Search Results

Search found 6258 results on 251 pages for 'trouble'.

Page 216/251 | < Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >

• Intercept creation of activities when the application is restored

  - by Johan Bilien

  Most of our activities access a user-specific model. All these activities inherit from a ModelActivity base class, which provides a getModel() call. When one of these activities detect that the user has signed out (through the AccountManager callback), it sticks to its existing model, but prepares to exit back to the root activity (which is not user-specific) by starting its intent with FLAG_ACTIVITY_CLEAR_TOP. If however the user deletes an account while the app is not running, we run into trouble when the activity is restored. Now the activity needs to handle there not being a model, which makes the code more complicated and bug-prone. Ideally we would intercept the application restore process before the activity is created. Then we would check whether we have an account and a model, and if not clear up the saved stack of activities, and restart from our root activity instead of the last saved activity. But as far as I can tell the first place where we can run code is in the onCreate callback of the activity. Is there a way to run some code when the application is restored from background-saving, but before the saved activity is created?

  Read the article

• regexp to match string with (comma-separated) number at start and to split into number and rest?

  - by mix

  Given a string such as: 23,234,456 first second third How can I split string this into two parts, where part 1 contains the number at the beginning and part 2 contains the rest---but only if the string STARTS with a number, and the number can be comma-separated or not? In other words, I want two results: 23,234,456 and first second third. If there's a number in that string that isn't part of the first number then it should be in the second result. My best stab at this so far, to grab the number at the beginning, is something like this: ^[0-9]+(,[0-9]{3})* Which seems to grab a comma-separated or non-comma-separated number that starts the line. However, when I run this in the Javascript console I get not only the full number, but also a match on just the last 3 digits with their preceeding ,. (e.g. 23,234,456 and ,456). As for getting the rest into another var I'm having trouble. I tried working with \b, etc., but I think I must be missing something fundamental about grabbing the rest of the line. I'm doing this in Javascript in case it matters. More examples of what to match and what not to match. 2 one two three should return 2 and one two three 2345 one two three should return 2345 and one two three 2 one 2 three should return 2 and one 2 three 2,234 one two 3,000 should return 2,234 and one two 3,000 The space between parts 1 and two could be included in the beginning of part 2.

  Read the article

• Two references to the same domain/entity model

  - by Sbossb

  Problem I want to save the attributes of a model that have changed when a user edits them. Here's what I want to do ... Retrieve edited view model Get domain model and map back updated value Call the update method on repository Get the "old" domain model and compare values of the fields Store the changed values (in JSON) into a table However I am having trouble with step number 4. It seems that the Entity Framework doesn't want to hit the database again to get the model with the old values. It just returns the same entity I have. Attempted Solutions I have tried using the Find() and the SingleOrDefault() methods, but they just return the model I currently have. Example Code private string ArchiveChanges(T updatedEntity) { //Here is the problem! //oldEntity is the same as updatedEntity T oldEntity = DbSet.SingleOrDefault(x => x.ID == updatedEntity.ID); Dictionary<string, object> changed = new Dictionary<string, object>(); foreach (var propertyInfo in typeof(T).GetProperties()) { var property = typeof(T).GetProperty(propertyInfo.Name); //Get the old value and the new value from the models var newValue = property.GetValue(updatedEntity, null); var oldValue = property.GetValue(oldEntity, null); //Check to see if the values are equal if (!object.Equals(newValue, oldValue)) { //Values have changed ... log it changed.Add(propertyInfo.Name, newValue); } } var ser = new System.Web.Script.Serialization.JavaScriptSerializer(); return ser.Serialize(changed); } public override void Update(T entityToUpdate) { //Do something with this string json = ArchiveChanges(entityToUpdate); entityToUpdate.AuditInfo.Updated = DateTime.Now; entityToUpdate.AuditInfo.UpdatedBy = Thread.CurrentPrincipal.Identity.Name; base.Update(entityToUpdate); }

