.RegisterChannel(channel, false); // Register service var resource = veryLongToInitialize(); service = new MyServiceImpl(resource); RemotingServices.Marshal(service, "CommandServer"); // Create icon in system tray notifyIcon = new NotifyIcon(); ... } The intermediate "ExecuteCommand.exe": static void Main(string[] args) { startCommandServerIfRequired(); var channel = new TcpClientChannel(); ChannelServices.RegisterChannel(channel, false); var service = (IMyService)Activator.GetObject(typeof(IMyService), "tcp://localhost:8234/CommandServer"); service.RunCommand(args); } Problem As the server is very long to start (about 20s to initialize the required resources), the "ExecuteCommand.exe" fails on service.RunCommand(args) line because the server is yet not available. Question Is there a elegant way I can tune the delay before to receive "service not available" when calling service.RunCommand ? NB1: Currently I'm working around the issue by adding a mutex in server to indicate for complete initiliazation and have "ExecuteCommand.exe" to wait for this mutex before to call service.RunCommand. NB2: I have no background with .net remoting, nor WCF which is recommended replacer. (I chose .net remoting because this looked easier to set-up for this single shot issue in running external commands).

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  • Store data in tableview to NSUserDefaults

    - by Jozef Vrana
    Tricks.h file #import "Tricks.h" @implementation Tricks static NSMutableArray *trickList = nil; +(NSMutableArray *)trickList { if(!trickList){ trickList = [[NSMutableArray alloc]init]; } return trickList; } @end Tricks.m file @interface Tricks : NSObject @property(strong, nonatomic) NSString *trickName; Method for adding objects to array -(IBAction)saveAction:(id)sender { Tricks *trick = [[Tricks alloc]init]; trick.trickName = self.trickLabel.text; [[Tricks trickList]insertObject:trick atIndex:0]; [self.navigationController popViewControllerAnimated:YES]; } In .h file of UITabelview class I am making a reference to tricks class, but I am sure there is error on this line. @property (strong, nonatomic) Tricks *tricks; In cellForRow method I am storing data _trick = [[NSMutableDictionary alloc]initWithObjectsAndKeys:trick,nil]; NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults]; [defaults setObject:_trick forKey:@"numberArray"]; [defaults synchronize]; NSLog(@"%@",_trick); In .m class of UITableview in viewDidLoad I want to retrieve data if([[NSUserDefaults standardUserDefaults] objectForKey:@"numberArray"] != nil) { _tricks = [[NSUserDefaults standardUserDefaults] objectForKey:@"numberArray"]; } Thanks for advices

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  • GetLocalValueEnumerator() Not Returning All Properties

    - by a_hardin
    I am trying to perform validation in my WPF application using the solution in Detecting WPF Validation Errors. public static bool IsValid(DependencyObject parent) { // Validate all the bindings on the parent bool valid = true; LocalValueEnumerator localValues = parent.GetLocalValueEnumerator(); while (localValues.MoveNext()) { LocalValueEntry entry = localValues.Current; if (BindingOperations.IsDataBound(parent, entry.Property)) { Binding binding = BindingOperations.GetBinding(parent, entry.Property); foreach (ValidationRule rule in binding.ValidationRules) { ValidationResult result = rule.Validate(parent.GetValue(entry.Property), null); if (!result.IsValid) { BindingExpression expression = BindingOperations.GetBindingExpression(parent, entry.Property); System.Windows.Controls.Validation.MarkInvalid(expression, new ValidationError(rule, expression, result.ErrorContent, null)); valid = false; } } } } // Validate all the bindings on the children for (int i = 0; i != VisualTreeHelper.GetChildrenCount(parent); ++i) { DependencyObject child = VisualTreeHelper.GetChild(parent, i); if (!IsValid(child)) { valid = false; } } return valid; } The problem I am running into is that when I step through the code for a TextBox, I'm not getting the Text property. The only properties I get are "PageHeight", "Instance", and "UndoManagerInstance". Therefore, I can not Validate the rules for the binding on the TextBox. Does anyone have any idea why I wouldn't be getting the correct properties? Is there another way to force validaton on controls in WPF? I haven't been able to find anyone else who has had this problem. Update: The TextBoxes I am trying to validate are within a DataTemplate. I found that if I copy one of the TextBoxes and place it directly in the Window, I am able to get the data. Using Woodstock, I saw that the data source for the TextBoxes in the template is "ParentTemplate", but it's "Local" for the TextBox outside of the template. So, the question now is, how can I get the DependencyProperties for controls inside a DataTemplate?

