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  • Problem with SqlLite database in Qt SDK 1.0.2

    - by Risino
    Hi I have a problem with SqlLite database. Here is my code: void incomeDialog::on_add_pushButton_clicked() { int a = ui->income_lineEdit->text().toInt(); int b = ui->other_lineEdit->text().toInt(); int c = (a+b); db = QSqlDatabase::addDatabase("QSQLITE"); db.setDatabaseName("money.db"); QSqlQuery query(db); query.exec("create table Income" "(Month TEXT, Payment NUMBER, Other NUMBER, Together NUMBER)"); query.prepare("INSERT INTO Income values (?,?,?,?)"); query.addBindValue(ui->comboBox->currentText()); query.addBindValue(ui->income_lineEdit->text().toInt()); query.addBindValue(ui->other_lineEdit->text().toInt()); query.addBindValue(c); query.exec(); } I use qt sdk 1.0.2. After building shows errors: Undefined reference to 'QSqlDatabase::addDatabase(QString const&, QString const&)... all errors is similar (Undefined reference to 'QSqlDatabase:: Do you have any idea how to repair it?

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  • VB.net/Excel- "Backwards" tab index For Each iteration with textboxes.

    - by MSD
    Hi there, I have a form with 3 textboxes and 1 button. textbox1 has tab index 0, and it's text = 1 textbox2 has tab index 1, and it's text = 2 textbox3 has tab index 2, and it's text = 3 I want to iterate thru the textboxes and place their values into cells so that... range("A1").value = txtbox1.text (ie: A1 = "1") range("A2").value = txtbox2.text (ie: A2 = "2") range("A3").value = txtbox3.text (ie: A3 = "3") but what I am getting is... range("A1").value = txtbox1.text (ie: A1 = "3") range("A2").value = txtbox2.text (ie: A2 = "2") range("A3").value = txtbox3.text (ie: A3 = "1") I have tried reversing the tab index for the text boxes, but it doesn't change the "backwards iteration". Is there something I can do to change this so that the loop runs from lowest tab index to highest? Thanks! Public Class Form1 Private Sub Button1_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim objExcel As New Microsoft.Office.Interop.Excel.Application 'Declaring the object. objExcel.Visible = True 'Setting Excel to visible. Dim cntrl As Control With objExcel .Workbooks.Add() 'Adding a workbook. .Range("A1").Select() 'Selecting cell A1. End With 'Form contains 3 text boxes, with one number in each (1,2,3), and one button to fire the code in this sub. For Each cntrl In Me.Controls 'For every control on the form... If TypeOf (cntrl) Is TextBox Then 'If the control is a textbox, then... With objExcel .ActiveCell.Value = cntrl.Text 'place the control's text in the active cell and... .ActiveCell.Offset(1, 0).Activate() 'offset down one row. End With End If 'If the control is not a textbox (if it's the button), do nothing. Next 'Go to the next control. objExcel = Nothing 'Release the object. GC.Collect() 'Clean up. End Sub End Class

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  • no longer an issue

    - by MrTemp
    I am still new to c# and wpf This program is a clock with different view and I would like to use the context menu to change between view, but the error says that there is no definition or extension method for the events. Right now I have the event I'm working on popping up a MessageBox just so I know it has run, but I cannot get it to compile. public partial class MainWindow : NavigationWindow { public MainWindow() { //InitializeComponent(); } public void AnalogMenu_Click(object sender, RoutedEventArgs e) { /*AnalogClock analog = new AnalogClock(); this.NavigationService.Navigate(analog);*/ } public void DigitalMenu_Click(object sender, RoutedEventArgs e) { MessageBox.Show("Digital Clicked"); /*DigitalClock digital = new DigitalClock(); this.NavigationService.Navigate(digital);*/ } public void BinaryMenu_Click(object sender, RoutedEventArgs e) { /*BinaryClock binary = new BinaryClock(); this.NavigationService.Navigate(binary);*/ } } and the xaml call if you want it <NavigationWindow.ContextMenu> <ContextMenu Name="ClockMenu" > <MenuItem Name="ToAnalog" Header="To Analog" ToolTip="Changes to an analog clock"/> <MenuItem Name="ToDigital" Header="To Digital" ToolTip="Changes to a digital clock" Click="DigitalMenu_Click" /> <MenuItem Name="ToBinary" Header="To Binary" ToolTip="Changes to a binary clock"/> </ContextMenu> </NavigationWindow.ContextMenu>

