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  • JQuery - Set TBODY

    - by Villager
    Hello, I have a table defined as follows: <table id="myTable" cellpadding="0" cellspacing="0"> <thead><tr> <th>Date</th> <th>First Name</th> <th>Last Name</th> </tr></thead> <tbody> <!-- rows will go here --> </tbody> </table> I am trying to dynamically populate 'myTable' at runtime via JavaScript. To accomodate for this, I am using JQuery. I want to write some HTML into the tbody element within 'myTable'. However, I am having problems understanding how to do this with the selectors. I know that I can get 'myTable' using: $("#myTable") I know that I can set the HTML of myTable by using the following: $("#myTable").html(someHtmlString); However, that sets the HTML of the entire table. In reality, I just want to set the HTML within the TBODY of 'myTable'. How do I do this with JQuery? Thank you!

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  • What is a good use case for static import of methods?

    - by Miserable Variable
    Just got a review comment that my static import of the method was not a good idea. The static import was of a method from a DA class, which has mostly static methods. So in middle of the business logic I had a da activity that apparently seemed to belong to the current class: import static some.package.DA.*; class BusinessObject { void someMethod() { .... save(this); } } The reviewer was not keen that I change the code and I didn't but I do kind of agree with him. One reason given for not static-importing was it was confusing where the method was defined, it wasn't in the current class and not in any superclass so it too some time to identify its definition (the web based review system does not have clickable links like IDE :-) I don't really think this matters, static-imports are still quite new and soon we will all get used to locating them. But the other reason, the one I agree with, is that an unqualified method call seems to belong to current object and should not jump contexts. But if it really did belong, it would make sense to extend that super class. So, when does it make sense to static import methods? When have you done it? Did/do you like the way the unqualified calls look? EDIT: The popular opinion seems to be that static-import methods if nobody is going to confuse them as methods of the current class. For example methods from java.lang.Math and java.awt.Color. But if abs and getAlpha are not ambiguous I don't see why readEmployee is. As in lot of programming choices, I think this too is a personal preference thing. Thanks for your response guys, I am closing the question.

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  • python recursive iteration exceeding limit for tree implementation

    - by user3698027
    I'm implementing a tree dynamically in python. I have defined a class like this... class nodeobject(): def __init__(self,presentnode=None,parent=None): self.currentNode = presentnode self.parentNode = parent self.childs = [] I have a function which gets possible childs for every node from a pool def findchildren(node, childs): # No need to write the whole function on how it gets childs Now I have a recursive function that starts with the head node (no parent) and moves down the chain recursively for every node (base case being the last node having no children) def tree(dad,children): for child in children: childobject = nodeobject(child,dad) dad.childs.append(childobject) newchilds = findchildren(child, children) if len(newchilds) == 0: lastchild = nodeobject(newchilds,childobject) childobject.childs.append(lastchild) loopchild = copy.deepcopy(lastchild) while loopchild.parentNode != None: print "last child" else: tree(childobject,newchilds) The tree formation works for certain number of inputs only. Once the pool gets bigger, it results into "MAXIMUM RECURSION DEPTH EXCEEDED" I have tried setting the recursion limit with set.recursionlimit() and it doesn't work. THe program crashes. I want to implement a stack for recursion, can someone please help, I have gone no where even after trying for a long time ?? Also, is there any other way to fix this other than stack ?

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  • Java: over-typed structures?

    - by HH
    Term over-type structure = a data structure that accepts different types, can be primitive or user-defined. I think ruby supports many types in structures such as tables. I tried a table with types 'String', 'char' and 'File' in Java but errs. How can I have over-typed structure in Java? How to show types in declaration? What about in initilization? Suppose a structure: INDEX VAR FILETYPE //0 -> file FILE //1 -> lineMap SizeSequence //2 -> type char //3 -> binary boolean //4 -> name String //5 -> path String Code import java.io.*; import java.util.*; public class Object { public static void print(char a) { System.out.println(a); } public static void print(String s) { System.out.println(s); } public static void main(String[] args) { Object[] d = new Object[6]; d[0] = new File("."); d[2] = 'T'; d[4] = "."; print(d[2]); print(d[4]); } } Errors Object.java:18: incompatible types found : java.io.File required: Object d[0] = new File("."); ^ Object.java:19: incompatible types found : char required: Object d[2] = 'T'; ^

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  • Javascript: click and dblclick deliver different parentNodes on same html. Why?

