Search Results

Search found 9889 results on 396 pages for 'behind the compiler'.

Page 323/396 | < Previous Page | 319 320 321 322 323 324 325 326 327 328 329 330  | Next Page >

  • How to avoid multiple, unused has_many associations when using multiple models for the same entity (

    - by mikep
    Hello, I'm looking for a nice, Ruby/Rails-esque solution for something. I'm trying to split up some data using multiple tables, rather than just using one gigantic table. My reasoning is pretty much to try and avoid the performance drop that would come with having a big table. So, rather than have one table called books, I have multiple tables: books1, books2, books3, etc. (I know that I could use a partition, but, for now, I've decided to go the 'multiple tables' route.) Each user has their books placed into a specific table. The actual book table is chosen when the user is created, and all of their books go into the same table. The goal is to try and keep each table pretty much even -- but that's a different issue. One thing I don't particularly want to have is a bunch of unused associations in the User class. Right now, it looks like I'd have to do the following: class User < ActiveRecord::Base has_many :books1, :books2, :books3, :books4, :books5 end class Books1 < ActiveRecord::Base belongs_to :user end class Books2 < ActiveRecord::Base belongs_to :user end First off, for each specific user, only one of the book tables would be usable/applicable, since all of a user's books are stored in the same table. So, only one of the associations would be in use at any time and any other has_many :bookX association that was loaded would be a waste. I don't really know Ruby/Rails does internally with all of those has_many associations though, so maybe it's not so bad. But right now I'm thinking that it's really wasteful, and that there may just be a better, more efficient way of doing this. Is there's some sort of special Ruby/Rails methodology that could be applied here to avoid having to have all of those has_many associations? Also, does anyone have any advice on how to abstract the fact that there's multiple book tables behind a single books model/class?

    Read the article

  • PDCurses TUI with C++ Win32 console application

    - by Bach
    I have downloaded pdcurses source and was able to successfully include curses.h in my project, linked the pre-compiled library and all good. After few hours of trying out the library, I saw the tuidemo.c in the demos folder, compiled it into an executable and brilliant! exactly what I needed for my project. Now the problem is that it's a C code, and I am working on a C++ project in VS c++ 2008. The files I need are tui.c and tui.h How can I include that C file in my C++ code? I saw few suggestions here but the compiler was not too happy with 100's of warnings and errors. How can I go on including/using that TUI pdcurses includes!? Thanks EDIT: I added extern "C" statement, so my test looks like this now, but I'm getting some other type of error #include <stdio.h> #include <stdlib.h> using namespace std; extern "C" { #include <tui.h> } void sub0(void) { //do nothing } void sub1(void) { //do nothing } int main (int argc, char * const argv[]) { menu MainMenu[] = { { "Asub", sub0, "Go inside first submenu" }, { "Bsub", sub1, "Go inside second submenu" }, { "", (FUNC)0, "" } /* always add this as the last item! */ }; startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); return 0; } Although it is compiling successfully, it is throwing an Error at runtime: 0xC0000005: Access violation reading location 0x021c52f9 at line startmenu(MainMenu, "TUI - 'textual user interface' demonstration program"); Not sure where to go from here. thanks again.

    Read the article

  • Enforce strong type checking in C (type strictness for typedefs)

    - by quinmars
    Is there a way to enforce explicit cast for typedefs of the same type? I've to deal with utf8 and sometimes I get confused with the indices for the character count and the byte count. So it be nice to have some typedefs: typedef unsigned int char_idx_t; typedef unsigned int byte_idx_t; With the addition that you need an explicit cast between them: char_idx_t a = 0; byte_idx_t b; b = a; // compile warning b = (byte_idx_t) a; // ok I know that such a feature doesn't exist in C, but maybe you know a trick or a compiler extension (preferable gcc) that does that. EDIT: I still don't really like the Hungarian notation in general, I couldn't used it for this problem because of project coding conventions, but I used it now in another similar case, where also the types are the same and the meanings are very similar. And I have to admit: it helps. I never would go and declare every integer with a starting "i", but as in Joel's example for overlapping types, it can be life saving.