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  • Django Getting RequestContext in custom tag

    - by greggory.hz
    I'm trying to create a custom tag. Inside this custom tag, I want to be able to have some logic that checks if the user is logged in, and then have the tag rendered accordingly. This is what I have: class UserActionNode(template.Node): def __init__(self): pass def render(self, context): if context.user.is_authenticated(): return render_to_string('layout_elements/sign_in_register.html'); else: return render_to_string('layout_elements/logout_settings.html'); def user_actions(parser, test): return UserActionNode() register.tag('user_actions', user_actions) When I run this, I get this error: Caught AttributeError while rendering: 'Context' object has no attribute 'user' The view that renders this looks like this: return render_to_response('start/home.html', {}, context_instance=RequestContext(request)) Why doesn't the tag get a RequestContext object instead of the Context object? How can I get the tag to receive the RequestContext instead of the Context? EDIT: Whether or not it's possible to get a RequestContext inside a custom tag, I'd still be interested to know the "correct" or best way to determine a user's authentication state from within the custom tag. If that's not possible, then perhaps that kind of logic belongs elsewhere? Where?

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  • Symfony 2 - Updating a table based on newly inserted record in another table

    - by W00d5t0ck
    I'm trying to create a small forum application using Symfony 2 and Doctrine 2. My ForumTopic entity has a last_post field (oneToOne mapping). Now when I persist my new post with $em->persist($post); I want to update my ForumTopic entity so its last_post field would reference this new post. I have just realised that it cannot be done with a Doctrine postPersist Listener, so I decided to use a small hack, and tried: $em->persist($post); $em->flush(); $topic->setLastPost($post); $em->persist($post); $em->flush(); but it doesn't seem to update my topics table. I also took a look at http://docs.doctrine-project.org/projects/doctrine-orm/en/2.1/reference/working-with-associations.html#transitive-persistence-cascade-operations hoping it will solve the problem by adding cascade: [ 'persist' ] to my Topic.orm.yml file, but it didn't help, either. Could anyone point me to a solution or an example class? My ForumTopic is: FrontBundle\Entity\ForumTopic: type: entity table: forum_topics id: id: type: integer generator: strategy: AUTO fields: title: type: string(100) nullable: false slug: type: string(100) nullable: false created_at: type: datetime nullable: false updated_at: type: datetime nullable: true update_reason: type: text nullable: true oneToMany: posts: targetEntity: ForumPost mappedBy: topic manyToOne: created_by: targetEntity: User inversedBy: articles nullable: false updated_by: targetEntity: User nullable: true default: null topic_group: targetEntity: ForumTopicGroup inversedBy: topics nullable: false oneToOne: last_post: targetEntity: ForumPost nullable: true default: null cascade: [ persist ] uniqueConstraint: uniqueSlugByGroup: columns: [ topic_group, slug ] And my ForumPost is: FrontBundle\Entity\ForumPost: type: entity table: forum_posts id: id: type: integer generator: strategy: AUTO fields: created_at: type: datetime nullable: false updated_at: type: datetime nullable: true update_reason: type: string nullable: true text: type: text nullable: false manyToOne: created_by: targetEntity: User inversedBy: forum_posts nullable: false updated_by: targetEntity: User nullable: true default: null topic: targetEntity: ForumTopic inversedBy: posts

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  • c# template member functions

    - by user3730583
    How can I define a template member function in C# For instance I will fill any collection which supports an Add(...) member function, please check out the sample code below public class CInternalCollection { public static void ExternalCollectionTryOne<T<int>>(ref T<int> ext_col, int para_selection = 0) { foreach (int int_value in m_int_col) { if (int_value > para_selection) ext_col.Add(int_value); } } public static void ExternalCollectionTryTwo<T>(ref T ext_col, int para_selection = 0) { foreach (int int_value in m_int_col) { if (int_value > para_selection) ext_col.Add(int_value); } } static int[] m_int_col = { 0, -1, -3, 5, 7, -8 }; } The ExternalCollectionTryOne<...(...) would be the preferred kind, because the int type can be explicit defined, but results in an error: Type parameter declaration must be an identifier not a type The type or namespace name 'T' could not be found (are you missing a using directive or an assembly reference?) The ExternalCollectionTryTwo<...(...) results in an error: 'T' does not contain a definition for 'Add' and no extension method 'Add' accepting a first argument of type 'T' could be found (are you missing a using directive or an assembly reference?)... I hope the problem is clear – any suggestions? ----------------------------- edit -------------------------- The answers with the interface ICollection<.. without a template member works fine and thanks all for this hint, but I still cannot define successfully a member template(generic) function So a more simpler example ... how can I define this public class CAddCollectionValues { public static void AddInt<T>(ref T number, int selection) { T new_T = new T(); //this line is just an easy demonstration to get a compile error with type T foreach (int i_value in m_int_col) { if (i_value > selection) number += i_value; //again the type T cannot be used } } static int[] m_int_col = { 0, -1, -3, 5, 7, -8 }; }

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  • How to configure a NSPopupButton for displaying multiple values in a TableView?

    - by jekmac
    Hi there! I'm using two entities A and B with to-many-to-many relationship. Lets say I got an entity A with attribute aAttrib and a to-many relationship aRelat to another entity B with attribute bAttrib and a to-many relationship bRelat with entity A. Now I am building an interface with two tables one for entity A and another for entity B. The table for entity B has two columns one for bAttrib and one for the relationship aRelat. The aRelat-column should be a NSPopupButtonCell to display multiple aAttrib values. I'd like to set all the bindings in InterfaceBuilder in Table Column Bindings: -- I have two NSArrayController each for one entity: Object Controller Mode:Entity Array Controller Bindings: Parameters Managed Object Context bind to File's Owner -- One Table Cloumn with a PopUpButtonCell: TableCloumnBindings Content bind to Entity A with ControllerKey arrangedObjects; Content Values bind to Entity A with ModelKeyPath aAttrib Selected Object bind to Entity B with ModelKeyPath bRelat I know that this configuration doesn't allow multiple value setting. But I don't know how to do the right one. Getting the following message: HIToolbox: ignoring exception 'Unacceptable type of value for to-many relationship: property = "bRelat"; desired type = NSSet; given type = NSCFString; value = testValue.' that raised inside Carbon event dispatch... Does anyone have any idea?

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  • Updating Pointer using signals and slots

    - by Umesha MS
    Hi, I am very new to the QT; please help me to solve the problem. I am using thread to perform intensive operation in back ground. Meanwhile I want to update the UI, so I am using SIGNALS and SLOTS. To update UI I emit a signal and update UI. Let us consider bellow sample code, struct sample { QString name; QString address; }; void Update(sample *); void sampleFunction() { sample a; a.name = "Sachin Tendulkar"; a.address = "India" emit Update(&a); } In the above code we are creating a local object and passing the address of local object. In the QT document, it says that when we emit a signal it will be placed in the queue and late it will be delivered to the windows. Since my object is in local scope it will be delete once it goes out of the scope. Please tell me a way to send a pointer in a signal.

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  • View isn't scrolling back down after I dismiss the keyboard

    - by fmi
    I have a Tab Bar app. One of the views has a UITextView that is hidden by the keyboard when touched. I've set the view to scroll to account for the keyboard but it the view doesn't always return to it's original position after I dismiss the keyboard. Here is my code: //Scroll the view for keyboard - (void)viewWillAppear:(BOOL)animated { void (^keyBoardWillShow) (NSNotification *)= ^(NSNotification * notif) { NSDictionary* info = [notif userInfo]; NSValue* aValue = [info objectForKey:UIKeyboardFrameEndUserInfoKey]; CGSize keyboardSize = [aValue CGRectValue].size; float bottomPoint = (additionalView.frame.origin.y + additionalView.frame.size.height + 10); scrollAmount = keyboardSize.height - (self.view.frame.size.height - bottomPoint); if (scrollAmount > 0) { moveViewUp =YES; [self scrollTheView:YES]; } else moveViewUp = NO; }; [[NSNotificationCenter defaultCenter] addObserverForName:UIKeyboardWillShowNotification object:self.view.window queue:nil usingBlock:keyBoardWillShow]; void (^keyBoardWillHide) (NSNotification *)= ^(NSNotification * notif) { if (moveViewUp) [self scrollTheView:NO]; }; [[NSNotificationCenter defaultCenter] addObserverForName:UIKeyboardWillHideNotification object:self.view.window queue:nil usingBlock:keyBoardWillHide]; [super viewWillAppear:animated]; } - (void)viewWillDisappear:(BOOL)animated { [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil]; [super viewWillDisappear:animated]; } (void)scrollTheView:(BOOL)movedUp { [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:0.3]; CGRect rect = self.view.frame; if (movedUp){ rect.origin.y -= scrollAmount; } else { rect.origin.y += scrollAmount; } self.view.frame = rect; [UIView commitAnimations]; }

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  • Enum.TryParse with Flags attribute

    - by Sunny
    I have written code to TryParse enum either by value or by its name as shown below. How can I extend this code to include parsing enums with Flags attribute? public static bool TryParse<T>(this T enum_type, object value, out T result) where T : struct { return enum_type.TryParse<T>(value, true, out result); } public static bool TryParse<T>(this T enum_type, object value, bool ignoreCase, out T result) where T : struct { result = default(T); var is_converted = false; var is_valid_value_for_conversion = new Func<T, object, bool, bool>[]{ (e, v, i) => e.GetType().IsEnum, (e, v, i) => value != null, (e, v, i) => Enum.GetNames(e.GetType()).Any(n => String.Compare(n, v.ToString(), i) == 0) || Enum.IsDefined(e.GetType(), v) }; if(is_valid_value_for_conversion.All(rule => rule(enum_type, value, ignoreCase))){ result = (T)Enum.Parse(typeof(T), value.ToString(), ignoreCase); is_converted = true; } return is_converted; } Currently this code works for the following enums: enum SomeEnum{ A, B, C } // can parse either by 'A' or 'a' enum SomeEnum1 : int { A = 1, B = 2, C = 3 } // can parse either by 'A' or 'a' or 1 or "1" Does not work for: [Flags] enum SomeEnum2 { A = 1, B = 2, C = 4 } // can parse either by 'A' or 'a' // cannot parse for A|B Thanks!

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  • Mysterious HttpSession and session-config dependency

    - by OneMoreVladimir
    Good day. I'm developing a Java web app with Servlets\JSP using Tomcat 7.0. During request from client I put and object into the session and use forward. After the forward processing the same request the object can be retreived if the secure parameter is false otherwise it is not stored in session. <session-config> <session-timeout>15</session-timeout> <cookie-config> <http-only>true</http-only> <secure>true</secure> </cookie-config> <tracking-mode>COOKIE</tracking-mode> </session-config> I've figured out that "...cookies can be created with the 'secure' flag, which ensures that the browser will never transmit the specified cookie over non-SSL...". I've configured Tomcat to use SSL, but that haven't helped. Changing the tracking mode to SSL haven't helped as well. How do session-config and HttpSession object correlate in this case? What could be the problem?

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  • How to: StructureMap and configuration based on runtime parameters?

    - by user981375
    In a nutshell - I want to be able to instantiate object based on runtime parameters. In this particular case there are only two parameters but the problem is that I'm facing different permutations of these parameters and it gets messy. Here is the situation: I want to get an instance of an object specific to, say, given country and then, say, specific state/province. So, considering the US, there are 50 possible combinations. In reality it's less than that but that's the max. Think of it this way, I want to find out what's the penalty for smoking pot in a given country/state, I pass this information in and I get instantiated object telling me what it is. To the code (for reference only): interface IState { string Penalty { get; } } interface ICountry { IState State { get; set; } string Name { get; } } class BasePenalty : IState { virtual public string Penalty { get { return "Slap on a wrist"; } } } class USA : ICountry { public USA(IState state) { State = state; } public IState State { get; set; } public string Name { get { return "USA"; } } } class Florida: BasePenalty { public override string Penalty { get { return "Public beheading"; } } } // and so on ... I defined other states // which have penalties other than the "Slap on a wrist" How do I configure my container that when given country and state combination it will return the penalty? I tried combinations of profile and contextual binding but that configuration was directly proportional to the number of classes I've created. I have already gone thru trouble of defining different combinations. I'd like to avoid having to do the same during container configuration. I want to inject State into the Country. Also, I'd like to return UsaBasePenalty value in case state is not specified. Is that possible? Perhaps these is something wrong with the design.

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  • Why ng-hide don't work with custom directives?

    - by javier
    I'm reading the directives section of the developers guide on angularjs.org to refresh my knowledge and gain some insights and I was trying to run one of the examples but the directive ng-hide is not working on a custom directive. Here the jsfiddle: http://jsfiddle.net/D3Nsk/: <my-dialog ng-hide="dialogIsHidden" on-close="hideDialog()"> Does Not Work Here!!! </my-dialog> <div ng-hide="dialogIsHidden"> It works Here. </div> Any idea on why this is happening? Thanks. solution Seems that the variable dialogIsHidden on the tag already make a reference to a scope variable inside the directive and not to the variable in the controller; given that the directive has it's own insolated scope, to make this work it's necesary to pass by reference the variable dialogIsHidden of the controller to the directive. Here the jsfiddle: http://jsfiddle.net/h7xvA/ changes at: <my-dialog ng-hide="dialogIsHidden" on-close="hideDialog()" dialog-is-hidden='dialogIsHidden'> and: scope: { 'close': '&onClose', 'dialogIsHidden': '=' },

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  • Updating a composite primary key

    - by VBCSharp
    I am struggling with the philosophical discussions about whether or not to use composite primary keys on my SQL Server database. I have always used the surrogate keys in the past and I am challenging myself by leaving my comfort zone to try something different. I have read many discussion but can't come to any kind of solution yet. The struggle I am having is when I have to update a record with the composite PK. For example, the record in questions is like this: ContactID, RoleID, EffectiveDate, TerminationDT. The PK in this case is the ContactID, RoleID, and EffectiveDate. TerminationDT can be null. If in my UI, the user changes the RoleID and then I need to update the record. Using the surrogate key I can do an Update Table Set RoleID = 1 WHERE surrogateID = Z. However, using the Composite Key way, once one of the fields in the composite key changes I have no way to reference the old record to update it without now maintaining somewhere in the UI a reference to the old values. I do not bind datasources in my UI. I open a connection, get the data and store it in a bucket, then close the connection. What are everyone's opinions? Thanks.

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  • powershell missing member methods in array

    - by Andrew
    Hi Guys I have (yet another) powershell query. I have an array in powershell which i need to use the remove() and split commands on. Normally you set an array (or variable) and the above methods exist. On the below $csv2 array both methods are missing, i have checked using the get-member cmd. How can i go about using remove to get rid of lines with nan. Also how do i split the columns into two different variables. at the moment each element of the array displays one line, for each line i need to convert it into two variables, one for each column. timestamp Utilization --------- ----------- 1276505880 2.0763250000e+00 1276505890 1.7487730000e+00 1276505900 1.6906890000e+00 1276505910 1.7972880000e+00 1276505920 1.8141900000e+00 1276505930 nan 1276505940 nan 1276505950 0.0000000000e+00 $SystemStats = (Get-F5.iControl).SystemStatistics $report = "c:\snmp\data" + $gObj + ".csv" ### Allocate a new Query Object and add the inputs needed $Query = New-Object -TypeName iControl.SystemStatisticsPerformanceStatisticQuery $Query.object_name = $i $Query.start_time = $startTime $Query.end_time = 0 $Query.interval = $interval $Query.maximum_rows = 0 ### Make method call passing in an array of size one with the specified query $ReportData = $SystemStats.get_performance_graph_csv_statistics( (,$Query) ) ### Allocate a new encoder and turn the byte array into a string $ASCII = New-Object -TypeName System.Text.ASCIIEncoding $csvdata = $ASCII.GetString($ReportData[0].statistic_data) $csv2 = convertFrom-CSV $csvdata $csv2

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  • TreeView Control Problem

    - by ProgNet
    Hi all, I have a public folder on the server that contains recursively nested sub folders. In the various Leaf folders contains Images. I wanted to create a server side file browser that will display the Images to the user. I am using the ASP.NET TreeView Control. I create the tree nodes using PopulateOnDemand. If the user click on a leaf directory I want the images in that folder to be displayed in a DataList Control. The problem is that when I click on a sub tree node (after I expanded it parent node) All the expanded sub tree disappears and only the parent node is showed with no + sign next to it !! ( I have set the TreeView's PopulateNodesFromClient property to true ) Can someone tell me what is the problem ?? Thanks Here is the code : <asp:TreeView ID="TreeView1" runat="server" AutoGenerateDataBindings="False" onselectednodechanged="TreeView1_SelectedNodeChanged" ontreenodepopulate="TreeView1_TreeNodePopulate"> </asp:TreeView> protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { string path = Server.MapPath("."); PopulateTopNodes(path); } } private void PopulateTopNodes(string pathToRootFolder) { DirectoryInfo dirInfo = new DirectoryInfo(pathToRootFolder); DirectoryInfo[] dirs = dirInfo.GetDirectories(); foreach (DirectoryInfo dir in dirs) { TreeNode folderNode = new TreeNode(dir.Name,dir.FullName); if (dir.GetDirectories().Length > 0) { folderNode.PopulateOnDemand = true; folderNode.Collapse(); } TreeView1.Nodes.Add(folderNode); } } protected void TreeView1_TreeNodePopulate(object sender, TreeNodeEventArgs e) { if (IsCallback == true) { if (e.Node.ChildNodes.Count == 0) { LoadChildNode(e.Node); } } } private void LoadChildNode(TreeNode treeNode) { DirectoryInfo dirInfo = new DirectoryInfo(treeNode.Value); DirectoryInfo[] dirs = dirInfo.GetDirectories(); foreach (DirectoryInfo dir in dirs) { TreeNode folderNode = new TreeNode(dir.Name, dir.FullName); if(dir.GetDirectories().Length>0){ folderNode.PopulateOnDemand = true; folderNode.Collapse(); } treeNode.ChildNodes.Add(folderNode); } } protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e) { // Retrieve the images here }

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  • Large Switch statements: Bad OOP?

    - by Mystere Man
    I've always been of the opinion that large switch statements are a symptom of bad OOP design. In the past, I've read articles that discuss this topic and they have provided altnerative OOP based approaches, typically based on polymorphism to instantiate the right object to handle the case. I'm now in a situation that has a monsterous switch statement based on a stream of data from a TCP socket in which the protocol consists of basically newline terminated command, followed by lines of data, followed by an end marker. The command can be one of 100 different commands, so I'd like to find a way to reduce this monster switch statement to something more manageable. I've done some googling to find the solutions I recall, but sadly, Google has become a wasteland of irrelevant results for many kinds of queries these days. Are there any patterns for this sort of problem? Any suggestions on possible implementations? One thought I had was to use a dictionary lookup, matching the command text to the object type to instantiate. This has the nice advantage of merely creating a new object and inserting a new command/type in the table for any new commands. However, this also has the problem of type explosion. I now need 100 new classes, plus I have to find a way to interface them cleanly to the data model. Is the "one true switch statement" really the way to go? I'd appreciate your thoughts, opinions, or comments.

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  • Is there a case for parameterising using Abstract classes rather than Interfaces?

    - by Chris
    I'm currently developing a component based API that is heavily stateful. The top level components implement around a dozen interfaces each. The stock top-level components therefore sit ontop of a stack of Abstract implementations which in turn contain multiple mixin implementations and implement multiple mixin interfaces. So far, so good (I hope). The problem is that the base functionality is extremely complex to implement (1,000s of lines in 5 layers of base classes) and therefore I do not wish for component writers to implement the interfaces themselves but rather to extend my base classes (where all the boiler plate code is already written). If the API therefore accepts interfaces rather than references to the Abstract implementation that I wish for component writers to extends, then I have a risk that the implementer will not perform the validation that is both required and assumed by other areas of code. Therefore, my question is, is it sometimes valid to paramerise API methods using an abstract implementation reference rather than a reference to the interface(s) that it implements? Do you have an example of a well-designed API that uses this technique or am I trying to talk myself into bad-practice?

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  • Laravel4: Checking many-to-many relationship attribute even when it does not exist

    - by Simo A.
    This is my first time with Laravel and also Stackoverflow... I am developing a simple course management system. The main objects are User and Course, with a many-to-many relationship between them. The pivot table has an additional attribute, participant_role, which defines whether the user is a student or an instructor within that particular course. class Course extends Eloquent { public function users() { return $this->belongsToMany('User')->withPivot('participant_role')->withTimestamps(); } } However, there is an additional role, system admin, which can be defined on the User object. And this brings me mucho headache. In my blade view I have the following: @if ($course->pivot->participant_role == 'instructor') { // do something here... } This works fine when the user has been assigned to that particular $course and there is an entry for this user-course combination in the pivot table. However, the problem is the system administrator, who also should be able to access course details. The if-clause above gives Trying to get property of non-object error, apparently because there is no entry in the pivot table for system administrator (as the role is defined within the User object). I could probably solve the problem by using some off-the-shelf bundle for handling role-based permissions. Or I could (but don't want to) do something like this with two internal if-clauses: if (!empty($course->pivot)) { if ($course->pivot->participant_role == 'instructor') { // do something... } } Other options (suggested in partially similar entries in Stackoverflow) would include 1) reading all the pivot table entries to an array, and use in_array to check if a role exists, or even 2) SQL left join to do this on database level. However, ultimately I am looking for a compact one-line solution? Can I do anything similar to this, which unfortunately does not seem to work? if (! empty ($course->pivot->participant_role == 'instructor') ) { // do something... } The shorter the answer, the better :-). Thanks a lot!

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  • Another php array looping question

    - by Dan
    Been battling with this one for what seems, like forever. I have an array: $url_array It contains this info: Array ( [ppp] => Array ( [0] => stdClass Object ( [id] => 46660 [entity_id] => 0 [redirect_url] => http://www.google.com [type] => Image ) [1] => stdClass Object ( [id] => 52662 [entity_id] => 0 [pixel_redirect_url] => http://www.yahoo.com [type] => Image ) [2] => stdClass Object ( [id] => 53877 [entity_id] => 0 [redirect_url] => http://www.msn.com [pixel_type] => Image ) ) [total_count] => 3 ) I need to loop through it, and do things to each variable. I can get this to work: foreach ($piggies_array as $key => $value) { $id = $value[0]->id; $redirect_url = $value[0]->redirect_url; } Not unsurprisingly, it's only echoing the first value of those variables, but no matter what I try I cannot get it to loop through: $value->redirect_url; $value=>redirect_url; I would appreciate any help.

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  • Changing pointer of self

    - by rob5408
    I have an object that I alloc/init like normal just to get a instance. Later in my application I want to load state from disk for that object. I figure I could unarchive my class (which conforms to NSCoding) and just swap where my instance points to. To this end I use this code... NSString* pathForDataFile = [self pathForDataFile]; if([[NSFileManager defaultManager] fileExistsAtPath:pathForDataFile] == YES) { NSLog(@"Save file exists"); NSData *data = [[NSMutableData alloc] initWithContentsOfFile:pathForDataFile]; NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data]; [data release]; Person *tempPerson = [unarchiver decodeObjectForKey:@"Person"]; [unarchiver finishDecoding]; [unarchiver release]; if (tempPerson) { [self release]; self = [tempPerson retain]; } } Now when I sprinkled some NSLogs throughout my application I noticed self.person: <Person: 0x3d01a10> (After I create the object with alloc/init) self: <Person: 0x3d01a10> (At the start of this method) tempPerson: <Person: 0x3b1b880> (When I create the tempPerson) self: <Person: 0x3b1b880> (after i point self to the location of the tempPerson) self.person: <Person: 0x3d01a10> (After the method back in the main program) What am I missing?

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  • What techniques can I employ to create a series of UI Elements from a collection of objects using WP

    - by elggarc
    I'm new to WPF and before I dive in solving a problem in completely the wrong way I was wondering if WPF is clever enough to handle something for me. Imagine I have a collection containing objects. Each object is of the same known type and has two parameters. Name (a string) and Picked (a boolean). The collection will be populated at run time. I would like to build up a UI element at run time that will represent this collection as a series of checkboxes. I want the Picked parameter of any given object in the collection updated if the user changes the selected state of the checkbox. To me, the answer is simple. I iterate accross the collection and create a new checkbox for each object, dynamically wiring up a ValueChanged event to capture when Picked should be changed. It has occured to me, however, that I may be able to harness some unknown feature of WPF to do this better (or "properly"). For example, could data binding be employed here? I would be very interested in anyone's thoughts. Thanks, E FootNote: The structure of the collection can be changed completely to better fit any chosen solution but ultimately I will always start from, and end with, some list of string and boolean pairs.