  Read the article

• Google Chrome forgetting registration cookie immediately

  - by Ryan Giglio

  I'm having trouble with cookies on my site's registration form. When a user creates an account, PHP sets one cookie with their user id, and one cookie with a hash containing their user agent and a few other things. Both of these cookies are set to expire in an hour. This is the code that sets the cookie after creating your account $registerHash = hash( "sha512", $_SERVER['HTTP_USER_AGENT'] . $_SERVER['HTTP_HOST'] . $_SERVER['DOCUMENT_ROOT'] ); setcookie("register_user_id", $newUserID, time() + 7200, "/"); setcookie("register_hash", $registerHash, time() + 7200, "/"); The next page is a confirmation page which sends an email and then optionally lets the user go on to fill out more account information. If the user goes on to fill out more, it uses the cookie to know what account to save it to. It works correctly in Firefox and IE, but in Chrome the cookie is forgotten as soon as you go to the next page. The cookie simply doesn't exist. You can see the problem here: http://crewinyourcode.com/register/paid/ If you use Chrome, you will get a registration timeout error as soon as you try to advance past the confirmation page. However on Firefox it works fine.

  Read the article

• Converting IIS Redirect to .htaccess

  - by user1641321

  I am having trouble getting the rewrite to work on an apache server. The end result is so i can make subdomains on the fly just by adding a directory. For example anysubdomain.domain.com will redirect to domain.com/anysubdomain and still appear as anysubdomain.domain.com. Is there anyone out there that convert this for me? <rewrite> <rules> <rule name="Subdomain Redirect" patternSyntax="ECMAScript" stopProcessing="true"> <match url="^(.*)$" /> <conditions trackAllCaptures="true"> <add input="{HTTP_HOST}" pattern="^www\.obdevsite\.com" negate="true" /> <add input="{HTTP_HOST}" pattern="^(.*)\.obdevsite\.com" /> <add input="{REQUEST_URI}" pattern="^(.*)$" /> </conditions> <action type="Rewrite" url="/{C:1}/{C:2}" appendQueryString="false" /> </rule> </rules> </rewrite>

  Read the article

• Help with HTTP Intercepting Proxy in Ruby?

  - by Philip

  I have the beginnings of an HTTP Intercepting Proxy written in Ruby: require 'socket' # Get sockets from stdlib server = TCPServer.open(8080) # Socket to listen on port 8080 loop { # Servers run forever Thread.start(server.accept) do |client| puts "** Got connection!" @output = "" @host = "" @port = 80 while line = client.gets line.chomp! if (line =~ /^(GET|CONNECT) .*(\.com|\.net):(.*) (HTTP\/1.1|HTTP\/1.0)$/) @port = $3 elsif (line =~ /^Host: (.*)$/ && @host == "") @host = $1 end print line + "\n" @output += line + "\n" # This *may* cause problems with not getting full requests, # but without this, the loop never returns. break if line == "" end if (@host != "") puts "** Got host! (#{@host}:#{@port})" out = TCPSocket.open(@host, @port) puts "** Got destination!" out.print(@output) while line = out.gets line.chomp! if (line =~ /^<proxyinfo>.*<\/proxyinfo>$/) # Logic is done here. end print line + "\n" client.print(line + "\n") end out.close end client.close end } This simple proxy that I made parses the destination out of the HTTP request, then reads the HTTP response and performs logic based on special HTML tags. The proxy works for the most part, but seems to have trouble dealing with binary data and HTTPS connections. How can I fix these problems?

  Read the article

• Setting Cursor property has no effect (C#)

  - by Knarf Navillus

  Hello, I have a class that I've derived from System.Windows.Forms.Panel, and my application has a main form with one of these panels. On the whole, the panel works great! The only thing I'm having trouble with is setting the cursor. Whether I'm setting it to one of the static members of the Cursors class (Default, WaitCursor, etc.) or setting it to a custom cursor that I've loaded from a resource, the end result is the same: it does nothing. I still see the default mouse pointer, no matter what. This line of code is inside a method of my panel-derived class: this.Cursor = Cursors.WaitCursor; I can set a break point there, and see that this line is being hit when I expect it to. I've also created an override for the OnCursorChanged method, and set a breakpoint in there just to see if it's being triggered. I can verify that both breakpoints are being hit when I expect them to. However, the cursor just never changes. There must be something that I'm missing. Does anyone have any ideas? P.S. I also did try setting Current.Cursor as well, however that did not help.