    - by user1658206
    currently I work on an very small wysiwyg editor based on jquery. I dont care about IE oder Chrome, just Firefox. My problem is to find if the selection is in a link for to get the value of the href attribute if is set. With click the node of the link is found, with double click always the body. It is in designMode. My event-handler for click and dblclick. The vars current_selection, current_node, iframe and container are global. selection_handler:function() { current_selection = iframe.getSelection(); current_node = current_selection.anchorNode; if(current_node.nodeName == "#text") { current_node = current_node.parentNode; } $('#log').text(current_node.nodeName); }, The log shows mit for example 'body', when I click in unformated text. When I add a link with execCommand('createLink',...) the log shows 'A'. That works. When I mark the linked word with 2 click from start to end, the log shows 'A'. But with double click I always get 'body'. So I can't get the href attribute. The handler is defined in the init: init:function(options) { ... iframe = $('#wysiwyg-'+container.attr('id'))[0].contentWindow; iframe.addEventListener('dblclick',methods.selection_handler,false); iframe.addEventListener('click',methods.selection_handler,false); ... } Has somebody an idea what is wrong?

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  • Strange compiler complaint when using similar code

    - by Jason
    For a project, I have to ask the user for a file name, and I'm reading it in character by character using getchar. From the main, I call the function char *coursename= introPrint(); //start off to print the usage directions and get the first bit of input. That function is defined as char *introPrint(){ int size= 20; int c; int length=0; char buffer[size]; //instructions printout, cut for brevity //get coursename from user and return it while ( (c=getchar()) != EOF && (c != '\n') ){ buffer[length++]= c; if (length==size-1) break; } buffer[length]=0; return buffer; } This is basically identical code I wrote to ask the user for input, replace the character echo with asterisks, then print out the results. Here, though, I'm getting a function returns address of local variable warning for the return statement. So why am I getting no warnings from the other program, but trigger one for this code?

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  • R optimization: How can I avoid a for loop in this situation?

    - by chrisamiller
    I'm trying to do a simple genomic track intersection in R, and running into major performance problems, probably related to my use of for loops. In this situation, I have pre-defined windows at intervals of 100bp and I'm trying to calculate how much of each window is covered by the annotations in mylist. Graphically, it looks something like this: 0 100 200 300 400 500 600 windows: |-----|-----|-----|-----|-----|-----| mylist: |-| |-----------| So I wrote some code to do just that, but it's fairly slow and has become a bottleneck in my code: ##window for each 100-bp segment windows <- numeric(6) ##second track mylist = vector("list") mylist[[1]] = c(1,20) mylist[[2]] = c(120,320) ##do the intersection for(i in 1:length(mylist)){ st <- floor(mylist[[i]][1]/100)+1 sp <- floor(mylist[[i]][2]/100)+1 for(j in st:sp){ b <- max((j-1)*100, mylist[[i]][1]) e <- min(j*100, mylist[[i]][2]) windows[j] <- windows[j] + e - b + 1 } } print(windows) [1] 20 81 101 21 0 0 Naturally, this is being used on data sets that are much larger than the example I provide here. Through some profiling, I can see that the bottleneck is in the for loops, but my clumsy attempt to vectorize it using *apply functions resulted in code that runs an order of magnitude more slowly. I suppose I could write something in C, but I'd like to avoid that if possible. Can anyone suggest another approach that will speed this calculation up?

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  • Once an HTML document has a manifest (cache.manifest), how can you remove it?