    Read the article

  • Making Javascript and HTML5 games

    - by Jeff Meatball Yang
    A long time ago (Netscape 4-era), I wrote Javascript-based games: Pong, Minesweeper, and John Conway's Life among them. I'm getting back into it, and want to get my hands even dirtier. I have a few games in mind: Axis & Allies clone, with rugged maps and complex rules. Tetris clone, possibly with real-time player-vs-player or player-vs-computer mode Breakout clone, with a couple weapons and particle velocities In all of these, I have only a few objectives: Use JavaScript and HTML 5 - it should run on Chrome, Safari, or maybe an iPad. Start small and simple, then build-up features. Learn something new about game design and implementation. So my questions are: How would you implement these games? Do you have any technology recommendations? If you've written these games, what was the hardest part? N.B. I also want to start from first-principles - if you recommend a framework/library, I would appreciate some theory or implementation details behind it. These games are different enough that I should learn something new from each one.

    Read the article

  • Magic Methods in Python

    - by dArignac
    Howdy, I'm kind of new to Python and I wonder if there is a way to create something like the magic methods in PHP (http://www.php.net/manual/en/language.oop5.overloading.php#language.oop5.overloading.methods) My aim is to ease the access of child classes in my model. I basically have a parent class that has n child classes. These classes have three values, a language key, a translation key and a translation value. The are describing a kind of generic translation handling. The parent class can have translations for different translation key each in different languages. E.g. the key "title" can be translated into german and english and the key "description" too (and so far and so on) I don't want to get the child classes and filter by the set values (at least I want but not explicitly, the concrete implementation behind the magic method would do this). I want to call parent_class.title['de'] # or also possible maybe parent_class.title('de') for getting the translation of title in german (de). So there has to be a magic method that takes the name of the called method and their params (as in PHP). As far as I dug into Python this is only possible with simple attributes (_getattr_, _setattr_) or with setting/getting directly within the class (_getitem_, _setitem_) which both do not fit my needs. Maybe there is a solution for this? Please help! Thanks in advance!

    Read the article

  • Crosshairs in Java

    - by typoknig
    I am making a game that needs a crosshair. I have been playing with the java.awt.cursor class and that is easy enough, but the problem is that I do not want the crosshairs to be able to leave the window I create for my game, so I tried this instead: private void drawCrossHair(Graphics g){ Ellipse2D ellipse = new Ellipse2D.Float(); ellipse.setFrame(crossHair.x, crossHair.y, 36, 36); Color yellow = new Color (0xEDFF62); g.setColor(yellow); g.fillOval(crossHair.x, crossHair.y, 40, 40); g.setClip(ellipse); g.clip(ellipse); Basically I am trying to remove the "ellipse" from "g" leaving only a small ring behind. The problem here is that "g.clip(ellipse);" gives me an error. My objective with this code is to create a circle with a transparent center, like a donut. Once the donut is created I will add some small points on the inside of it so it looks more like crosshairs. One thing that may or may not be an issue is that I plan on moving the crosshairs with a joystick, not a mouse... I do not know if that will limit my options for what kind of object my crosshairs can be.

    Read the article

  • Error when compiling a WinForms project that uses SubSonic library

    - by Mike Devenney
    The code generation is working but I get the following errors when I try to build the project: Error 4 Source file '...Project Path...\Structs.cs' could not be opened ('Unspecified error ') PPSGenerator Error 5 Source file '...Project Path...\Context.cs' could not be opened ('Unspecified error ') PPSGenerator Error 6 Source file '...Project Path...\ActiveRecord.cs' could not be opened ('Unspecified error ') PPSGenerator Error 7 Source file '...Project Path...\StoredProcedures.cs' could not be opened ('Unspecified error ') PPSGenerator I'm using VS2010 on a Windows 7 64 bit machine. Project is targeting Framework 3.5... any ideas? Also noticed the following warnings, but not sure that these are as important: Warning 1 The C# 2.0 and C# 3.5 compilers are no longer supported. Templates will always be compiled with the version 4 compiler instead of 'v3.5' as specified. ...ProjectPath...\Structs.tt 1 4 Warning 2 Multiple template directives were found in the template. All but the first one will be ignored. Multiple parameters to the template directive should be specified within one template directive. ...ProjectPath...\Settings.ttinclude 1 4 Warning 3 Compiling transformation: The variable 'parameters' is assigned but its value is never used ...ProjectPath...\SQLServer.ttinclude 92 15 Thanks! Mike D