  Read the article

• EF Code First, how can I achieve two foreign keys from one table to other table?

  - by Yoo Matsuo

  I've recently downloaded Entity Framework Code First CTP5, and have a trouble with this scenario. I have two tables as follows: Members table ID Name Comments table ID Comment CommentedMemberID CommentMemberID And, the data should be like the following: Members ID Name 1 Mike 2 John 3 Tom Comments ID Comment CommentedMemberID CommentMemberID 1 Good 1 2 2 Good 1 3 3 Bad 2 1 Then, I coded as shown below: public class Member { public int ID {get; set; } public string Name { get; set;} public virtual ICollection Comments { get; set;} } public class Comment { public int ID { get; set; } public string Comment { get; set; } public int CommentedMemberID { get; set; } public int CommentMemberID{ get; set; } public virtual Member CommentedMember { get; set; } public virtual Member CommentMember { get; set; } } public class TestContext : DbContext { public DbSet Members { get; set; } public DbSet Comments { get; set; } } But when I run these models on my cshtml, it gives me errors saying "Cannot create CommentMember instance" or something like that (Sorry, I already changed my models to proceed the EF Code First evaluation, so can't reproduce the same error). I've also tried to use OnModelCreating on the TestContext, but can't find any good instructions and don't know what to do. I saw a blog post of the EF Code First CTP3, and it seems there was a RelatedTo attribute in that version, but now it has gone. Could anyone know how to get it work properly? Or is this a totally wrong way to go with this scenario? Thanks, Yoo

  Read the article

• Making a Delete and Reply button in Jquery

  - by Branko Ostojic

  this is my second post on the website. Of all other sites i tried, this one gave the most accurate and useful information! I'm in a bit of a trouble with buttons, i have a task to make an inbox and to add a "reply" and "delete" button into every instance of the message. I was indeed wandering if there is a better way to do that than forcing the HTML code into the script, because every message is dynamically generated. Any help and/or suggestions would be very appreciated!(The objects are called from a JSON file). $(document).ready(function(){ $.getJSON('public/js/data.json', function(json){ $.each(json.data, function(i, data){ var output = ''; if(data.from.id != '234' && data.from.name != 'Alan Ford'){ $("#inbox").append( output += '<div class="post">'+ '<div class="h1">'+data.from.name+' - '+data.subject+'</div>'+ //this gives the name of the person who sent the message and the subject '<div class="content">'+data.message_formatted+'</div>'+ //The content of the message //buttons should be squeezed left of the date //this gives the date of the message sent '<div class="time">'+data.date_sent_formatted.formatted+'</div>'+ '</div>' ); }}); }); }); var date_sent=convertToDateTime(); function delete_message(id){ console.log('Delete message with id: '+id); } function reply_message(id, sender){ console.log('Message id: '+id); console.log('Reply to: '+sender); } The complete code in the JSFiddle . Just copy/pasted!

  Read the article

• Updating Cells in a DataTable

  - by Maxim Z.

  I'm writing a small app to do a little processing on some cells in a CSV file I have. I've figured out how to read and write CSV files with a library I found online, but I'm having trouble: the library parses CSV files into a DataTable, but, when I try to change a cell of the table, it isn't saving the change in the table! Below is the code in question. I've separated the process into multiple variables and renamed some of the things to make it easier to debug for this question. Code Inside the loop: string debug1 = readIn.Rows[i].ItemArray[numColumnToCopyTo].ToString(); string debug2 = readIn.Rows[i].ItemArray[numColumnToCopyTo].ToString().Trim(); string debug3 = readIn.Rows[i].ItemArray[numColumnToCopyFrom].ToString().Trim(); string towrite = debug2 + ", " + debug3; readIn.Rows[i].ItemArray[numColumnToCopyTo] = (object)towrite; After the loop: readIn.AcceptChanges(); When I debug my code, I see that towrite is being formed correctly and everything's OK, except that the row isn't updated: why isn't it working? I have a feeling that I'm making a simple mistake here: the last time I worked with DataTables (quite a long time ago), I had similar problems. If you're wondering why I'm adding another comma in towrite, it's because I'm combining a street address field with a zip code field - I hope that's not messing anything up. My code is kind of messy, as I'm only trying to edit one file to make a small fix, so sorry.