    - by Michael F
    It seems that once you have a manifest entry, a la: <html manifest="cache.manifest"> Then that page (the master entry in the cache) will always be cached (at least by Safari) until the user does something to remove the cache, even if you later remove the manifest attribute from the html tag and update the manifest (by changing something within it), forcing the master entry to be reloaded along with everything else. In other words, if you have: index.html (with manifest defined) file1.js (referenced in manifest) file2.js (referenced in manifest) cache.manifest (lists the two js files) -- removing the manifest entry from index.html and modifying the manifest (so it gets expired by the browser and all content reloaded) will not stop this page from behaving as if it's still fully cached. If you view source on index.html you won't see the manifest listed anymore, but the browser will still request only the cache.manifest file, and unless that file's content is changed, no other changes to any files will be shown to the user. It seems like a pretty glaring bug, and it's present on iOS as well as Mac versions of Safari. Has anyone found a way of resetting the page and getting rid of the cache without requiring user intervention?

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  • Java: refactoring static constants

    - by akf
    We are in the process of refactoring some code. There is a feature that we have developed in one project that we would like to now use in other projects. We are extracting the foundation of this feature and making it a full-fledged project which can then be imported by its current project and others. This effort has been relatively straight-forward but we have one headache. When the framework in question was originally developed, we chose to keep a variety of constant values defined as static fields in a single class. Over time this list of static members grew. The class is used in very many places in our code. In our current refactoring, we will be elevating some of the members of this class to our new framework, but leaving others in place. Our headache is in extracting the foundation members of this class to be used in our new project, and more specifically, how we should address those extracted members in our existing code. We know that we can have our existing Constants class subclass this new project's Constants class and it would inherit all of the parent's static members. This would allow us to effect the change without touching the code that uses these members to change the class name on the static reference. However, the tight coupling inherent in this choice doesn't feel right. before: public class ConstantsA { public static final String CONSTANT1 = "constant.1"; public static final String CONSTANT2 = "constant.2"; public static final String CONSTANT3 = "constant.3"; } after: public class ConstantsA extends ConstantsB { public static final String CONSTANT1 = "constant.1"; } public class ConstantsB { public static final String CONSTANT2 = "constant.2"; public static final String CONSTANT3 = "constant.3"; } In our existing code branch, all of the above would be accessible in this manner: ConstantsA.CONSTANT2 I would like to solicit arguments about whether this is 'acceptable' and/or what the best practices are.

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  • python interactive mode module import issue

    - by Jeff
    I believe I have what would be called a scope issue, perhaps name space. Not too sure I'm new to python. I'm trying to make a module that will search through a list using regular expressions. I'm sure there is a better way of doing it but this error that I'm getting is bugging me and I want to understand why. here's my code: class relist(list): def __init__(self, l): list.__init__(self, l) def __getitem__(self, rexp): r = re.compile(rexp) res = filter(r.match, self) return res if __name__ == '__main__': import re listl = [x+y for x in 'test string' for y in 'another string for testing'] print(listl) test = relist(listl) print('----------------------------------') print(test['[s.]']) When I run this code through the command line it works the way I expect it to; however when I run it through python interactive mode I get the error >>> test['[s.]'] Traceback (most recent call last): File "<stdin>", line 1, in <module> File "relist.py", line 8, in __getitem__ r = re.compile(rexp) NameError: global name 're' is not defined While in the interactive mode I do import re and I am able to use the re functions, but for some reason when I'm trying to execute the module it doesn't work. Do I need to import re into the scope of the class? I wouldn't think so because doesn't python search through other scopes if it's not found in the current one? I appreciate your help, and if there is a better way of doing this search I would be interested in knowing. Thanks

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  • Storing Result set into an array

    - by OVERTONE
    i know this should be simpel and im probably staring straight at the problem but once again im stuck and need the help of the code gurus. im trying too take one row from a column in jdbc, and put them in an array. i do this as follows: public void fillContactList() { createConnection(); try { Statement stmt = conn.createStatement(); ResultSet namesList = stmt.executeQuery("SELECT name FROM Users"); try { while (namesList.next()) { contactListNames[1] = namesList.getString(1); System.out.println("" + contactListNames[1]); } } catch(SQLException q) { } conn.commit(); stmt.close(); conn.close(); } catch(SQLException e) { } creatConnection is an already defined method that does what it obviously does. i creat my result set while theres another one, i store the string of that column into an array. then print it out for good measure. too make sure its there. the problem is that its storing the entire column into contactListNames[1] i wanted to make it store column1 row 1 into [1] then column 1 row 2 into [2] i know i could do this with a loop. but i dont know too take only one row at a time from a single column. any ideas? p.s ive read the api, i jsut cant see anything that fits.

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  • Creating a clickable progress bar

    - by Cory
    What I'm essentially building is a webkit based controller that communicates with a program called Ecoute.app. The controller has a progressbar that indicates the progress made through the currently playing song, but I want to make this bar's position adjustable with a click. function barClick() { var progress = Ecoute.playerPosition(); var width = 142.5; var percentElapsed = progress / length; var position = width * percentElapsed; Ecoute.setPlayerPosition(position); } Is what I have, with Ecoute.playerPosition() returning the player's current position. Width has previously been defined as a dynamic value at var width = 142.5 / length * progress + 1.63; With length being the current track length and progress being the player's position. This has been able to dynamically stretch a progression overlay image to indicate the position of the track via the desktop controller. However, the max width used in the second function does not appear to allow the first function to work properly. Any help possibly determining the correct value or approach would be hugely appreciated.

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  • When is a bool not a bool (compiler warning C4800)

    - by omatai
    Consider this being compiled in MS Visual Studio 2005 (and probably others): CPoint point1( 1, 2 ); CPoint point2( 3, 4 ); const bool point1And2Identical( point1 == point2 ); // C4800 warning const bool point1And2TheSame( ( point1 == point2 ) == TRUE ); // no warning What the...? Is the MSVC compiler brain-dead? As far as I can tell, TRUE is #defined as 1, without any type information. So by what magic is there any difference between these two lines? Surely the type of the expression inside the brackets is the same in both cases? [This part of the question now satisfactorily answered in the comments just below] Personally, I think that avoiding the warning by using the == TRUE option is ugly (though less ugly than the != 0 alternative, despite being more strictly correct), and it is better to use #pragma warning( disable:4800 ) to imply "my code is good, the compiler is an ass". Agree? Note - I have seen all manner of discussion on C4800 talking about assigning ints to bools, or casting a burger combo with large fries (hold the onions) to a bool, and wondering why there are strange results. I can't find a clear answer on what seems like a much simpler question... that might just shine line on C4800 in general.

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  • How to use accessors within the same class in Objective C?

    - by Azeworai
    Hi, I have a few properties defined in my header file like so @property (assign) bool connectivity_N; @property (assign) bool isConnected_N; In my implementation file I have an init and the synthesized properties like so @implementation Map @synthesize connectivity_N; @synthesize isConnected_N; a init to set the initial values like so -(id) init { if( (self=[super init]) ) { //initialise default properties self.connectivity_N=NO; self.isConnected_N=NO; } return self; } I'm running into an error that states Error: accessing unknown 'connectivity_N' class method. In this public method within the class +(bool) isConnectable:(directions) theDirection{ bool isTheDirectionConnectable= NO; switch (theDirection) { case north: isTheDirectionConnectable= self.connectivity_N; break; I'm not sure why is this so as I'm trying to grab the value of the property. According to the apple developer documentation "The default names for the getter and setter methods associated with a property are propertyName and setPropertyName: respectively—for example, given a property “foo”, the accessors would be foo and setFoo:" That has given me a clue that I've done something wrong here, I'm fairly new to objective C so would appreciate anyone who spends the time to explain this to me. Thanks!

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  • In CakePHP, how do I create a form to list models withing a date range?

    - by anonymous coward
    I have a very simple model that includes the auto-filled field much like 'created'. (DateTime format). I'd like to use the Form helpers if possible, to validate the date fields and whatnot. I'd like a simple form with a "Begin Date" (YMD, 12 hours), and an "End Date" (same format). There is already a controller action set up as follows: function view_between($start_date = null, $end_date = null) { // ... stuff that works correctly when the URL is manually entered. } Have I defined the controller wrong, or how can I pass these values into that function? The reason I'm stuck is because I tried adding a $form->input('my_datetime_field' ...) twice, but obviously the name/id were the same on the respective elements. I have also tried using $form->dateTime(...) with similar results. I'm not sure how to uniquely identify a Begin and End date selection, when it should interact with a single field. Am I going about this wrong? A kind shove in the right direction should suffice.

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  • Django throws 404 at generic views

    - by x0rg
    I'm trying to get the generic views for a date-based archive working in django. I defined the urls as described in a tutorial, but django returns a 404 error whenever I want to access an url with a variable (such as month or year) in it. It don't even produces a TemplateDoesNotExist-execption. Normal urls without variables work fine. Here's my urlconf: from django.conf.urls.defaults import * from zurichlive.zhl.models import Event info_dict = { 'queryset': Event.objects.all(), 'date_field': 'date', 'allow_future': 'True', } urlpatterns += patterns('django.views.generic.date_based', (r'events/(?P<year>d{4})/(?P<month>[a-z]{3})/(?P<day>w{1,2})/(?P<slug>[-w]+)/$', 'object_detail', dict(info_dict, slug_field='slug',template_name='archive/detail.html')), (r'^events/(?P<year>d{4})/(?P<month>[a-z]{3})/(?P<day>w{1,2})/(?P<slug>[-w]+)/$', 'object_detail', dict(info_dict, template_name='archive/list.html')), (r'^events/(?P<year>d{4})/(?P<month>[a-z]{3})/(?P<day>w{1,2})/$','archive_day',dict(info_dict,template_name='archive/list.html')), (r'^events/(?P<year>d{4})/(?P<month>[a-z]{3})/$','archive_month', dict(info_dict, template_name='archive/list.html')), (r'^events/(?P<year>)/$','archive_year', dict(info_dict, template_name='archive/list.html')), (r'^events/$','archive_index', dict(info_dict, template_name='archive/list.html')), ) When I access /events/2010/may/12/this-is-a-slug I should get to the detail.html template, but instead I get a 404. What am I doing wrong?

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  • fopen / fopen_s and writing to files

    - by yCalleecharan
    Hi, I'm using fopen in C to write the output to a text file. The function declaration is (where ARRAY_SIZE has been defined earlier): void create_out_file(char file_name[],long double *z1){ FILE *out; int i; if((out = fopen(file_name, "w+")) == NULL){ fprintf(stderr, "* Open error on output file %s", file_name); exit(-1); } for(i = 0; i < ARRAY_SIZE; i++) fprintf(out, "%.16Le\n", z1[i]); fclose(out); } My questions: On compilation with MVS2008 I get the warning: warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. I haven't see much information on fopen_s so that I can change my code. Any suggestions? Can one instruct fprintf to write at desired precision? If I'm using long double then I assume that my answers are good till 15 digits after the decimal point. Am I right? Thanks a lot...

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  • Cannot perform an ORDERBY against my EF4 data

    - by Jaxidian
    I have a query hitting EF4 using STEs and I'm having an issue with user-defined sorting. In debugging this, I have removed the dynamic sorting and am hard-coding it and I still have the issue. If I swap/uncomment the var results = xxx lines in GetMyBusinesses(), my results are not sorted any differently - they are always sorting it ascendingly. FYI, Name is a varchar(200) field in SQL 2008 on my Business table. private IQueryable<Business> GetMyBusinesses(MyDBContext CurrentContext) { var myBusinesses = from a in CurrentContext.A join f in CurrentContext.F on a.FID equals f.id join b in CurrentContext.Businesses on f.BID equals b.id where a.PersonID == 52 select b; var results = from r in myBusinesses orderby "Name" ascending select r; //var results = from r in results // orderby "Name" descending // select r; return results; } private PartialEntitiesList<Business> DoStuff() { var myBusinesses = GetMyBusinesses(); var myBusinessesCount = GetMyBusinesses().Count(); Results = new PartialEntitiesList<Business>(myBusinesses.Skip((PageNumber - 1)*PageSize).Take(PageSize).ToList()) {UnpartialTotalCount = myBusinessesCount}; return Results; } public class PartialEntitiesList<T> : List<T> { public PartialEntitiesList() { } public PartialEntitiesList(int capacity) : base(capacity) { } public PartialEntitiesList(IEnumerable<T> collection) : base(collection) { } public int UnpartialTotalCount { get; set; } }

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  • Using a variable in a mysql query, in a C++ MFC program.

    - by D.Gaughan
    Hi, after extensive trawling of the internet I still havent found any solution for this problem. I`m writing a small C++ app that connects to an online database and outputs the data in a listbox. I need to enable a search function using an edit box, but I cant get the query to work while using a variable. My code is: res = mysql_perform_query (conn, "select distinct artist from Artists"); //res = mysql_perform_query (conn, "select album from Artists where artist = ' ' "); while((row = mysql_fetch_row(res)) != NULL){ CString str; UpdateData(); str = ("%s\n", row[0]); UpdateData(FALSE); m_list_control.AddString(str); } the first "res = " line is working fine, but I need the second one to work. I have a member variable m_search_edit set up for the edit box, but any way I try to include it in the sql statement causes errors. eg. res = mysql_perform_query (conn, "select album from Artists where artist = '"+m_search_edit+" ' "); causes this error: error C2664: 'mysql_perform_query' : cannot convert parameter 2 from 'class CString' to 'char *' No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called" And when I convert m_search_edit to a char* it gives me a " Cannot add 2 pointers" error. Any way around this???

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  • How would I associate a "Note" class to 4+ classes without creating lookup table for each associatio

    - by Gthompson83
    Im creating a project tasklist application. I have project, section, task, issue classes, and would like to use one class to be able to add simple notes to any object instance of those classes. The task, issue tables both use a standard identity field as a primary key. The section table has a two field primary key. The project table has a single int primary key defined by the user. Is there a way to associate the note class with each of these without using a seperate lookup table for each class? I'm not so sure my original idea is a decent way to implement this. I considered the following (each variable mapping to a field n the notes table. Private _NoteId As Integer Private _ProjectId As Integer Private _SectionId As Integer Private _SectionId2 As Integer Private _TaskId As Integer Private _IssueId As Integer Private _Note As String Private _UserId As Guid Then I would be able to write seperate methods (getProjectNotes, getTaskNotes) to get notes attached to each class. I started writing this a few weeks ago but got pulled away before i could finish. When revisiting this code today my first thought "this is retarded". Thoughts on drawbacks to this design?

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  • Can't give my custom prototype cells in tableview different heights

    - by kerbelda
    I've looked around at other questions here and many other sources online and just can't find a solution. I have 3 rows and no matter what I do, they all keep the width defined in the tableview. The first one is what I want, but the second and 3rd I can't give a custom height. Below is my code: #import "DetailTableViewController.h" #import "EventDetailTableViewCell.h" #import "EventDescriptionTableViewCell.h" #import "EventMapTableViewCell.h" @interface DetailTableViewController () @end @implementation DetailTableViewController - (void)viewDidLoad { [super viewDidLoad]; } #pragma mark - Table view data source - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { // Return the number of sections. return 3; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { // Return the number of rows in the section. return 1; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { if (indexPath.section == 0) { static NSString *CellIdentifier = @"headerCell"; EventDetailTableViewCell *headerCell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; headerCell.headerImage.image = [UIImage imageNamed:@"img4.png"]; return headerCell; } else if (indexPath.section == 1) { static NSString *CellIdentifier = @"descriptionCell"; EventDescriptionTableViewCell *descriptionCell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; descriptionCell.descriptionImage.image = [UIImage imageNamed:@"img2.png"]; return descriptionCell; } else { static NSString *CellIdentifier = @"mapCell"; EventMapTableViewCell *mapCell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; return mapCell; } } #pragma mark - Helper Methods - (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section { if (section == 1) { return @" "; } else if (section == 2) { return @" "; } else { return nil; } } -(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { if (indexPath.row == 0) { return 222; } else if (indexPath.row == 1) { return 80; } else { return 100; } } @end

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  • Compile time type determination in C++

    - by dicroce
    A coworker recently showed me some code that he found online. It appears to allow compile time determination of whether a type has an "is a" relationship with another type. I think this is totally awesome, but I have to admit that I'm clueless as to how this actually works. Can anyone explain this to me? template<typename BaseT, typename DerivedT> inline bool isRelated(const DerivedT&) { DerivedT derived(); char test(const BaseT&); // sizeof(test()) == sizeof(char) char (&test(...))[2]; // sizeof(test()) == sizeof(char[2]) struct conversion { enum { exists = (sizeof(test(derived())) == sizeof(char)) }; }; return conversion::exists; } Once this function is defined, you can use it like this: #include <iostream> class base {}; class derived : public base {}; class unrelated {}; int main() { base b; derived d; unrelated u; if( isRelated<base>( b ) ) std::cout << "b is related to base" << std::endl; if( isRelated<base>( d ) ) std::cout << "d is related to base" << std::endl; if( !isRelated<base>( u ) ) std::cout << "u is not related to base" << std::endl; }

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  • Declaring an object of a conditional type with a System.Type

    - by Chapso
    I am attempting to launch a specific form depending on the selected node of a treeview on the doubleclick event. The code I need to use to launch the form is a little bulky becuase I have to ensure that the form is not disposed, and that the form is not already open, before launching a new instance. I'd like to have all of this checking happen in one place at the end of the function, which means that I have to be able to pass the right form type to the code at the end. I'm trying to do this with a System.Type, but that doesn't seem to be working. Could someone point me in the right direction, please? With TreeView.SelectedNode Dim formType As Type Select Case .Text Case "Email to VPs" formType = EmailForm.GetType() Case "Revise Replacers" formType = DedicatedReplacerForm.GetType() Case "Start Email" formType = EmailForm.GetType() End Select Dim form As formType Dim form As formType Try form = CType(.Tag, formType) If Not form.IsDisposed Then form.Activate() Exit Sub End If Catch ex As NullReferenceException 'This will error out the first time it is run as the form has not yet ' been defined. End Try form = New formType form.MdiParent = Me .Tag = form CType(TreeView.SelectedNode.Tag, Form).Show() End With

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  • Using h:outputFormat to message-format the f:selectItems of a h:selectOneRadio

    - by msharma
    I am having some trouble with using h:selectOneRadio. I have a list of objects which is being returned which needs to be displayed. I am trying something like this: <h:selectOneRadio id="selectPlan" layout="pageDirection"> <f:selectItems value="#{detailsHandler.planList}" /> </h:selectOneRadio> and planList is a List of Plans. Plan is defined as: public class Plan { protected String id; protected String partNumber; protected String shortName; protected String price; protected boolean isService; protected boolean isOption; //With all getters/setters } The text that must appear for each radio button is actually in a properties file, and I need to insert params in the text to fill out some value in the bean. For example the text in my properties file is: plan_price=The price of this plan is {0}. I was hoping to do something like this: <f:selectItems value="<h:outputFormat value="#{i18n.plan_price}"> <f:param value="#{planHandler.price}"> </h:outputFormat>" /> Usually if it's not a h:selectOneRadio component, if it's just text I use the h:outputFormat along with f:param tags to display the messages in my .property file called i18n above, and insert a param which is in the backing bean. here this does not work. Does anyone have any ideas how I can deal with this? I am being returned a list of Plans each with their own prices and the text to be displayed is held in property file. Any help much appreciated. Thanks!

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  • Retaining column state in grid panel depending on the user settings.

    - by xrx215
    Hi, I have a grid panel where I am retaining the state of the columns.It works fine for all the columns except one where i show or hide the column depending on user settings. If a checkbox is checked then i show the column in grid panel else hide it. In the column model I have defined the column as follows var colModel = new Ext.grid.ColumnModel([{ header: xppo.st('SDE_RESPONSIBILITY_ACTION1'), width: 80, sortable: true, hidden: !showColumn, hideable: !showInMenu, dataIndex: 'ResponsibilityForAction' }} In the grid panel I have given the following if (showColumn) { grid.getColumnModel().setHidden(23, false); } else { grid.getColumnModel().setHidden(23, true); } so i change the value of the checkbox column in the column header is shown (alowing the user to enable and disable in grid panel) or completely not shown in the column menu. So when the column in column menu does not exists it should no longer show that particular column in grid panel.But because I am retaining the state of the grid panel even though the column in column menu does not exists this particular column retains the state i.e it is still shown in grid panel. My question is how can we show or hide columns in grid panel like the way we do in column model.??

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