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  • Simulate Golf Game Strategy

    - by Mitchel Sellers
    I am working on what at best could be considered a "primitive" golf game, where after a certain bit of randomness is introduced I need to play out a hole of golf. The hole is static and I am not concerned about the UI aspect as I just have to draw a line on a graphic of the hole after the ball has been hit showing where it traveled. I'm looking for input on thoughts of how to manage the "logic" side of the puzzle, below are some of my thoughts on the matter, input, suggestions, or references are greatly appreciated. Map out the hole into an array with a specific amount of precision, noting the type of surface: out of bounds, fairway, rough, green, sand, water, and most important the hole. Map out "regions" and if the ball is contained inside one of these regions setup parameters for "maximum" angle of departure. (For example the first part of the hole the shot must be between certain angles Using the current placement of the ball, and the region contained in #2, define a routine to randomly select the shooting angle, and power then move the ball, adjust the trajectory and move again. I know this isn't the "most elegant" solution, but in reality, we are looking for a quick and dirty solution, as I just have to do this a few times, set it and forget it afterward. From a languages perspective I'll be using ASP.NET and C# to get this done.

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  • Scope of Groovy's ExpandoMetaClass?

    - by TicketMonster
    Groovy exposes an ExpandoMetaClass that allows you to dynamically add instance and class methods/properties to a POJO. I would like to use it to add an instance method to one of my Java classes: public class Fizz { // ...etc. } Fizz fizz = new Fizz(); fizz.metaClass.doStuff = { String blah -> fizz.buzz(blah) } This would be the equivalent to refactoring the Fizz class to have: public class Fizz { // ctors, getters/setters, etc... public void doStuff(String blah) { buzz(blah); } } My question: Does this add doStuff(String blah) to only this particular instance of Fizz? Or do all instances of Fizz now have a doStuff(String blah) instance method? If the former, how do I get all instances of Fizz to have the doStuff instance method? I know that if I made the Groovy: fizz.metaClass.doStuff << { String blah -> fizz.buzz(blah) } Then that would add a static class method to Fizz, such as Fizz.doStuff(String blah), but that's not what I want. I just want all instances of Fizz to now have an instance method called doStuff. Ideas?

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  • How to use the values from session variables in jsp pages that got saved using @Scope("session") in the mvc controllers

    - by droidsites
    Doing a web site using spring mvc. I added a SignupController to handle all the sign up related requests. Once user signup I am adding that to a session using @Scope("session"). Below is the SignupController code, SignupController.java @Controller @Scope("session") public class SignupController { @Autowired SignupServiceInter signUpService; private static final Logger logger = Logger.getLogger(SignupController.class); private String sessionUser; @RequestMapping("/SignupService") public ModelAndView signUp(@RequestParam("userid") String userId, @RequestParam("password") String password,@RequestParam("mailid") String emailId){ logger.debug(" userId:"+userId+"::Password::"+password+"::"); String signupResult; try { signUpService.registerUser(userId, password,emailId); sessionUser = userId; //adding the sign up user to the session return new ModelAndView("userHomePage","loginResult","Success"); //Navigate to user Home page if everything goes right } catch (UserExistsException e) { signupResult = e.toString(); return new ModelAndView("signUp","loginResult", signupResult); //Navigate to signUp page back if user does not exist } } } I am using "sessionUser" variable to store the signed up User Id. My understanding is that when I use @Scope("session") for the controller all the instance variables will added to HttpSession. So by that understanding I tried to access this "SessionUser" in userHomePage.jsp as, userHomepage.jsp Welcome to <%=session.getAttribute("sessionUser")%> But it throws null. So my question is how to use the values from session variables in jsp pages that got saved using @Scope("session") in the mvc controllers. Note: My work around is that pass that signed User Id to jsp page through ModelAndView, but it seems passing the value like these among the pages takes me back to managing state among pages using QueryStrings days.