  Read the article

• Call 32-bit or 64-bit program from bootloader

  - by user1002358

  There seems to be quite a lot of identical information on the Internet about writing the following 3 bootloaders: Infinite loop jmp $ Print a single character Print "Hello World". This is fantastic, and I've gone through these 3 variations with very little trouble. I'd like to write some 32- or 64-bit code in C and compile it, and call that code from the bootloader... basically a bootloader that, for example, sets the computer up to run some simple numerical simulation. I'll start by listing primes, for example, and then maybe some input/output from the user to maybe compute a Fourier transform. I don't know. I haven't found any information on how to do this, but I can already foresee some problems before I even begin. First of all, compiling a C program compiles it into one of several different files, depending on the target. For Windows, it's a PE file. For Linux, it's a .out file. These files are both quite different. In my instance, the target isn't Windows or Linux, it's just whatever I have written in the bootloader. Secondly, where would the actual code reside? The bootloader is exactly 512 bytes, but the program I write in C will certainly compile to something much larger. It will need to sit on my (virtual) hard disk, probably in some sort of file system (which I haven't even defined!) and I will need to load the information from this file into memory before I can even think about executing it. But from my understanding, all this is many, many orders of magnitude more complex than a 12-line "Hello World" bootloader. So my question is: How do I call a large 32- or 64-bit program (written in C/C++) from my 16-bit bootloader.

  Read the article

• C++ Using a class from a header within a class

  - by Kotsuzui

  I'm having a bit of trouble with classes used within classes, from header files. I have an class time in time.h: class Time { private: int hour, second, minute; public: . . . int getHour(int h); etc. setHour(); etc. void print24hour(); // Prints time in 24 hour format } And then, main.cpp: #include "time.h" class Class { private: string name; double grade; Time startTime; Time endTime; public: Class(); ~Class(); void setName(); void setGrade(); etc. } int main() { //Need to print time in 24 hour format, but I don't know how. class[i].startTime.print24(getStartTime()); // ??? I'm rather lost } I get quite a few "hour, second, minute, etc." are private errors, I'm guessing I'm doing something simple in a rather wrong way. Please help.

  Read the article

• How to import 3rd party libraries

  - by Thahzan Mohomed

  I found some cool android libraries the other day and decided to try some. But I'm having trouble correctly importing the library. This is the URL of the library : https://github.com/dmytrodanylyk/android-process-button I first tried importing the library to eclipse (and move the files in java directory to src directory and set the project as library) and importing the sample to eclipse and set it to use the library project (Properties-Android-Libraries). But it didn't work. The layout files said it failed to instantiate [custom widget class]. The I tried importing the .jar file to libs directory (and update the java build path) but it didn't work either. It showed errors in the java files too. I then tried copying all the java and layout files to the sample project directory and it worked. But I'm guessing that's not the way to work with 3rd party libraries. I first thought it's some error with the library but all the other libraries I tried to import to my projects faced the same problem. Can someone walk me through how to correctly import a 3rd party library to my android project?

  Read the article

• Calling a method from another view in objective-c. (iphone sdk).