    Read the article

  • Destructors not called when native (C++) exception propagates to CLR component

    - by Phil Nash
    We have a large body of native C++ code, compliled into DLLs. Then we have a couple of dlls containing C++/CLI proxy code to wrap the C++ interfaces. On top of that we have C# code calling into the C++/CLI wrappers. Standard stuff, so far. But we have a lot of cases where native C++ exceptions are allowed to propagate to the .Net world and we rely on .Net's ability to wrap these as System.Exception objects and for the most part this works fine. However we have been finding that destructors of objects in scope at the point of the throw are not being invoked when the exception propagates! After some research we found that this is a fairly well known issue. However the solutions/ workarounds seem less consistent. We did find that if the native code is compiled with /EHa instead of /EHsc the issue disappears (at least in our test case it did). However we would much prefer to use /EHsc as we translate SEH exceptions to C++ exceptions ourselves and we would rather allow the compiler more scope for optimisation. Are there any other workarounds for this issue - other than wrapping every call across the native-managed boundary in a (native) try-catch-throw (in addition to the C++/CLI layer)?

    Read the article

  • Why do mozilla and webkit prepend -moz- and -webkit- to CSS3 rules?

    - by egarcia
    CSS3 rules bring lots of interesting features. Take border-radius, for example. The standard says that if you write this rule: div.rounded-corners { border-radius: 5px; } I should get a 5px border radius. But neither mozilla nor webkit implement this. However, they implement the same thing, with the same parameters, with a different name (-moz-border-radius and -webkit-border-radius, respectively). In order to satisfy as many browsers as possible, you end up with this: div.rounded-corners { border-radius: 5px; -moz-border-radius: 5px; -webkit-border-radius: 5px; } I can see two obvious disadvantages: Copy-paste code. This has obvious risks that I will not discuss here. The W3C CSS validator will not validate these rules. At the same time, I don't see any obvious advantages. I believe that the people behind mozilla and webkit are more intelligent than myself. There must be some good reasons to have things structured this way. It's just that I can't see them. So, I must ask you people: why is this?

    Read the article

  • Compile time float packing/punning

    - by detly
    I'm writing C for the PIC32MX, compiled with Microchip's PIC32 C compiler (based on GCC 3.4). My problem is this: I have some reprogrammable numeric data that is stored either on EEPROM or in the program flash of the chip. This means that when I want to store a float, I have to do some type punning: typedef union { int intval; float floatval; } IntFloat; unsigned int float_as_int(float fval) { IntFloat intf; intf.floatval = fval; return intf.intval; } // Stores an int of data in whatever storage we're using void StoreInt(unsigned int data, unsigned int address); void StoreFPVal(float data, unsigned int address) { StoreInt(float_as_int(data), address); } I also include default values as an array of compile time constants. For (unsigned) integer values this is trivial, I just use the integer literal. For floats, though, I have to use this Python snippet to convert them to their word representation to include them in the array: import struct hex(struct.unpack("I", struct.pack("f", float_value))[0]) ...and so my array of defaults has these indecipherable values like: const unsigned int DEFAULTS[] = { 0x00000001, // Some default integer value, 1 0x3C83126F, // Some default float value, 0.005 } (These actually take the form of X macro constructs, but that doesn't make a difference here.) Commenting is nice, but is there a better way? It's be great to be able to do something like: const unsigned int DEFAULTS[] = { 0x00000001, // Some default integer value, 1 COMPILE_TIME_CONVERT(0.005), // Some default float value, 0.005 } ...but I'm completely at a loss, and I don't even know if such a thing is possible. Notes Obviously "no, it isn't possible" is an acceptable answer if true. I'm not overly concerned about portability, so implementation defined behaviour is fine, undefined behaviour is not (I have the IDB appendix sitting in front of me). As fas as I'm aware, this needs to be a compile time conversion, since DEFAULTS is in the global scope. Please correct me if I'm wrong about this.

    Read the article

  • actionscript-3: refactor interface inheritance to get rid of ambiguous reference error

    - by maxmc
    hi! imagine there are two interfaces arranged via composite pattern, one of them has a dispose method among other methods: interface IComponent extends ILeaf { ... function dispose() : void; } interface ILeaf { ... } some implementations have some more things in common (say an id) so there are two more interfaces: interface ICommonLeaf extends ILeaf { function get id() : String; } interface ICommonComponent extends ICommonLeaf, IComponent { } so far so good. but there is another interface which also has a dispose method: interface ISomething { ... function dispose() : void; } and ISomething is inherited by ICommonLeaf: interface ICommonLeaf extends ILeaf, ISomething { function get id() : String; } As soon as the dispose method is invoked on an instance which implements the ICommonComponent interface, the compiler fails with an ambiguous reference error because ISomething has a method called dispose and ILeaf also has a dispose method, both living in different interfaces (IComponent, ISomething) within the inheritace tree of ICommonComponent. I wonder how to deal with the situation if the IComponent, the ILeaf and the ISomething can't change. the composite structure must also work for for the ICommonLeaf & ICommonComponent implementations and the ICommonLeaf & ICommonComponent must conform to the ISomething type. this might be an actionscript-3 specific issue. i haven't tested how other languages (for instance java) handle stuff like this.