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  • Getting array of Values of Textboxes with the same class

    - by nCdy
    I setup custom CSS class for array of dynamic TextBoxes (inputs as HTML) so... now I need to get array of it : <input type="text" style="width: 50px;" class="DynamicTB" id="ctl00_ContentPlaceHolder1_GridView1_ctl02_id" readonly="readonly" value="1" name="ctl00$ContentPlaceHolder1$GridView1$ctl02$id"> sure client don't really knows the count of inputs. That's why I use class and here is what I'm trying to make : $.each( { id : $("input.DynamicTB").css("value") }, function(id){ CallPageMethod("SelectBook", success, fail, "id",id); }); I'm not sure if this $("input.DynamicTB").css("value") will works correct :( but How can I transfer whole array of values to SelectBook Method ? My javascript is bad and my debugger don't show me javascript errors but it just doesn't works because of something wrong with each. And ... finally I just need to get array of values of dynamic textboxes and transfer them to server side ... mt [WebMethode] can't see server side :( [Web.Services.WebMethod] public static SelectBook(id : array) : string { id } And sure I have no idea how can I use jQuery .live and binding here.

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  • How to customize file dialog in wpf

    - by ManjuAnoop
    In Windows7 I am using a customized Open File Dialog( WPF application). My Open File dialog is derived from Microsoft.Win32.CommonDialog. The dialog have old look, how to change this to new look (windows7 file dialog look(Explorer style)). Code portion: private const int OFN_ENABLESIZING = 0x00800000; private const int OFN_EXPLORER = 0x00080000; private const int OFN_ENABLEHOOK = 0x00000020; protected override bool RunDialog(IntPtr hwndOwner) { OPENFILENAME_I.WndProc proc = new OPENFILENAME_I.WndProc(this.HookProc); OPENFILENAME_I ofn = new OPENFILENAME_I(); this._charBuffer = CharBuffer.CreateBuffer(0x2000); if (this._fileNames != null) { this._charBuffer.PutString(this._fileNames[0]); } ofn.lStructSize = Marshal.SizeOf(typeof(OPENFILENAME_I)); ofn.hwndOwner = hwndOwner; ofn.hInstance = IntPtr.Zero; ofn.lpstrFilter = MakeFilterString(this._filter, this.DereferenceLinks); ofn.nFilterIndex = this._filterIndex; ofn.lpstrFile = this._charBuffer.AllocCoTaskMem(); ofn.nMaxFile = this._charBuffer.Length; ofn.lpstrInitialDir = this._initialDirectory; ofn.lpstrTitle = this._title; ofn.Flags = OFN_EXPLORER | OFN_ENABLESIZING | OFN_ENABLEHOOK; ofn.lpfnHook = proc; ofn.FlagsEx = 0x1000000 ; NativeMethods.GetOpenFileName(ofn); // } [SecurityCritical, SuppressUnmanagedCodeSecurity, DllImport("comdlg32.dll", CharSet = CharSet.Unicode, SetLastError = true)] internal static extern bool GetOpenFileName([In, Out] OPENFILENAME_I ofn);

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  • Python: Sorting array with custom pattern