  - by MarcZero

  Hello. I am currently creating a multi-view game on the iPhone platform. I have my main view start to play some background music upon loading. I then go to another view and start the game. I am trying to get the background music from the original view to stop once I start the game. I am having trouble getting the stop playing music message to my original view. Here is the relevant info: The main view where the sound is played from is just a subView of the programViewController class called *viewController. The heading is in the programAppDelegate class. The sound is done using the AVAudioPlayer class and plays fine when the program starts up and when I navigate to other subviews that are added on by going through the menu system. In the view that I want to start the game, I attempt to call the instance of the class to turn of the player but anytime I use this format of code: [viewController #######]; It gives a build error of "viewController undeclared" no matter what I put after the "viewController" in the message.I have attempted to import the programAppDelegate.h file but it still gives the same error. I realize this might be a simple misunderstanding of the objective-c language but I cannot find any info on this issue. I am a recent convert from Java so I am trying to wrap my head around everything. Thank you for your time!

  Read the article

• Foiled by path-dependent types

  - by Ladlestein

  I'm having trouble using, in one trait, a Parser returned from a method in another trait. The compiler complains of a type mismatch and it appears to me that the problem is due to the path-dependent class. I'm not sure how to get what I want. trait Outerparser extends RegexParsers { def inner: Innerparser def quoted[T](something: Parser[T]) = "\"" ~> something <~ "\"" def quotedNumber = quoted(inner.number) // Compile error def quotedLocalNumber = quoted(number) // Compiles just fine def number: Parser[Int] = ("""[1-9][0-9]*"""r) ^^ {str => str.toInt} } trait Innerparser extends RegexParsers { def number: Parser[Int] = ("""[1-9][0-9]*"""r) ^^ {str => str.toInt} } And the error: [error] /Path/to/MyParser.scala:6: type mismatch [error] found : minerals.Innerparser#Parser[Int] [error] required: Outerparser.this.Parser[?] [error] def quotedNumber = quoted(inner.number) I sort-of get the idea: each "something" method is defining a Parser type whose path is specific to the enclosing class (Outerparser or Innerparser). The "quoted" method of Outerparser expects an an instance of type Outerparser.this.Parser but is getting Innerparser#Parser. I like to be able to use quoted with a parser obtained from this class or some other class. How can I do that?

  Read the article

• WPF A good way to make a view/edit control?

  - by Jefim

  Hi, this is just a question to discuss - what is the best way to make a view/edit control in WPF? E.g. we have an entity object Person, that has some props (name, surname, address, phone etc.). One presentation of the control would be a read-only view. And the other would have the edit view for this same person. Example: <UserControl x:Name="MyPersonEditor"> <Grid> <Grid x:Name="ViewGrid" Visibility="Visible"> <TextBlock Text="Name:"/> <TextBlock Text="{Binding Person.Name}"/> <Button Content="Edit" Click="ButtonEditStart_Click"/> </Grid> <Grid x:Name="EditGrid" Visibility="Collapsed"> <TextBlock Text="Name:"/> <TextBox Text="{Binding Person.Name}"/> <Button Content="Save" Click="ButtonEditEnd_Click"/> </Grid> </Grid> </UserControl> I hope that the idea is clear. The two options I see right now two grids with visibility switching and a TabControl without its header panel This is just a discussion question - not much trouble with it, yet I am just wondering if there are any other possibilities and elegant solutions to this.

  Read the article

• Binding Events rather than using onclick

  - by Abs

  Hello all, I have been told its better to bind events to elements rather than having onclicks with functions everywhere. I agree with this as it devolves more from the HTML which means cleaner and easier to debug code. But I am having trouble doing this! I loop through some data with PHP (see below) and I currently use onclick to call a function. How can I bind this onclick event to many elements using JQuery. <?php foreach($main_tags as $key=>$value){ ?> <li> <a id="<?php echo $key; ?>" href="#" onclick="tag_search('<?php echo $key; ?>'); return false;"> <?php echo $key; ?> <span class="num-active"> <?php echo $value; ?> </span> </a> </li> <?php } ?> Thanks all for any help