    Read the article

  • How do you fix issues with the debugger for the Android plug-in for Eclipse not attaching?

    - by user279112
    I have been trying to program something for the Android mobile phone, using Eclipse and the Android plug-in for that IDE, and my debugger used to attach just fine. But then it has suddenly started having consistent issues attaching. I just get that message about how the process is waiting for the debugger attach, and then it just won't. What determines whether the attachment glitches so seems to have something to do with what the code is that I'm trying to debug, as it seems to be drastically more of an issue with some versions of my code than with others (on the same app). How do I fix this? Now before you answer, please understand that I have researched this issue already. I have found a couple of solutions that have worked with other people, but which do not work for me. One of which is setting the debuggable property in the main manifest file as true, and the other is going into Dev Tools and into some settings menu, and from there selecting the process and essentially saying to the fake phone, "Debug this process". Neither has really worked. Any other ideas? And just in case...I've run into one blasted technical issue like this after another trying to program for that stupid phone. And I'm not the only one who's having these issues; when I go online to research these issues, it is always very easy for me to find many people who have the same issues, and who are having to use the shottiest, sloppiest, most "ghetto" solutions to work around these issues. I know that many people have created good applications for that phone, but I don't see how I'm supposed to do that when the SDK and the plug-in just don't work half the time. Does anybody know how I may put all this trash behind me, once and for all? Thanks for your answers to either question!

    Read the article

  • Instantiating and starting a Scala Actor in a Map

    - by Bruce Ferguson
    I'm experimenting with a map of actors, and would like to know how to instantiate them and start them in one fell swoop... import scala.actors.Actor import scala.actors.Actor._ import scala.collection.mutable._ abstract class Message case class Update extends Message object Test { val groupings = "group1" :: "group2" :: "group3":: Nil val myActorMap = new HashMap[String,MyActor] def main(args : Array[String]) { groupings.foreach(group => myActorMap += (group -> new MyActor)) myActorMap("group2").start myActorMap("group2") ! Update } } class MyActor extends Actor { def act() { loop { react { case Update => println("Received Update") case _ => println("Ignoring event") } } } } The line: myActorMap("group2").start will grab the second instance, and let me start it, but I would like to be able to do something more like: groupings.foreach(group => myActorMap += (group -> (new MyActor).start)) but no matter how I wrap the new Actor, the compiler complains with something along the lines of: type mismatch; found : scala.actors.Actor required: com.myCompany.test.MyActor or various other complaints. I know it must be something simple to do with anonymous classes, but I can't see it right now. Any suggestions? Thanks in advance!!

    Read the article

  • Porting - Shared Memory x32 & x64 processes

    - by dpb
    A 32 bit host Windows application setups shared memory (using memory mapped file / CreateFileMapping() API), and then other 32 bit client processes use this shared memory to communicate with each other. I am planning to port the host application to 64 bit platform and once it is ready, I intend that both 32 bit and 64 bit client processes should be able to use the shared memory setup by the main 64 bit host application. The original code written for host x32 application uses "size_t" almost everywhere, since this differs from 4 bytes to 8 bytes as we move from x32 to x64, I am looking for replacing it. I intend to replace "size_t" by "unsigned long long", so that its size will be same on 32 bit & 64 bit. Can you please suggest me better alternative? Also, will the use of "unsigned long long" have performance impact on x32 app .. i guess yes? Research Done - Found very useful articles - a) 20 issue in porting from 32 bit to 64 bit (www.viva64.com) b) No way to restrict/change "size_t" on x64 platform to 4 bytes using compiler flags or any hooks/crooks since it is typedef