    - by Binka
    In my little project here I have sorted a list in decending order, however, my goal is to sort it in this custom pattern. (largest - smallest - next largest - next smallest -)etc. In java I was able to do this like this... My goal is to do the same thing but in python, except backwards. Any ideas on how to convert that last for loop that does the wackysort into python and make it go backwards? public static void wackySort(int[] nums){ //first, this simply sorts the array by ascending order. int sign = 0; int temp = 0; int temp2 = 0; for (int i = 0; i < nums.length; i++){ for (int j = 0; j < nums.length -1; j++){ if (nums[j] > nums[j+1]){ temp = nums[j]; nums[j] = nums[j+1]; nums[j+1] = temp; } } } //prepare for new array to actually do the wacky sort. System.out.println(); int firstPointer = 0; int secondPointer = nums.length -1; int[] newarray = new int[nums.length]; int size = nums.length; //for loop that increments by two taking second slot replacing the last (n-1) term for (int i = 0; i < nums.length -1; i+=2){ newarray[i] = nums[firstPointer++]; newarray[i+1] = nums[secondPointer--]; } //storing those values back in the nums array for (int i = 0; i < nums.length; i++){ nums[i] = newarray[i]; } }

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  • java packets byte

    - by user303289
    Guys, I am implementing a protocol in one of the wireless project. I am stucked at one point. In of the java file i am suppose to receive a packet and that packet is 12 byte packet and I have to write different functions for reading different parts of packets and convert it to diferent type. Like I want first four byte in one of the function and convert it to int, next two bytes in string. and again next two in string, last two hop in string and followed by last two int. I want follwing function to implement: // here is the interface /* FloodingData should use methods defined in this class. */ class FloodingPacket{ public static void main(String arg[]){ byte FloodingPack[]; // just for example to test in code FloodingPack=new byte[12]; interface IFloodingPacket { // Returns the unique sequence number for the packet int getSequenceNumber() ; // Returns the source address for the packet String getSourceAddress(); // Returns the destination address for the packet String getDestinationAddress(); // Returns the last hop address for the packet String getLastHopAddress(); // Sets the last hop address to the address of the node // which the packet was received from void updateLastHopAddress(); // Returns the entire packet in bytes (for sending) byte[] getBytes(); // Sets the bytes of the packet (for receiving) void setBytes(byte[] packet); }

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  • need help with some basic java.

    - by Racket
    Hi, I'm doing the first chapter exercises on my Java book and I have been stuck for a problem for a while now. I'll print the question, prompt/read a double value representing a monetary amount. Then determine the fewest number of each bill and coin needed to represent that amount, starting with the highest (assume that a ten dollar bill is the maximum size needed). For example, if the value entered is 47,63 (forty-seven dollars and sixty-three cents), and the program should print the equivalent amount as: 4 ten dollar bills 1 five dollar bills 2 one dollar bills 2 quarters 1 dimes 0 nickels 3 pennies" etc. I'm doing an example exactly as they said in order to get an idea, as you will see in the code. Nevertheless, I managed to print 4 dollars, and I can't figure out how to get "1 five dollar", only 7 dollars (see code). Please, don't do the whole code for me. I just need some advice in regards to what I said. Thank you. import java.util.Scanner; public class PP29 { public static void main (String[] args) { Scanner sc = new Scanner (System.in); int amount; double value; double test1; double quarter; System.out.println("Enter \"double\" value: "); value = sc.nextDouble(); amount = (int) value / 10; // 47,63 / 10 = 4. int amount2 = (int) value % 10; // 47 - 40 = 7 quarter = value * 100; // 47,63 * 100 = 4736 int sum = (int) quarter % 100; // 4763 / 100 => 4763-4700 = 63. System.out.println(amount); System.out.println(amount2); } }

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  • Website hosting from home - IIS6 [closed]

    - by Paul
    I'm wanting to host a few websites from home, primarily because I'm using some BETA Microsoft software (.NET 4 and EF) and don't want to install it on my production server which is hosted at eukhost.com. Basically, I'm completely new to this sort of thing. So far, here is what I've done: Registered the domain name at namecheap.com (let's call it mydomain.com) Gone to "Nameserver Registration" in the panel and entered my IP address for the NS1 and NS2 records (let's say the IP is 0.0.0.0). Gone to "Domain Name Server Setup" and entered ns1.mydomain.com & ns2.mydomain.com Forwarded requests from port 80 to my internal IP (let's say 192.168.1.254) Created the website in IIS (I'm just testing with a single website so far, so have not created any host header values) Now, if I type in the IP address (http://0.0.0.0) I get the site as expected. However, if I enter http://www.mydomain.com I get an error saying "DNS Error - Cannot find server". I'm aware that there is a service from DynDNS that will automatically change the IP if I have a dynamic address, however my IP has remained static since I installed the ISP (since October) so I don't need this. Is there any way that I can get the DNS to work just by configuring IIS or something in Windows? I don't really want to have to pay for any 3rd party service. Thanks,