  Read the article

• Need help managing MySql connections

  - by David Jenings

  I'm having trouble finding a clear explanation of connection pooling. I'm building an app using the .NET connector I downloaded from mysql.com. The app only needs one db connection but will be running simultaneously on about 6 machines on my network. Normally, I'd create the connection at startup and just leave it. But I'm seeing lots of posts from people who say that's bad practice. Also I'm concerned about timeouts. My app will run 24/7 and there may be extended periods without database activity. I'm leaning toward the following: using (MySqlConnection conn = new MySqlConnection(connStr)) { conn.Open(); // use connection } But I'm not sure I understand what's going on in the background. Is this actually closing the connection and allowing gc to kill the object, or is there a built in pooling behavior that preserves the object and redelivers it the next time I try to create one? I certainly don't want the app reauthenticating across the network every time I hit the database. Can anyone offer me some advise?

  Read the article

• Select All in Javascript (Firefox extension) not working right

  - by leezer3

  I'm having some problems with a select all/ none function. (I didn't write it, I'm trying to fix it!) It currently looks like this: rsfindmod.SelAll = function(){ document.getElementById("ListBox").selectAll(); document.getElementById("ListBox").focus(); } It's being used on a dynamically generated set of links, so there's no set number of items in this listbox. This seems to work most of the time, but randomly it only selects those which are visible at the time. Scrolling the list or hitting the button again seems to normally make it work as expected. My first (Obvious?) thought was to replace the function entirely with the one from this link for testing: http://viralpatel.net/blogs/2009/06/listbox-select-all-move-left-right-up-down-javascript.html Trouble is that I can't get this one to work whatsoever! This gives me the error that listbox.options is not defined Any thoughts please? I'm by no means certain whether it's the original function at fault, or something in the generation of this listbox.

  Read the article

• jQuery toggle content-div from menubar

  - by nuclearsugar

  I'm having trouble getting jQuery to allow only one content-DIV to be visible at a time. So that clicking between the menu buttons (about, newsletter, contact) this will allow only one content-DIV to be visible. --- Then the content-DIV needs to hide when the associated menu button is clicked (like it does currently). --- Upon clicking the header 'alliteration', any content-DIVs that are open need to hide. http://home.jasonfletcher.info/all/alliteration/index.html $('#collapse_about').hide(); $('#collapse_newsletter').hide(); $('#collapse_contact').hide(); $('#menu1').click(function() { $('#collapse_about').slideToggle(400); return false; }); $('#menu2').click(function() { $('#collapse_newsletter').slideToggle(400); return false; }); $('#menu3').click(function() { $('#collapse_contact').slideToggle(400); return false; }); I understand that this is a pretty simple bit of code... but the form of it evades me. Any help is much appreciated.

  Read the article

• Difference between std::result_of and decltype

  - by Luc Touraille

  I have some trouble understanding the need for std::result_of in C++0x. If I understood correctly, result_of is used to obtain the resulting type of invoking a function object with certain types of parameters. For example: template <typename F, typename Arg> typename std::result_of<F(Arg)> invoke(F f, Arg a) { return f(a); } I don't really see the difference with the following code: template <typename F, typename Arg> auto invoke(F f, Arg a) -> decltype(f(a)) //uses the f parameter { return f(a); } or template <typename F, typename Arg> auto invoke(F f, Arg a) -> decltype(F()(a)); //"constructs" an F { return f(a); } The only problem I can see with these two solutions is that we need to either: have an instance of the functor to use it in the expression passed to decltype. know a defined constructor for the functor. Am I right in thinking that the only difference between decltype and result_of is that the first one needs an expression whereas the second does not?