    Read the article

  • How to remove Region and add new ContentControls from Module

    - by Jeaffrey Gilbert
    I've set only one region in Shell "LoginRegion" <!-- Login Region --> <Border Grid.Row="0"> <ContentControl x:Name="LoginRegion" Regions:RegionManager.RegionName="LoginRegion" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch"/> </Border> And after login succeeded, I need to remove "LoginRegion" and add 3 other regions with new LayoutRoot grid definitions to Shell from code behind in Login module. <Grid.RowDefinitions> <RowDefinition Height="93"/> <RowDefinition /> <RowDefinition Height="24"/> </Grid.RowDefinitions> <!-- Top Region --> <Border Grid.Row="0"> <ContentControl x:Name="TopRegion" Regions:RegionManager.RegionName="TopRegion" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch"/> </Border> <!-- Main Region --> <Border Grid.Row="1"> <ContentControl x:Name="MainRegion" Regions:RegionManager.RegionName="MainRegion" Style="{StaticResource TestStyle}" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch"/> </Border> <!-- Bottom Region --> <Border Grid.Row="2"> <ContentControl x:Name="BottomRegion" Regions:RegionManager.RegionName="BottomRegion" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch"/> </Border> Please help, thank you.

    Read the article

  • Setting an Excel Range with an Array using Python and comtypes?

    - by technomalogical
    Using comtypes to drive Python, it seems some magic is happening behind the scenes that is not converting tuples and lists to VARIANT types: # RANGE(“C14:D21”) has values # Setting the Value on the Range with a Variant should work, but # list or tuple is not getting converted properly it seems >>>from comtypes.client import CreateObject >>>xl = CreateObject("Excel.application") >>>xl.Workbooks.Open(r'C:\temp\my_file.xlsx') >>>xl.Visible = True >>>vals=tuple([(x,y) for x,y in zip('abcdefgh',xrange(8))]) # creates: #(('a', 0), ('b', 1), ('c', 2), ('d', 3), ('e', 4), ('f', 5), ('g', 6), ('h', 7)) >>>sheet = xl.Workbooks[1].Sheets["Sheet1"] >>>sheet.Range["C14","D21"].Value() (('foo',1),('foo',2),('foo',3),('foo',4),('foo',6),('foo',6),('foo',7),('foo',8)) >>>sheet.Range["C14","D21"].Value[()] = vals # no error, this blanks out the cells in the Range According to the comtypes docs: When you pass simple sequences (lists or tuples) as VARIANT parameters, the COM server will receive a VARIANT containing a SAFEARRAY of VARIANTs with the typecode VT_ARRAY | VT_VARIANT. This seems to be inline with what MSDN says about passing an array to a Range's Value. I also found this page showing something similar in C#. Can anybody tell me what I'm doing wrong? EDIT I've come up with a simpler example that performs the same way (in that, it does not work): >>>from comtypes.client import CreateObject >>>xl = CreateObject("Excel.application") >>>xl.Workbooks.Add() >>>sheet = xl.Workbooks[1].Sheets["Sheet1"] # at this point, I manually typed into the range A1:B3 >>> sheet.Range("A1","B3").Value() ((u'AAA', 1.0), (u'BBB', 2.0), (u'CCC', 3.0)) >>>sheet.Range("A1","B3").Value[()] = [(x,y) for x,y in zip('xyz',xrange(3))] # Using a generator expression, per @Mike's comment # However, this still blanks out my range :(

    Read the article

  • Explicit localization problem

    - by X-Dev
    when trying to translate the confirmation message to Norwegian i get the following error: Cannot have more than one binding on property 'OnClientClick' on 'System.Web.UI.WebControls.LinkButton'. Ensure that this property is not bound through an implicit expression, for example, using meta:resourcekey. i use Explicit localization in the following manner: <asp:LinkButton ID="lnkMarkInvoiced" runat="server" OnClick="lnkMarkInvoiced_OnClick" OnClientClick="<%# Resources: lnkMarkInvoicedResource.OnClientClick%>" Visible="False" CssClass="stdtext" meta:resourcekey="lnkMarkInvoicedResource" ></asp:LinkButton> here's the local resource file entry: <data name="lnkMarkInvoicedResource.OnClientClick" xml:space="preserve"> <value>return confirm('Er du sikker?');</value> if i remove the meta attribute i get the English text(default). how do i get the Norwegian text appearing without resorting to using the code behind? Update: removing the meta attribute prevents the exception from occurring but the original problem still exists. I can't get the Norwegian text to show. only the default English text shows. Another Update: I know this question is getting old but i still can't get the Norwegian text to display. If anyone has some tips please post a response.

    Read the article

  • can not override showDialog in Activity tab

    - by hornetbzz
    Trying to downgrade my appl from android 2.2 (API 8) down to android 2.1 (API7), I'm facing some issues with dialog boxes. Based on this thread, I'm trying to catch these exceptions but can't override the showDialog method. I turned the Java compiler from 1.5 to 1.6 according to this answer to a similar issue, but no changes, Eclipse still returns : Cannot override the final method from Activity public class MyActivity extends Activity implements SeekBar.OnSeekBarChangeListener { // ... some stuffs @Override // here is the issue public void showDialog(int dialogId) { try { super.showDialog(dialogId); } catch (IllegalArgumentException e) { Log.e(ACTIVITY_TAG, "Error dialog"); } } @Override protected Dialog onCreateDialog(int id) { switch (id) { case DIALOG_ALERT: // Create out AlertDialog Builder builder = new AlertDialog.Builder(this); builder.setMessage(msg); builder.setCancelable(false); builder.setPositiveButton(GOTO_BOOK, new OkOnClickListener()); builder.setNegativeButton(STAY_HERE, new CancelOnClickListener()); AlertDialog dialog = builder.create(); dialog.show(); break; case DIALOG_ONCREATE: // Create out AlertDialog during the "onCreate" method (only "Ok" // button) Builder builder2 = new AlertDialog.Builder(getParent()); builder2.setMessage(msg); builder2.setCancelable(false); builder2.setPositiveButton(GO_BACK, new OkOnClickListener()); AlertDialog dialog2 = builder2.create(); dialog2.show(); break; } return super.onCreateDialog(id); } // ... some stuffs }

    Read the article

  • how avoids deadlock condition

    - by rima
    Hi I try to write a program like a compiler.In this case I must simulate these codes of SQLPL(This one can be just for example).for example in command prompt i wana do these: c:\> sqlplus .... Enter User-Name:(here we must enter username) xxxx Enter password:(same up)yyyyy ... sql>(now i want to send my sql command to shell)prompt "rima"; "rima" [<-output] sql> prompt "xxxx" sql> exit very simple. I try to use this code: ProcessStartInfo psi = new ProcessStartInfo( @"sqlplus"); psi.UseShellExecute = false; psi.CreateNoWindow = true; psi.RedirectStandardInput = true; psi.RedirectStandardOutput = true; //psi.RedirectStandardError = true; Process process = new Process(); process.StartInfo = psi; bool started = process.Start(); if (started) { process.StandardInput.WriteLine("user/password"); process.StandardInput.Flush(); string ret = process.StandardOutput.ReadLine(); // <-- stalls here System.Console.WriteLine("sqlplus says :" + ret + "\"."); } i find out it form here but as if u read this code has problem!DEADLOCK Condition problem! this is my second time i ask my question,every time my knowledge growing,but i cant get how I can solve my problem at last!!! So I kindly kiss your hand,please help me,these process is not clear for me.any one can give me a code that handle my problem?Already i look at all codes,also I try to use ProcessRunner that in my last post some one offer me,but I cant use it also,i receive an error. I hope by first example u find out what i want,and solve the second code problem... thanks I use C# for implemantation

    Read the article

  • Problem with UserControl with custom Dependency Property

    - by Mathias Koch
    Hi, I'm writing a user control with a dependency property for a search text called SearchText. It is a dependency property because I want to allow consumers of the control to use data binding. The user control contains a WPF TextBox where the user can enter the search text. I could use data binding to connect the SearchText dependency property of the user control with the Text dependency property of the TextBox, but this binding only fires when the text box looses input focus. What I want is SearchText to be updated after every change of Text. So I have added a TextChanged event handler to the user control where I set SearchText to the value of Text. My Problem is, the SearchText binding doesn't work, the source never gets updated. What am I doing wrong? Here's the relevant part of the user controls code-behind: public partial class UserControlSearchTextBox : UserControl { public string SearchText { get { return (string)GetValue(SearchTextProperty); } set { SetValue(SearchTextProperty, value); } } public static readonly DependencyProperty SearchTextProperty = DependencyProperty.Register("SearchText", typeof(string), typeof(UserControlSearchTextBox), new UIPropertyMetadata("")); private void TextBox_TextChanged(object sender, TextChangedEventArgs e) { SearchText = ((TextBox)sender).Text; } ... } The window that contains an instance of the user control has its DataContext set to an object that has a property also called SearchText. <uc:UserControlSearchTextBox SearchText="{Binding SearchText}" /> The data context of the Window: public class DataSourceUserManual : DataSourceBase { private string _searchText; public string SearchText { get { return _searchText; } set { _searchText = value; ... OnPropertyChanged("SearchText"); } } } Unfortunately, this setter is not called when I type into the text box. Any ideas?

    Read the article

  • A little confusion about AJAX and inserting into DOM..

    - by Gnee
    I have this working great, but I'd like a deeper understanding of what is actually going on behind the scenes. I am using Jquery's Ajax method to pull 5 blog posts (returning only the title and first photo). A PHP script grabs the blog posts' title and first photo and sticks it in an array and sends it back to my browser as JSON. Upon receiving the JSON object, Jquery grabs the first member of the JSON object and displays it's title and photo. In a gallery I made, using buttons – the user can iterate the 1-5 posts. So the actual AJAX call happens right away, and only once. I am basically using this kind of setup: $('my_div').html(json_obj[i]) and each click does a i++. So jquery is plucking these blog posts from my computers memory, my web browsers cache, or some kind of cache in the Javascript engine? One of the things it's returning is a pretty gnarly animated gif. I just wonder if it constantly running in the background (but not visible), stealing processing cycles...etc. Or Javascript just inserting (say a flash movie) into the DOM, but before hand does nothing but take up a little memory (no processing). Anyway, I'm just curious. If someone is a guru on this, I'd love to hear your take. THanks!!

    Read the article

  • Strange Behaviour in Swift: constant defined with LET but behaving like a variable defined with VAR

    - by Sam
    Stuck on the below for a day! Any insight would be greatly appreciated. The constant in the first block match0 behaves as expected. The constant defined in the second block does not behave as nicely in the face of a change to its "source": var str = "+y+z*1.0*sum(A1:A3)" if let range0 = str.rangeOfString("^\\+|^\\-|^\\*|^\\/", options: NSStringCompareOptions.RegularExpressionSearch){ let match0 = str[range0] println(match0) //yields "+" - as expexted str.removeRange(range0) println(match0) //yields "+" - as expected str.removeRange(range0) println(match0) //yields "+" - as expected } if let range1 = str.rangeOfString("^\\+|^\\-|^\\*|^\\/", options: NSStringCompareOptions.RegularExpressionSearch){ let match1 = str[range1] println(match1) //yields "+" as expected str.removeRange(range1) println(match1) //!@#$ OMG!!!!!!!!!!! a constant variable has changed! This prints "z" } The following are the options I can see: match1 has somehow obtained a reference to its source instead of being copied by value [Problem: Strings are value types in Swift] match1 has somehow obtained a closure to its source instead of just being a normal constant/variable? [Problem: sounds like science fiction & then why does match0 behave so well?] Could there be a bug in the Swift compiler? [Problem: Experience has taught me that this is very very very rarely the solution to your problem...but it is still in beta]

    Read the article

  • A monkey could do this better - Access to and availability of private member functions in C++

    - by David
    I am wandering the desert of my brain. I'm trying to write something like the following: class MyClass { // Peripherally Related Stuff public: void TakeAnAction(int oneThing, int anotherThing) { switch(oneThing){ case THING_A: TakeThisActionWith(anotherThing); break; //cases THINGS_NOT_A: }; private: void TakeThisActionWith(int thing) { string outcome = new string; outcome = LookUpOutcome(thing); // Do some stuff based on outcome return; } string LookUpOutcome(int key) { string oc = new string; oc = MyPrivateMap[key]; return oc; } map<int, string> MyPrivateMap; Then in the .cc file where I am actually using these things, while compiling the TakeAnAction section, it [CC, the solaris compiler] throws an an error: 'The function LookUpOutcome must have a prototype' and bombs out. In my header file, I have declared 'string LookUpOutcome(int key);' in the private section of the class. I have tried all sorts of variations. I tried to use 'this' for a little while, and it gave me 'Can only use this in non-static member function.' Sadly, I haven't declared anything static and these are all, putatively, member functions. I tried it [on TakeAnAction and LookUp] when I got the error, but I got something like, 'Can't access MyPrivateMap from LookUp'. MyPrivateMap could be made public and I could refer to it directly, I guess, but my sensibility says that is not the right way to go about this [that means that namespace scoped helper functions are out, I think]. I also guess I could just inline the lookup and subsequent other stuff, but my line-o-meter goes on tilt. I'm trying desperately not to kludge it.

    Read the article

  • Pass Parameter to Subroutine in Codebehind

    - by Sanjubaba
    I'm trying to pass an ID of an activity (RefNum) to a Sub in my codebehind. I know I'm supposed to use parentheses when passing parameters to subroutines and methods, and I've tried a number of ways and keep receiving the following error: BC30203: Identifier expected. I'm hard-coding it on the front-end just to try to get it to pass [ OnDataBound="FillSectorCBList("""WK.002""")" ], but it's obviously wrong. :( Front-end: <asp:DetailsView ID="dvEditActivity" AutoGenerateRows="False" DataKeyNames="RefNum" OnDataBound="dvSectorID_DataBound" OnItemUpdated="dvEditActivity_ItemUpdated" DataSourceID="dsEditActivity" > <Fields> <asp:TemplateField> <ItemTemplate> <br /><span style="color:#0e85c1;font-weight:bold">Sector</span><br /><br /> <asp:CheckBoxList ID="cblistSector" runat="server" DataSourceID="dsGetSectorNames" DataTextField="SectorName" DataValueField="SectorID" OnDataBound="FillSectorCBList("""WK.002""")" ></asp:CheckBoxList> <%-- Datasource to populate cblistSector --%> <asp:SqlDataSource ID="dsGetSectorNames" runat="server" ConnectionString="<%$ ConnectionStrings:dbConn %>" ProviderName="<%$ ConnectionStrings:dbConn.ProviderName %>" SelectCommand="SELECT SectorID, SectorName from Sector ORDER BY SectorID"></asp:SqlDataSource> </ItemTemplate> </asp:TemplateField> </Fields> </asp:DetailsView> Code-behind: Sub FillSectorCBList(ByVal RefNum As String, ByVal sender As Object, ByVal e As System.EventArgs) Dim SectorIDs As New ListItem Dim myConnection As String = ConfigurationManager.ConnectionStrings("dbConn").ConnectionString() Dim objConn As New SqlConnection(myConnection) Dim strSQL As String = "SELECT DISTINCT A.RefNum, AS1.SectorID, S.SectorName FROM Activity A LEFT OUTER JOIN Activity_Sector AS1 ON AS1.RefNum = A.RefNum LEFT OUTER JOIN Sector S ON AS1.SectorID = S.SectorID WHERE A.RefNum = @RefNum ORDER BY A.RefNum" Dim objCommand As New SqlCommand(strSQL, objConn) objCommand.Parameters.AddWithValue("RefNum", RefNum) Dim ad As New SqlDataAdapter(objCommand) Try [Code] Finally [Code] End Try objCommand.Connection.Close() objCommand.Dispose() objConn.Close() End Sub Any advice would be great. I'm not sure if I even have the right approach. Thank you!

    Read the article

  • Is NUnit's ExpectedExceptionAttribute only way to test if something raises an exception?

    - by Dariusz Walczak
    Hello, I'm completely new at C# and NUnit. In Boost.Test there is a family of BOOST_*_THROW macros. In Python's test module there is TestCase.assertRaises method. As far as I understand it, in C# with NUnit (2.4.8) the only method of doing exception test is to use ExpectedExceptionAttribute. Why should I prefer ExpectedExceptionAttribute over - let's say - Boost.Test's approach? What reasoning can stand behind this design decision? Why is that better in case of C# and NUnit? Finally, if I decide to use ExpectedExceptionAttribute, how can I do some additional tests after exception was raised and catched? Let's say that I want to test requirement saying that object has to be valid after some setter raised System.IndexOutOfRangeException. How would you fix following code to compile and work as expected? [Test] public void TestSetterException() { Sth.SomeClass obj = new SomeClass(); // Following statement won't compile. Assert.Raises( "System.IndexOutOfRangeException", obj.SetValueAt( -1, "foo" ) ); Assert.IsTrue( obj.IsValid() ); } Edit: Thanks for your answers. Today, I've found an It's the Tests blog entry where all three methods described by you are mentioned (and one more minor variation). It's shame that I couldn't find it before :-(.

    Read the article

< Previous Page | 319 320 321 322 323 324 325 326 327 328 329 330  | Next Page >