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  • What is my error in a map in java?

    - by amveg
    Hello everyone I am trying to solve this problem: http://www.cstutoringcenter.com/problems/problems.php?id=4, but I cant figure out why my code doesnt solve this, I mean in the "for" how can I can multiply the letters? what is my error?, It just tell always 7, but I want to multiple all the letters, I hope you can help me enter code here public class ejercicio3 { public static void main(String args[]) { Map<Character, Integer> telefono = new HashMap<Character, Integer>(); telefono.put('A', 2); telefono.put('B', 2); telefono.put('C', 2); telefono.put('D', 3); telefono.put('E', 3); telefono.put('F', 3); telefono.put('G', 4); telefono.put('H', 4); telefono.put('I', 4); telefono.put('J', 5); telefono.put('K', 5); telefono.put('L', 5); telefono.put('M', 6); telefono.put('N', 6); telefono.put('O', 6); telefono.put('P', 7); telefono.put('R', 7); telefono.put('S', 7); telefono.put('T', 8); telefono.put('U', 8); telefono.put('V', 8); telefono.put('W', 9); telefono.put('X', 9); telefono.put('Y', 9); String mensaje = "Practice"; int producto = 1; for (char c : mensaje.toCharArray()) { if (telefono.containsKey(c)) { producto = telefono.get(c) * producto; System.out.println(producto); } } } }

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  • "Syntax error in INSERT INTO statement". Why?

    - by Kevin
    My code is below. I have a method where I pass in three parameters and they get written out to an MS Access database table. However, I keep getting a syntax error message. Can anyone tell me why? I got this example from the internet. private static void insertRecord(string day, int hour, int loadKW) { string connString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\LoadForecastDB.accdb"; OleDbConnection conn = new OleDbConnection(connString); string ins = @"INSERT INTO Forecasts (Day, Hour, Load) VALUES (?,?,?)"; OleDbCommand cmd = new OleDbCommand(ins, conn); cmd.Parameters.Add("@day", OleDbType.VarChar).Value = day; cmd.Parameters.Add("@hour", OleDbType.Integer).Value = hour; cmd.Parameters.Add("@load", OleDbType.Integer).Value = loadKW; conn.Open(); try { int count = cmd.ExecuteNonQuery(); } catch (OleDbException ex) { Console.WriteLine(ex.Message); } finally { conn.Close(); } }

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  • Problem in arranging contents of Class in JAVA