  Read the article

• Why my jquery function is not firing on Firefox

  - by Cristian Boariu

  I have some trouble with some jquery method (for some checkboxes I want them to fire on checked/unchecked so I can do something then). This method works perfectly on Chrome and IE but not on latest FF. jQuery(function () { jQuery(':checkbox').change(function () { var counter = jQuery('.count').text(); var thisCheck = jQuery(this); if (thisCheck.is(':checked')) { counter++; //apply green color to the selected row jQuery(this).closest('tr').addClass('checked'); } else { counter--; //remove green color to the selected row jQuery(this).closest('tr').removeClass('checked'); } jQuery('.count').html(counter); //enable export button when there are selected emails to be exported if (counter > 0) { jQuery(".exportButton").removeAttr("disabled", ""); } else { jQuery(".exportButton").attr("disabled", "disabled"); } }); }); Basically it's simply not firing...Even with Debug is not catching the first line (function declare nor other lines too). If I move this javascript(without function declare) inside jQuery(document).ready(function ($) { all works nice on Firefox too... Yes, I do use jQuery.noConflict(); before jQuery(document).ready(function ($) { Do you know why this happens?

  Read the article

• how to reverse an angle

  - by MissHalberd

  I am no mathematician, but I somehow got into game development as a hobby. Having never studied anything beyond basic math, I have a lot of trouble figuring out how to reverse the angle of something, facing to the opposite direction, among the X axis. One image says more than 1000 words though (specially uneducated words): http://img156.imageshack.us/i/wihwin.png/ I basically want to reverse the direction of cannon objects adhered to a robot. When the robot changes from facing right to facing left, I do (180 - angle) as everyone suggested me, but it reverses the angle...literally, making the cannons aim up when they are aiming down. So, I need to do something else, but it escapes my knowledge. Anyone would be so kind to help me with this? Oh, I use regular C by the way, in case there's something built-in specific to it. To put it in other words, I work in 2D, so I want an angle that is facing right to face left. 0 being "totally to the right", 180 "left", 90 "up" and 270 "down". I want something that is aiming with an angle of 91 to turn into 89 when reversed, literally. There's no Z axis present. EDIT: Thanks for the answers! Trying them out now. I'll post which one worked in a minute!

  Read the article

• Sharing class member data between sub components

  - by Tim Gradwell

  I have an aggregate 'main' class which contains some data which I wish to share. The main class also has other class members. I want to share the data with these other class members. What is the correct / neatest way to do this? The specific example I have is as follows. The main class is a .net Form. I have some controls (actually controls within controls) on the main form which need access to the shared data. Main Form - DataX - DataY - Control1 -- Subcontrol1 - Control2 -- SubControl2 SubControls 1 and 2 both wish to access DataX and DataY. The trouble is, I feel like better practice (to reduce coupling), would be that either subcontrols should not know about Main Form, or Main Form should not know about subcontrols - probably the former. For subcontrols not to know about Main Form, would probably mean Main Form passing references to both Controls 1 and 2, which in turn would pass the references on to SubControls 1 and 2. Lots of lines of code which just forward the references. If I later added DataZ and DataW, and Controls 3 and 4 and SubControls 3 and 4, I'd have to add lots more reference forwarding code. It seems simpler to me to give SubControls 1 and 2 member references to Main Form. That way, any sub control could just ask for MainForm.DataX or MainForm.DataY and if I ever added new data, I could just access it directly from the sub controls with no hassle. But it still involves setting the 'MainForm' member references every time I add a new Control or Subcontrol. And it gives me a gut feeling of 'wrong'. As you might be able to tell I'm not happy with either of my solutions. Is there a better way? Thanks

  Read the article

• CArray doesn't call copy constructors on memory reallocations, now what?

  - by MMx

  Suppose I have a class that requires copy constructor to be called to make a correct copy of: struct CWeird { CWeird() { number = 47; target = &number; } CWeird(const CWeird &other) : number(other.number), target(&number) { } void output() { printf("%d %d\n", *target, number); } int *target, number; }; Now the trouble is that CArray doesn't call copy constructors on its elements when reallocating memory (only memcpy from the old memory to the new), e.g. this code CArray<CWeird> a; a.SetSize(1); a[0].output(); a.SetSize(2); a[0].output(); results in 47 47 -572662307 47 I don't get this. Why is it that std::vector can copy the same objects properly and CArray can't? What's the lesson here? Should I use only classes that don't require explicit copy constructors? Or is it a bad idea to use CArray for anything serious?

  Read the article

< Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >