Search Results

Search found 29508 results on 1181 pages for 'object initializers'.

Page 571/1181 | < Previous Page | 567 568 569 570 571 572 573 574 575 576 577 578  | Next Page >

  • Message Handlers and the WeakReference issue

    - by user1058647
    The following message Handler works fine receiving messages from my service... private Handler handler = new Handler() { public void handleMessage(Message message) { Object path = message.obj; if (message.arg1 == 5 && path != null) //5 means its a single mapleg to plot on the map { String myString = (String) message.obj; Gson gson = new Gson(); MapPlot mapleg = gson.fromJson(myString, MapPlot.class); myMapView.getOverlays().add(new DirectionPathOverlay(mapleg.fromPoint, mapleg.toPoint)); mc.animateTo(mapleg.toPoint); } else { if (message.arg1 == RESULT_OK && path != null) { Toast.makeText(PSActivity.this, "Service Started" + path.toString(), Toast.LENGTH_LONG).show(); } else { Toast.makeText(PSActivity.this,"Service error" + String.valueOf(message.arg1), Toast.LENGTH_LONG).show(); } } }; }; However, even though it tests out alright in the AVD (I'm feeding it a large KML file via DDMS) the "object path = message.obj;" line has a WARNING saying "this Handler class should be static else leaks might occur". But if I say "static Handler handler = new Handler()" it won't compile complaining that I "cannot make a static reference to a non-static field myMapView. If I can't make such references, I can't do anything useful. This led me into several hours of googling around on this issue and learning more about weakReferences than I ever wanted to know. The often found reccomendation I find is that I should replace... private Handler handler = new Handler() with static class handler extends Handler { private final WeakReference<PSActivity> mTarget; handler(PSActivity target) { mTarget = new WeakReference<PSActivity>(target); } But this won't compile still complaining that I can't make a static reference to a non-dtatic field. So, my question a week or to ago was "how can I write a message handler for android so my service can send data to my activity. Even though I have working code, the question still stands with the suffix "without leaking memory". Thanks, Gary

    Read the article

  • SQLAlchemy, one to many vs many to one

    - by sadvaw
    Dear Everyone, I have the following data: CREATE TABLE `groups` ( `bookID` INT NOT NULL, `groupID` INT NOT NULL, PRIMARY KEY(`bookID`), KEY( `groupID`) ); and a book table which basically has books( bookID, name, ... ), but WITHOUT groupID. There is no way for me to determine what the groupID is at the time of the insert for books. I want to do this in sqlalchemy. Hence I tried mapping Book to the books joined with groups on book.bookID=groups.bookID. I made the following: tb_groups = Table( 'groups', metadata, Column('bookID', Integer, ForeignKey('books.bookID'), primary_key=True ), Column('groupID', Integer), ) tb_books = Table( 'books', metadata, Column('bookID', Integer, primary_key=True), tb_joinedBookGroup = sql.join( tb_books, tb_groups, \ tb_books.c.bookID == tb_groups.c.bookID) and defined the following mapper: mapper( Group, tb_groups, properties={ 'books': relation(Book, backref='group') }) mapper( Book, tb_joinedBookGroup ) ... However, when I execute this piece of code, I realized that each book object has a field groups, which is a list, and each group object has books field which is a singular assigment. I think my definition here must have been causing sqlalchemy to be confused about the many-to-one vs one-to-many relationship. Can someone help me sort this out? My desired goal is g.books = [b, b, b, .. ] book.group = g, where g is an instance of group, and b is an instance of book

    Read the article

  • Entity Framework POCO objects

    - by Dan
    I'm struggling with understanding Entity Framework and POCO objects. Here's what I'm trying to achieve. 1) Separate the DAL from the Business Layer by having my business layer use an interface to my DAL. Maybe use Unity to create my context. 2) Use Entity Framework inside my DAL. I have a Domain model with objects that reside in my business layer. I also have a database full of tables that doesn't really represent my domain model. I setup Entity Framework and generated POCO objects by using the ADO.NET POCO Generator extension. This gave me an object for each table in my database. Now I want to be able to say context.GetAll<User>(); and have it return a list of my User objects. The User object is in my business layer. Is that possible? Does that make sense or am I totally off and should start over? I'm guessing I need to use the repository pattern to achieve this, but I'm not sure. Can anyone help?