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  • ASP.net MVC Linq-To-SQL Extended Class Field Binding

    - by user336858
    Hi there, The short version of this question is "Is there a way to get automatic View Object binding for fields defined in a partial class for a Linq-To-SQL generated class?" Apologies if it's been asked before. Example Suppose I have a typical MVC setup with the tables: Posts {PostID, ...} Categories {CategoryID, ...} A post can have more than one category, and a category can identify more than one post. Thus suppose further that I need an extra table: PostCategories {PostID, CategoryID, ...} This handles the many-to-many relationship between posts and categories. As far as I know, there's no way to do this in Linq-to-SQL right now so I have to shoehorn it in by adding a partial Postclass to the project to add that functionality. Something like: public partial class Post { public IEnumerable<Category> Categories{ get { ... } set { ... } } } So here's my question: If a user is accessing my MVC application front-end and begins editing a Post object, they might enter an invalid category. When the server recognizes the invalid input, the usual practice is to return the faulty object to the original view for re-editing along with some error messages. The fields in the edit page are re-populated with the provided values. However I don't know how to get this mechanism to work with the properties I created with the partial class as shown above. Any terminology, links, or tips you can provide would be tremendously helpful!

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  • Concurrent connections in C# socket

    - by Chu Mai
    There are three apps run at the same time, 2 clients and 1 server. The whole system should function as following: The client sends an serialized object to server then server receives that object as a stream, finally the another client get that stream from server and deserialize it. This is the sender: TcpClient tcpClient = new TcpClient(); tcpClient.Connect("127.0.0.1", 8888); Stream stream = tcpClient.GetStream(); BinaryFormatter binaryFormatter = new BinaryFormatter(); binaryFormatter.Serialize(stream, event); // Event is the sending object tcpClient.Close(); Server code: TcpListener listener = new TcpListener(IPAddress.Parse("127.0.0.1"), 8888); listener.Start(); Console.WriteLine("Server is running at localhost port 8888 "); while (true) { Socket socket = listener.AcceptSocket(); try { Stream stream = new NetworkStream(socket); // Typically there should be something to write the stream // But I don't knwo exactly what should the stream write } catch (Exception e) { Console.WriteLine("Exception: " + e.Message); Console.WriteLine("Disconnected: {0}", socket.RemoteEndPoint); } } The receiver: TcpClient client = new TcpClient(); // Connect the client to the localhost with port 8888 client.Connect("127.0.0.1", 8888); Stream stream = client.GetStream(); Console.WriteLine(stream); when I run only the sender and server, and check the server, server receives correctly the data. The problem is when I run the receiver, everything is just disconnected. So where is my problem ? Could anyone point me out ? Thanks

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  • How to split this string and identify first sentence after last '*'?

    - by DaveDev
    I have to get a quick demo for a client, so this is a bit hacky. Please don't flame me too much! :-) I'm getting a string similar to the following back from the database: The object of the following is to do: * blah 1 * blah 2 * blah 3 * blah 4. Some more extremely uninteresting text. Followed by yet another sentence full of extrememly uninteresting text. Thankfully this is the last sentence. I need to format this so that each * represents a bullet point, and the sentence after the last * goes onto a new line, ideally as follows: The object of the following is to do: blah 1 (StackOverflow wants to add bullet points here, but I just need '*') blah 2 blah 3 blah 4. Some more extremely uninteresting text. Followed by yet another sentence full of extrememly uninteresting text. Thankfully this is the last sentence. It's easy enough to split the string by the * character and replace that with <br /> *. I'm using the following for that: string description = GetDescription(); description = description.Replace("*", "<br />*"); // it's going onto a web page. but the result this gives me is: The object of the following is to do: blah 1 blah 2 blah 3 blah 4. Some more extremely uninteresting text. Followed by yet another sentence full of extrememly uninteresting text. Thankfully this is the last sentence. I'm having a bit of difficulty identifying the fist sentence after the last '*' so I can put a break there too. Can somebody show me how to do this?

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