    - by LuckySlevin
    Hi, I have some classes and I'm trying to fill the objects of this class. Here is what i've tried. (Question is at the below) public class Team { private String clubName; private String preName; private ArrayList<String> branches; public Team(String clubName, String preName) { this.clubName = clubName; this.preName = preName; branches = new ArrayList<String>(); } public Team() { // TODO Auto-generated constructor stub } public String getClubName() { return clubName; } public String getPreName() { return preName; } public ArrayList<String> getBranches() { return branches; } public void setClubName(String clubName) { this.clubName = clubName; } public void setPreName(String preName) { this.preName = preName; } public void setBranches(ArrayList<String> branches) { this.branches = branches; } } public class Branch { private ArrayList<Player> players = new ArrayList<Player>(); String brName; public Branch() {} public void setBr(String brName){this.brName = brName;} public String getBr(){return brName;} public ArrayList<Player> getPlayers() { return players; } public void setPlayers(ArrayList<Player> players) { this.players = players; } } //TEST CLASS public class test { /** * @param args * @throws IOException */ public static void main(String[] args) throws IOException { String a,b,c; String q = "q"; int brCount = 0, tCount = 0; BufferedReader input = new BufferedReader(new InputStreamReader(System.in)); Team[] teams = new Team[30]; Branch[] myBranch = new Branch[30]; for(int z = 0 ; z <30 ;z++) { teams[z] = new Team(); myBranch[z] = new Branch(); } ArrayList<String> tmp = new ArrayList<String>(); int k = 0; int secim = Integer.parseInt(input.readLine()); while(secim != 0) { if(k!=0) secim = Integer.parseInt(input.readLine()); k++; switch(secim) { case 1 : brCount = 0; a = input.readLine(); teams[tCount].setClubName(a); b= input.readLine(); teams[tCount].setPreName(b); c = input.readLine(); while(c.equals(q) == false) { if(brCount != 0) {c = input.readLine();} if(c.equals(q)== false){ myBranch[brCount].brName = c; tmp.add(myBranch[brCount].brName); brCount++; } System.out.println(brCount); } teams[tCount].setBranches(tmp); for(int i=0;i<=tCount;i++ ){ System.out.print("a :" + teams[i].getClubName()+ " " + teams[i].getPreName()+ " "); System.out.println(teams[i].getBranches());} tCount++; break; case 2: String src = input.readLine();//LATERRRRRRRr } } } } The problem is one of my class elements. I have an arraylist as an element of a class. When i enter: AAA as preName BBB as clubName c d e as Branches Then as a second element www as preName GGG as clubName a b as branches The result is coming like: AAA BBB c,d,e,a,b GGG www c,d,e,a,b Which means ArrayList part of the class is putting it on and on. I tried to use clear() method but caused problems. Any ideas.

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  • android: error on SQLiteDatabase rawQuery (fetching data)

    - by Jin
    So I have a SQliteDatabase mDb. It only has one column, and its data are Strings for previously saved inputs. I'm trying to populate all the data from mDb into a String[] for AutoCompleteTextView (so that the autocomplete is based on previous inputs), and here's my code to get all of the String. public String[] fetchAllSearch() { ArrayList<String> allSearch = new ArrayList<String>(); Cursor c = mDb.rawQuery("select * from " + DATABASE_TABLE, null); c.moveToFirst(); if (c.getCount() > 0) { do { allSearch.add(c.getString(c.getColumnIndex("KEY"))); } while (c.moveToNext()); } String[] foo = (String[]) allSearch.toArray(); if (foo == null) { foo = new String[] {""}; } return foo; } my CREATE_TABLE command is private static final String DATABASE_CREATE = "create table " + DATABASE_TABLE; .. public void onCreate(SQLiteDatabase db) { db.execSQL(DATABASE_CREATE); } But for some reason the line mDb.rawQuery(...) is giving me "no such table found" exception, and for the life of me I can't figure out why. Any pointers?

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  • How is covariance cooler than polymorphism...and not redundant?

    - by P.Brian.Mackey
    .NET 4 introduces covariance. I guess it is useful. After all, MS went through all the trouble of adding it to the C# language. But, why is Covariance more useful than good old polymorphism? I wrote this example to understand why I should implement Covariance, but I still don't get it. Please enlighten me. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Sample { class Demo { public delegate void ContraAction<in T>(T a); public interface IContainer<out T> { T GetItem(); void Do(ContraAction<T> action); } public class Container<T> : IContainer<T> { private T item; public Container(T item) { this.item = item; } public T GetItem() { return item; } public void Do(ContraAction<T> action) { action(item); } } public class Shape { public void Draw() { Console.WriteLine("Shape Drawn"); } } public class Circle:Shape { public void DrawCircle() { Console.WriteLine("Circle Drawn"); } } public static void Main() { Circle circle = new Circle(); IContainer<Shape> container = new Container<Circle>(circle); container.Do(s => s.Draw());//calls shape //Old school polymorphism...how is this not the same thing? Shape shape = new Circle(); shape.Draw(); } } }

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  • How to correctly pass a float from C# to C++ (dll)

    - by RavelT
    I'm getting huge differences when I pass a float from C# to C++. I'm passing a dynamic float wich changes over time. With a debuger I get this: c++ lonVel -0.036019072 float c# lonVel -0.029392920 float I did set my MSVC++2010 floating point model to /fp:fast wich should be the standard in .NET if I'm not mistaken, but this didnt help. Now I cant give out the code but I can show a fraction of it. From C# side it looks like this: namespace Example { public class Wheel { public bool loging = true; #region Members public IntPtr nativeWheelObject; #endregion Members public Wheel() { this.nativeWheelObject = Sim.Dll_Wheel_Add(); return; } #region Wrapper methods public void SetVelocity(float lonRoadVelocity,float latRoadVelocity){Sim.Dll_Wheel_SetVelocity(this.nativeWheelObject,lonRoadVelocity,latRoadVelocity);} #endregion Wrapper methods } internal class Sim { #region PInvokes [DllImport(pluginName, CallingConvention=CallingConvention.Cdecl)] public static extern void Dll_Wheel_SetVelocity(IntPtr wheel,float lonRoadVelocity,float latRoadVelocity); #endregion PInvokes } } And in C++ side @ exportFunctions.cpp: EXPORT_API void Dll_Wheel_SetVelocity(CarWheel* wheel,float lonRoadVelocity,float latRoadVelocity){ wheel->SetVelocity(lonRoadVelocity,latRoadVelocity);} So any sugestions on what I should do in order to get 1:1 results or atleast 99% correct results.

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  • Tips on refactoring an Android prototype

    - by Brad
    I have an Android project I've inherited from another developer. The original code was hacked together using a single View and a single Activity. The view class has a State variable that is switched on during input and rendering. Each "screen" is a single bitmap rendered directly onto the screen. There are no layouts used at all. To make things even worse each variable in both the View and Activity classes were all declared public static and would access each other frequently. I've reworked the code so it is now somewhat manageable, but it's still in those original two classes. This is my first decently sized Android app so I'm not completely sure where to go next. From the looks of things, each "screen" should have its own View and Activity. Is this the general practice? If so I need some way to share data between the separate Activities. I've read suggestions to use a Singleton class that holds generic data. Is there any other ways that are more built into the Android framework? Thanks in advance.

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  • C++ - Totally suspend windows application

    - by HardCoder1986
    Hello! I am developing a simple WinAPI application and started from writing my own assertion system. I have a macro defined like ASSERT(X) which would make pretty the same thing as assert(X) does, but with more information, more options and etc. At some moment (when that assertion system was already running and working) I realized there is a problem. Suppose I wrote a code that does some action using a timer and (just a simple example) this action is done while handling WM_TIMER message. And now, the situation changes the way that this code starts throwing an assert. This assert message would be shown every TIMER_RESOLUTION milliseconds and would simply flood the screen. Options for solving this situation could be: 1) Totally pause application running (probably also, suspend all threads) when the assertion messagebox is shown and continue running after it is closed 2) Make a static counter for the shown asserts and don't show asserts when one of them is already showing (but this doesn't pause application) 3) Group similiar asserts and show only one for each assert type (but this also doesn't pause application) 4) Modify the application code (for example, Get / Translate / Dispatch message loop) so that it suspends itself when there are any asserts. This is good, but not universal and looks like a hack. To my mind, option number 1 is the best. But I don't know any way how this can be achieved. What I'm seeking for is a way to pause the runtime (something similiar to Pause button in the debugger). Does somebody know how to achieve this? Also, if somebody knows an efficient way to handle this problem - I would appreciate your help. Thank you.

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  • What 20 Lines (or less) of code did you find really useful?

    - by Ygam
    You can share your code or other's code. Here's a snippet from an array function in Kohana: public static function rotate($source_array, $keep_keys = TRUE) { $new_array = array(); foreach ($source_array as $key => $value) { $value = ($keep_keys === TRUE) ? $value : array_values($value); foreach ($value as $k => $v) { $new_array[$k][$key] = $v; } } return $new_array; } It was helpful when I was uploading multiple images using multiple file upload forms. It turned this array array('images' => array( 'name' => array( 0 => 'img1', 1 => 'img0', 2 =>'img2' ), 'error' => array( 0 => '', 1 => '', 2 => '' into : array('images' => array( 0 => array( 'name' => 'img1' 'error' => '' ),//rest goes here How about you? What 20 or less lines of code did you find useful?

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  • Handling return value from Web Service Call Wrapper

    - by coffeeaddict
    I created this method below which makes an HTTP call to a 3rd party API. I just want opinions on if I'm handling this the best way. If the call fails, I need to return the ExistsInList bool value only if the response is not null. But in the last return statement, wouldn't I have to essentially do another return selectResponse == null ? false : selectResponse.ExistsInList; to check for null first just like the previous return in the catch? Just seems redundant the way I'm approaching this and I don't know if I really need to check for null again in the final return but I figure yes, because you can't always rely on the response to give you a valid response even if there were no errors picked up. public static bool UserExistsInList(string email, string listID) { SelectRecipientRequest selectRequest = new SelectRecipientRequest(email, listID); SelectRecipientResponse selectResponse = null; try { selectResponse = (SelectRecipientResponse)selectRequest.SendRequest(); } catch (Exception) { return selectResponse == null ? false : selectResponse.ExistsInList; } return selectResponse.ExistsInList; }

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  • how to clear a data in tableviewcell again start reload?

    - by Ios_learner
    i'm developing a bluetooth apps.1) I want to hide a tableview when i start the apps..after i pressed a action button i want to enable a tableview.. 2)if i again press a action button means tableviewcell clear the data and show empty before searching..give me an idea.. some of the code- - (IBAction)connectButtonTouched:(id)sender { [self.deviceTable reloadData]; self.connectButton.enabled = YES; [self.deviceTable reloadData]; peripheralManager = [[PeripheralManager alloc] init]; peripheralManager.delegate = self; [peripheralManager scanForPeripheralsAndConnect]; [self.deviceTable reloadData]; [NSTimer scheduledTimerWithTimeInterval:(float)5.0 target:self selector:@selector (connectionTimer:) userInfo:nil repeats:YES]; alert=[[UIAlertView alloc] initWithTitle:@"Bluetooth" message:@"Scanning" delegate:nil cancelButtonTitle:@"Cancel" otherButtonTitles:nil]; UIActivityIndicatorView *progress=[[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(125, 50, 30, 30)]; [alert addSubview:progress]; [progress startAnimating]; [alert show]; } tableview -(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } -(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [device count]; } -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier=@"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if(cell==nil) { cell =[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]; } cell.textLabel.text=[device objectAtIndex:indexPath.row]; cell.accessoryType=UITableViewCellAccessoryDetailDisclosureButton; return cell; } TableView Delegate - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { UITableViewCell *cell=[tableView cellForRowAtIndexPath:indexPath]; [self performSegueWithIdentifier:@"TableDetails" sender:tableView]; }

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  • how to merge two ordered list of objects?

    - by bhavna raghuvanshi
    public class ListMerge { public static void main( String[] args) { Scanner input = new Scanner(System.in); System.out.println ("Input length of arraylist 1:"); int n = input.nextInt(); ArrayList x = new ArrayList(); ArrayList y = new ArrayList(); for (int i = 0; i < n; i++) { System.out.println ("Input x[ " + i +"] :" ); x.add(new Integer(i)); } System.out.println ("Input length of arraylist 2:"); int m = input.nextInt(); for (int i = 0; i < m; i++) { System.out.println ("Input y[ " + i +"] :" ); y.add(new Integer(i)); } List<Integer> all = new ArrayList<Integer>(); all.addAll(x); all.addAll(y); System.out.println(all); } } I did this but its not taking values from user. pls tell me why....

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