    Read the article

  • GUID or int entity key with SQL Compact/EF4?

    - by David Veeneman
    This is a follow-up to an earlier question I posted on EF4 entity keys with SQL Compact. SQL Compact doesn't allow server-generated identity keys, so I am left with creating my own keys as objects are added to the ObjectContext. My first choice would be an integer key, and the previous answer linked to a blog post that shows an extension method that uses the Max operator with a selector expression to find the next available key: public static TResult NextId<TSource, TResult>(this ObjectSet<TSource> table, Expression<Func<TSource, TResult>> selector) where TSource : class { TResult lastId = table.Any() ? table.Max(selector) : default(TResult); if (lastId is int) { lastId = (TResult)(object)(((int)(object)lastId) + 1); } return lastId; } Here's my take on the extension method: It will work fine if the ObjectContext that I am working with has an unfiltered entity set. In that case, the ObjectContext will contain all rows from the data table, and I will get an accurate result. But if the entity set is the result of a query filter, the method will return the last entity key in the filtered entity set, which will not necessarily be the last key in the data table. So I think the extension method won't really work. At this point, the obvious solution seems to be to simply use a GUID as the entity key. That way, I only need to call Guid.NewGuid() method to set the ID property before I add a new entity to my ObjectContext. Here is my question: Is there a simple way of getting the last primary key in the data store from EF4 (without having to create a second ObjectContext for that purpose)? Any other reason not to take the easy way out and simply use a GUID? Thanks for your help.

    Read the article

  • Pass an array from IronRuby to C#

    - by cgyDeveloper
    I'm sure this is an easy fix and I just can't find it, but here goes: I have a C# class (let's call it Test) in an assembly (let's say SOTest.dll). Here is something along the lines of what I'm doing: private List<string> items; public List<string> list_items() { return this.items; } public void set_items(List<string> new_items) { this.items = new_items; } In the IronRuby interpreter I run: >>> require "SOTest.dll" true >>> include TestNamespace Object >>> myClass = Test.new TestNamespace.Test >>> myClass.list_items() ['Apples', 'Oranges', 'Pears'] >>> myClass.set_items ['Peaches', 'Plums'] TypeError: can't convert Array into System::Collections::Generic::List(string) I get a similar error whether I make the argument a 'List< string ', 'List< object ' or 'string[ ]'. What is the proper syntax? I can't find a documented mapping of types anywhere (because it's likely too complicated to define in certain scenarios given what Ruby can do).

    Read the article

  • Weird compile-time behavior when trying to use primitive type in generics

    - by polygenelubricants
    import java.lang.reflect.Array; public class PrimitiveArrayGeneric { static <T> T[] genericArrayNewInstance(Class<T> componentType) { return (T[]) Array.newInstance(componentType, 0); } public static void main(String args[]) { int[] intArray; Integer[] integerArray; intArray = (int[]) Array.newInstance(int.class, 0); // Okay! integerArray = genericArrayNewInstance(Integer.class); // Okay! intArray = genericArrayNewInstance(int.class); // Compile time error: // cannot convert from Integer[] to int[] integerArray = genericArrayNewInstance(int.class); // Run time error: // ClassCastException: [I cannot be cast to [Ljava.lang.Object; } } I'm trying to fully understand how generics works in Java. Things get a bit weird for me in the 3rd assignment in the above snippet: the compiler is complaining that Integer[] cannot be converted to int[]. The statement is 100% true, of course, but I'm wondering WHY the compiler is making this complaint. If you comment that line, and follow the compiler's "suggestion" as in the 4th assignment, the compiler is actually satisfied!!! NOW the code compiles just fine! Which is crazy, of course, since like the run time behavior suggests, int[] cannot be converted to Object[] (which is what T[] is type-erased into at run time). So my question is: why is the compiler "suggesting" that I assign to Integer[] instead for the 3rd assignment? How does the compiler reason to arrive to that (erroneous!) conclusion?

    Read the article

  • Where are the network boundaries in the Java Connector Architecture (JCA)?

    - by Laird Nelson
    I am writing a JCA resource adapter. I'm also, as I go, trying to fully understand the connection management portion of the JCA specification. As a thought experiment, pretend that the only client of this adapter will be a Swing Java Application Client located on a different machine. Also assume that the resource adapter will communicate with its "enterprise information system" (EIS) over the network as well. As I understand the JCA specification, the .rar file is deployed to the application server. The application server creates the .rar file's implementation of the ManagedConnectionFactory interface. It then asks it to produce a connection factory, which is the opaque object that is deployed to JNDI for the user to use to obtain a connection to the resource. (In the case of JDBC, the connection factory is a javax.sql.DataSource.) It is a requirement that the connection factory retain a reference to the application-server-supplied ConnectionManager, which, in turn, is required to be Serializable. This makes sense--in order for the connection factory to be stored in JNDI, it must be serializable, and in order for it to keep a reference to the ConnectionManager, the ConnectionManager must also be serializable. So fine, this little object graph gets installed in the application client's JNDI tree. This is where I start to get queasy. Is the ConnectionManager--the piece supplied by the application server that is supposed to handle connection management, sharing, pooling, etc.--wholly present on the client at this point? One of its jobs is to create ManagedConnection instances, and a ManagedConnection is not required to be Serializable, and the user connection handles it vends are also not required to be Serializable. That suggests to me that the whole connection pooling machinery is shipped wholesale to the application client and stuffed into its JNDI tree. Does this all mean that JCA interactions from the client side bypass the server-side componentry of the application server? Where are the network boundaries in the JCA API?

    Read the article

  • wpf treeview does not show child objects

    - by gangt
    I have an object with child object(s) and I load it using linq. And I assign it to a treeView's itemssource. treeView.DisplayMemberPath = "Name"; treeView.ItemsSource = tasks; It shows only the parent nodes (task.name), I couldn't figure out how to add children (TaskItems.name). All the examples show HierarchicalData in xaml. I need to do it in code-behind, just like the above code. Is it possible? public class Task { public int Id; public string Name; public bool IsActive; public List<TaskItem> TaskItems = new List<TaskItem>(); } public class TaskItem { public int TaskId; public string Name; public string Value; } -------------- var tasks1 = from t in xd.Descendants("taskheader") select new Task { Id = (int)t.Element("id"), Name = t.Element("name").Value, IsActive = t.Element("isactive").Value == "1", TaskItems = t.Elements("taskdetail").Select(e => new TaskItem { TaskId = (int)e.Element("taskid"), Name = (string)e.Element("name"), Value = (string)e.Element("value"), }).ToList() }; -------------- List<Task> tasks = new List<Task>(); tasks = tasks1;

    Read the article

  • HTML Helper/Text Box validation

    - by slandau
    I have this input on the view: <%= Html.TextBoxCurrentDateWithoutPermission("EffectiveDate", Model.EffectiveDate.HasValue ? Model.EffectiveDate.Value.ToString("dd-MMM-yyyy") : "", new string[] { PERMISSIONS.hasICAdvanced }, new { @class = "economicTextBox", propertyName = "EffectiveDate", onchange = "parseAndSetDt(this); ", dataType = "Date" })%> Here is the custom HTML Helper: public static MvcHtmlString TextBoxCurrentDateWithoutPermission( this HtmlHelper htmlHelper, string name, object value, string[] permissions, object htmlAttributes ) { foreach (string permission in permissions) { if (Chatham.Web.UI.Extranet.SessionManager.DisplayUser.IsInRole(permission)) { // the user has the permission => render the textbox return htmlHelper.TextBox(name, value, htmlAttributes); } } // the user has no permission => render a readonly checkbox var mergedHtmlAttributes = new RouteValueDictionary(htmlAttributes); mergedHtmlAttributes["disabled"] = "disabled"; return htmlHelper.TextBox(name, value == "" ? DateTime.Now : value, mergedHtmlAttributes); } The way this works now is, when a user does NOT have the permission passed in, the box is disabled. The way it needs to be -- if the user does NOT have the permission passed in, it needs to be enabled, however the only dates it can accept are todays date AND dates in the future. So I need JQuery validation (or just plain JS), for this textbox on the page for the following case: If the textbox is enabled AND the user does not have the permission, allow the user to input the current date or future dates ONLY.

    Read the article

  • creating new instance fails PHP

    - by as3isolib
    I am relatively new to PHP and having some decent success however I am running into this issue: If I try to create a new instance of the class GenericEntryVO, I get a 500 error with little to no helpful error information. However, if I use a generic object as the result, I get no errors. I'd like to be able to cast this object as a GenericEntryVO as I am using AMFPHP to communicate serialize data with a Flex client. I've read a few different ways to create constructors in PHP but the typical 'public function Foo()' for a class Foo was recommended for PHP 5.4.4 //in my EntryService.php class public function getEntryByID($id) { $link = mysqli_connect("localhost", "root", "root", "BabyTrackingAppDB"); if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } $query = "SELECT * FROM Entries WHERE id = '$id' LIMIT 1"; if ($result = mysqli_query($link, $query)) { // $entry = new GenericEntryVO(); this is where the problem lies! while ($row = mysqli_fetch_row($result)) { $entry->id = $row[0]; $entry->entryType = $row[1]; $entry->title = $row[2]; $entry->description = $row[3]; $entry->value = $row[4]; $entry->created = $row[5]; $entry->updated = $row[6]; } } mysqli_free_result($result); mysqli_close($link); return $entry; } //my GenericEntryVO.php class <?php class GenericEntryVO { public function __construct() { } public $id; public $title; public $entryType; public $description; public $value; public $created; public $updated; // public $properties; } ?>

    Read the article

  • iBatis how to solve a more complex N+1 problem

    - by Alvin
    I have a database that is similar to the following: create table Store(storeId) create table Staff(storeId_fk, staff_id, staffName) create table Item(storeId_fk, itme_id, itemName) The Store table is large. And I have create the following java bean public class Store { List<Staff> myStaff List<Item> myItem .... } public class Staff { ... } public class Item { ... } My question is how can I use iBatis's result map to EFFICIENTLY map from the tables to the java object? I tried: <resultMap id="storemap" class="my.example.Store"> <result property="myStaff" resultMap="staffMap"/> <result property="myItem" result="itemMap"/> </resultMap> (other maps omitted) But it's way too slow since the Store table is VERY VERY large. I tried to follow the example in Clinton's developer guide for the N+1 solution, but I cannot warp my mind around how to use the "groupBy" for an object with 2 list... Any help is appreciated!

    Read the article

  • Generic Class Vb.net

    - by KoolKabin
    hi guys, I am stuck with a problem about generic classes. I am confused how I call the constructor with parameters. My interface: Public Interface IDBObject Sub [Get](ByRef DataRow As DataRow) Property UIN() As Integer End Interface My Child Class: Public Class User Implements IDBObject Public Sub [Get](ByRef DataRow As System.Data.DataRow) Implements IDBObject.Get End Sub Public Property UIN() As Integer Implements IDBObject.UIN Get End Get Set(ByVal value As Integer) End Set End Property End Class My Next Class: Public Class Users Inherits DBLayer(Of User) #Region " Standard Methods " #End Region End Class My DBObject Class: Public Class DBLayer(Of DBObject As {New, IDBObject}) Public Shared Function GetData() As List(Of DBObject) Dim QueryString As String = "SELECT * ***;" Dim Dataset As DataSet = New DataSet() Dim DataList As List(Of DBObject) = New List(Of DBObject) Try Dataset = Query(QueryString) For Each DataRow As DataRow In Dataset.Tables(0).Rows **DataList.Add(New DBObject(DataRow))** Next Catch ex As Exception DataList = Nothing End Try Return DataList End Function End Class I get error in the starred area of the DBLayer Object. What might be the possible reason? what can I do to fix it? I even want to add New(byval someval as datatype) in IDBObject interface for overloading construction. but it also gives an error? how can i do it? Adding Sub New(ByVal DataRow As DataRow) in IDBObject producess following error 'Sub New' cannot be declared in an interface. Error Produced in DBLayer Object line: DataList.Add(New DBObject(DataRow)) Msg: Arguments cannot be passed to a 'New' used on a type parameter.

    Read the article

  • Is there any class in the .NET Framework to represent a holding container for objects?

    - by Charles Prakash Dasari
    I am looking for a class that defines a holding structure for an object. The value for this object could be set at a later time than when this container is created. It is useful to pass such a structure in lambdas or in callback functions etc. Say: class HoldObject<T> { public T Value { get; set; } public bool IsValueSet(); public void WaitUntilHasValue(); } // and then we could use it like so ... HoldObject<byte[]> downloadedBytes = new HoldObject<byte[]>(); DownloadBytes("http://www.stackoverflow.com", sender => downloadedBytes.Value = sender.GetBytes()); It is rather easy to define this structure, but I am trying to see if one is available in FCL. I also want this to be an efficient structure that has all needed features like thread safety, efficient waiting etc. Any help is greatly appreciated.

    Read the article

  • Nesting arbitrary objects in Java

    - by user1502381
    I am having trouble solving a particular problem in Java (which I did not find by search). I do not know how to create a nested lists of objects - with a different type of object/primitive type at the end. For example: *Note: only an example. I am actually doing this below with something other than Employee, but it serves as simple example. I have an array of an object Employee. It contains information on the Employee. public class Employee { int age int salary int yearsWorking public Employee () { // constructor... } // Accessors } What I need to do is organize the Employees by quantiles/percentiles. I have done so by the following: import org.apache.commons.math.stat.descriptive.rank.Percentile; public class EmployeeSort { public void main(String args[]) { Percentile p = new Percentile(); Employee[] employeeArray = new Employee(100); // filled employeeArray double[] ageArray new double[100]; // filled ageArray with ages from employeeArray int q = 25; // Percentile cutoff for (int i = 1; i*q < 100; i++) { // assign percentile cutoff to some array to contain the values } } } Now, the problem I have is that I need to organize the Employees first by the percentiles of age, then percentiles of yearsWorking, and finally by percentiles of salary. My Java knowledge is inadequate right now to solve this problem, but the project I was handed was in Java. I am primarily a python guy, so this problem would have been a lot easier in that language. No such luck.

    Read the article

  • Problem with generic list and extension method(C#3.0)

    - by Newbie
    I have an issue. I am making an extension class for a Collection and it is generic.. like public static class ListExtensions { public static ICollection<T> Search<T>(this ICollection<T> collection, string stringToSearch) { ICollection<T> t1=null; foreach (T t in collection) { Type k = t.GetType(); PropertyInfo pi = k.GetProperty("Name"); if (pi.GetValue(t,null).Equals(stringToSearch)) { t1.Add(t); } } return t1; } } But I cannot add items to t1 as it is declared null. Error: object reference not set to an instance of the object. I am calling the method like List<TestClass> listTC = new List<TestClass>(); listTC.Add(new TestClass { Name = "Ishu", Age = 21 }); listTC.Add(new TestClass { Name = "Vivek", Age = 40 }); listTC.Add(new TestClass { Name = "some one else", Age = 12 }); listTC.Search("Ishu"); And the test class is public class TestClass { public string Name { get; set; } public int Age { get; set; } } Using : (C#3.0) & Framework - 3.5 Thanks

    Read the article

  • Imlpementations of an Interface with Different Types?

    - by b3njamin
    Searched as best I could but unfortunately I've learned nothing relevant; basically I'm trying to work around the following problem in C#... For example, I have three possible references (refA, refB, refC) and I need to load the correct one depending on a configuration option. So far however I can't see a way of doing it that doesn't require me to use the name of said referenced object all through the code (the referenced objects are provided, I can't change them). Hope the following code makes more sense: public ??? LoadedClass; public Init() { /* load the object, according to which version we need... */ if (Config.Version == "refA") { Namespace.refA LoadedClass = new refA(); } else if (Config.Version == "refB") { Namespace.refB LoadedClass = new refB(); } else if (Config.Version == "refC") { Namespace.refC LoadedClass = new refC(); } Run(); } private void Run(){ { LoadedClass.SomeProperty... LoadedClass.SomeMethod(){ etc... } } As you can see, I need the Loaded class to be public, so in my limited way I'm trying to change the type 'dynamically' as I load in which real class I want. Each of refA, refB and refC will implement the same properties and methods but with different names. Again, this is what I'm working with, not by my design. All that said, I tried to get my head around Interfaces (which sound like they're what I'm after) but I'm looking at them and seeing strict types - which makes sense to me, even if it's not useful to me. Any and all ideas and opinions are welcome and I'll clarify anything if necessary. Excuse any silly mistakes I've made in the terminology, I'm learning all this for the first time. I'm really enjoying working with an OOP language so far though - coming from PHP this stuff is blowing my mind :-)

    Read the article

  • Hundreds of custom UserControls create thousands of USER Objects

    - by Andy Blackman
    I'm creating a dashboard application that shows hundreds of "items" on a FlowLayoutPanel. Each "item" is a UserControl that is made up of 12 or labels. My app queries a database and then creates an "item" instance for each record, populating ethe labels and textboxes with data before adding it to the FlowLayoutPanel. After adding about 560 items to the panel, I noticed that the USER Objects count in my Task Manager had gone up to about 7300, which was much much larger than any other app on my machine. I did a quick spot of mental arithmetic (OK, I might have used calc.exe) and figured that 560 * 13 (12 labels plus the UserControl itself) is 7280. So that suddenly gave away where all the objects were coming from... Knowing that there is a 10,000 USER object limit before windows throws in the towel, I'm trying to figure better ways of drawing these items onto the FlowLayoutPanel. My ideas so far are as follows: 1) User-draw the "item", using graphics.DrawText and DrawImage in place of many of the labels. I'm hoping that this will mean 1 item = 1 USER Object, not 13. 2) Have 1 instance of the "item", then for each record, populate the instance and use the Control.DrawToBitmap() method to grab an image and then use that in the FlowLayoutPanel (or similar) So... Does anyone have any other suggestions ??? P.S. It's a zoomable interface, so I have already ruled out "Paging" as there is a requirement to see all items at once :( Thanks everyone.

    Read the article

  • CoreData is saving model without the save: method being called

    - by chris
    I have a list of items with a plus button in the navigation bar that opens up a modal window containing a table of the models attributes, that displays a form when the table items are clicked (pretty standard form style). For some reason if I click the plus button to open the form to create a new model, then immediately click the done button, the person model is saved. The action linked to the done button does nothing but call on a delegate method notifying the personListViewController to close the window. The apple docs do state that the model is not saved after calling the insertNewObjectForEntityName: ... Simply creating a managed object does not cause it to be saved to a persistent store. The managed object context acts as a scratchpad. I am at a lost to why this is happening, but every time I click the done button I have a new blank item in the original tableView. I am using SDK v3.1.3 // PersonListViewController - open modal window - (void)addPerson { // Load the new form PersonNewViewController *newController = [[PersonNewViewController alloc] init]; newController.modalFormDelegate = self; [self presentModalViewController:newController animated:YES]; [newController release]; } // PersonFormViewController - (void)viewDidLoad { [super viewDidLoad]; if ( person == nil ) { MyAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate]; self.person = [NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:appDelegate.managedObjectContext]; } ... UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(done)]; self.navigationItem.rightBarButtonItem = doneButton; [doneButton release]; } - (IBAction) done { [self.modalFormDelegate didCancel]; } // delegate method in the original listViewController - (void) didCancel { [self dismissModalViewControllerAnimated:YES]; }

    Read the article

  • creating a QT gui using a thread in c++?

    - by rashid
    I am trying to create this QT gui using a thread but no luck. Below is my code. Problem is gui never shows up. But if i put QApplication app(m.s_argc,m.s_argv); //object instantiation guiClass *gui = new guiClass(); //show gui gui-show(); app.exec(); in main() then it works. /*INCLUDES HERE... .... */ using namespace std; struct mainStruct { int s_argc; char ** s_argv; }; typedef struct mainStruct mas; void *guifunc(void * arg); int main(int argc, char * argv[]) { mas m; m.s_argc = argc; m.s_argv = argv; pthread_t threadGUI; //start a new thread for gui int result = pthread_create(&threadGUI, NULL, guifunc, (void *) &m); if (result) { printf("Error creating gui thread"); exit(0); } return 0; } void *guifunc(void * arg) { mas m = *(mas *)arg; QApplication app(m.s_argc,m.s_argv); //object instantiation guiClass *gui = new guiClass(); //show gui gui-show(); app.exec(); }

    Read the article

  • VB.NET Two different approaches to generic cross-threaded operations; which is better?

    - by BASnappl
    VB.NET 2010, .NET 4 Hello, I recently read about using SynchronizationContext objects to control the execution thread for some code. I have been using a generic subroutine to handle (possibly) cross-thread calls for things like updating UI controls that utilizes Invoke. I'm an amateur and have a hard time understanding the pros and cons of any particular approach. I am looking for some insight on which approach might be preferable and why. Update: This question is motivated, in part, by statements such as the following from the MSDN page on Control.InvokeRequired. An even better solution is to use the SynchronizationContext returned by SynchronizationContext rather than a control for cross-thread marshaling. Method 1: Public Sub InvokeControl(Of T As Control)(ByVal Control As T, ByVal Action As Action(Of T)) If Control.InvokeRequired Then Control.Invoke(New Action(Of T, Action(Of T))(AddressOf InvokeControl), New Object() {Control, Action}) Else Action(Control) End If End Sub Method 2: Public Sub UIAction(Of T As Control)(ByVal Control As T, ByVal Action As Action(Of Control)) SyncContext.Send(New Threading.SendOrPostCallback(Sub() Action(Control)), Nothing) End Sub Where SyncContext is a Threading.SynchronizationContext object defined in the constructor of my UI form: Public Sub New() InitializeComponent() SyncContext = WindowsFormsSynchronizationContext.Current End Sub Then, if I wanted to update a control (e.g., Label1) on the UI form, I would do: InvokeControl(Label1, Sub(x) x.Text = "hello") or UIAction(Label1, Sub(x) x.Text = "hello") So, what do y'all think? Is one way preferred or does it depend on the context? If you have the time, verbosity would be appreciated! Thanks in advance, Brian

    Read the article

  • How to programmatically create a node in Drupal 8?

    - by chapka
    I'm designing a new module in Drupal 8. It's a long-term project that won't be going public for a few months at least, so I'm using it as a way to figure out what's new. In this module, I want to be able to programmatically create nodes. In Drupal 7, I would do this by creating the object, then calling "node_submit" and "node_save". These functions no longer exist in Drupal 8. Instead, according to the documentation, "Modules and scripts may programmatically submit nodes using the usual form API pattern." I'm at a loss. What does this mean? I've used Form API to create forms in Drupal 7, but I don't get what the docs are saying here. What I'm looking to do is programmatically create at least one and possibly multiple new nodes, based on information not taken directly from a user-presented form. I need to be able to: 1) Specify the content type 2) Specify the URL path 3) Set any other necessary variables that would previously have been handled by the now-obsolete node_object_prepare() 4) Commit the new node object I would prefer to be able to do this in an independent, highly abstracted function not tied to a specific block or form. So what am I missing?

    Read the article

  • TypeError when using v 0.8.1 of FLOT library, but no error with v. 0.7

    - by DanielAttard
    I need some help to figure out why I am getting an error when trying to create a simple graph using the jQuery FLOT library. When I reference version 0.7 of the FLOT library, the page renders correctly: http://attardpropertytax.ca/flot07.html But when I switch to version 0.8.1 of the FLOT library, the page returns an error saying: Uncaught TypeError: Cannot read property 'left' of null http://attardpropertytax.ca/flot81.html The HTML is the same for both pages, so I cannot figure out why the new version 0.8.1 of FLOT returns an error, but the old version 0.7 does not. Any ideas? I somehow stumbled across a work-around that managed to fix my problem. I'm nut sure why, but I had to comment-out the following two sections of code from the v. 0.8.1 FLOT library: This was the first spot: // If the grid is visible, add its border width to the offset for (var a in plotOffset) { if(typeof(options.grid.borderWidth) == "object") { plotOffset[a] += showGrid ? options.grid.borderWidth[a] : 0; } else { plotOffset[a] += showGrid ? options.grid.borderWidth : 0; } } And this was the second spot: if (isNaN(v) || v < axis.min || v > axis.max // skip those lying on the axes if we got a border || (t == "full" && ((typeof bw == "object" && bw[axis.position] > 0) || bw > 0) && (v == axis.min || v == axis.max))) continue; I'm sure eventually @DNS will be taking a look at this question and maybe he will be able to help me understand what is going wrong with my code. Thanks.

    Read the article

  • Delphi: Transporting Objects to remote computers

    - by pr0wl
    Hallo. I am writing a tier2 ordering software for network usage. So we have client and server. On the client I create Objects of TBest in which the Product ID, the amount and the user who orders it are saved. (So this is a item of an Order). An order can have multiple items and those are saved in an array to later send the created order to the server. The class that holds the array is called TBestellung. So i created both TBest.toString: string; and TBest.fromString(source: string): TBest; Now, I send the toString result to the server via socket and on the server I create the object using fromString (its parsing the attributes received). This works as intended. Question: Is there a better and more elegant way to do that? Serialisation is a keyword, yes, but isn't that awful / difficult when you serialize an object (TBestellung in this case) that contains an Array of other Objects (TBest in this case)? //Small amendment: Before it gets asked. Yes I should create an extra (static) class for toString and fromString because otherwise the server needs to create an "empty" TBest in order to be able to use fromString.

    Read the article

  • Webinvoke to POST JSON with ajax call

    - by G-Man
    This is my first time that I an using WCF Service with Knockout. I want to POST an entire view model as a JSON object with an ajax call. This is the error message that I get: Endpoints using 'UriTemplate' cannot be used with 'System.ServiceModel.Description.WebScriptEnablingBehavior' I have noticed that some developers send each value as a parameter which I feel is unnecessary especially if you work with a big object. This is my WCF method: [OperationContract] [WebInvoke(UriTemplate = "AddNewEvent?newEvent", Method = "POST", ResponseFormat = WebMessageFormat.Json, RequestFormat = WebMessageFormat.Json)] public bool AddNewEvent(Models.DAL_CRMEvents newEvent) { Entities.CRMEntities dbCRM = new Entities.CRMEntities(); //Models.CRMEvents crmEvent = new Models.CRMEvents(); Entities.Event crmEvent = new Entities.Event(); crmEvent.EventDateCreated = Convert.ToDateTime(newEvent.DateCreated); crmEvent.EventActive = true; crmEvent.EventDescription = newEvent.Description; crmEvent.EventDate = Convert.ToDateTime(newEvent.Date); crmEvent.EventTimeStart = TimeSpan.Parse(newEvent.TimeStart); crmEvent.EventTimeEnd = TimeSpan.Parse(newEvent.TimeEnd); crmEvent.EventAllDay = newEvent.AllDay; dbCRM.AddToEvent(crmEvent); return true; } This is my ajax function function SaveEvent (data) { var s = { newEvent: ko.mapping.toJS(data) } alert(data.AllDay()); $.ajax({ type: "POST", url: "../Services/CRMDataService.svc/AddNewEvent", data: JSON.stringify(s), contentType: "application/json; charset=utf-8", dataType: "JSON", success: function (result) { alert(result); }, error: function (jqXHR, textStatus, errorThrown) { if (textStatus == "error" && errorThrown != "") { var n = noty({ text: errorThrown, type: 'warning', dismissQueue: false, modal: true, layout: 'center', theme: 'defaults', callback: { } }) } } }) }

    Read the article

  • StackPanel loded is not getting fired in.cs page

    - by prince23
    <sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate> <StackPanel Loaded ="SPImage_Loaded" Orientation="Horizontal" Background="Transparent" > <Button x:Name="myButton" Click="Btn_Click"> <Image x:Name="imgMarks" " Stretch="None"/> </Button> </StackPanel> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> in .cs i have defined the event for stack panel private void SPImage_Loaded(object sender, RoutedEventArgs e) { try { var TargetMarks = sender as StackPanel; Image imgMarks= (Image)TargetScore.FindName("imgMarks"); Marks obj = (Marks )TargetMarks.DataContext; // here marks oject would be containg the details // here if marks.score object value is 1 then bind the image //else // dnt bind the image . that is logic i am trying to do. imgMarks.Source = new BitmapImage(new Uri("/Images/a1.png", UriKind.Relative)); } catch (Exception) { throw; } } any solution on this would be great. is there any better solution to achive this. plz help me out. thank you.

    Read the article

< Previous Page | 567 568 569 570 571 572 573 574 575 576 577 578  | Next Page >