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  • Approaches to replace cursor in pure AS3 / Flare project?

    - by peteorpeter
    Hi there good lookin, I've got a pure AS3 (no Flex) project that uses Flare to display and interact with a data visualization. I just implemented some panning behavior, so you can click and drag the visualization around, and now I'd like to give the user a visual indicator that this is possible, by switching the arrow cursor with a nice grabby-looking hand icon. The user can click and drag at any time except when the mouse is over a clickable node (at which time the cursor swaps to a pointer - this behavior is already in place). So... 1) Do I need to create my own custom bitmap/sprite or is there a palette of built-in cursors I can use? (I'm not using Flex.) 2) Is there a way to simply replace the default arrow with the pan cursor project-wide, or do I need to attach the swapping to mouse events on display objects? Can I use the stage object to make this behavior apply everywhere? 3) How do I perform the swap? Do I use the Cursor object directly or do I need to get involved with the CursorManager? Any guidance, pseudo-code, or words of wisdom is greatly appreciated!

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  • How do I make JPA POJO classes + Netbeans forms play well together?

    - by Zak
    I started using netbeans to design forms to edit the instances of various classes I have made in a small app I am writing. Basically, the app starts, an initial set of objects is selected from the DB and presented in a list, then an item in the list can be selected for editing. When the editor comes up it has form fields for many of the data fields in the class. The problem I run into is that I have to create a controller that maps each of the data elements to the correct form element, and create an inordinate number of small conversion mapping lines of code to convert numbers into strings and set the correct element in a dropdown, then another inordinate amount of code to go back and update the underlying object with all the values from the form when the save button is clicked. My question is; is there a more directly way to make the editing of the form directly modify the contents of my class instance? I would like to be able to have a default mapping "controller" that I can configure, then override the getter/setter for a particular field if needed. Ideally, there would be standard field validation for things like phone numbers, integers, floats, zip codes, etc... I'm not averse to writing this myself, I would just like to see if it is already out there and use the right tool for the right job.

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  • c++ Design pattern for CoW, inherited classes, and variable shared data?

    - by krunk
    I've designed a copy-on-write base class. The class holds the default set of data needed by all children in a shared data model/CoW model. The derived classes also have data that only pertains to them, but should be CoW between other instances of that derived class. I'm looking for a clean way to implement this. If I had a base class FooInterface with shared data FooDataPrivate and a derived object FooDerived. I could create a FooDerivedDataPrivate. The underlying data structure would not effect the exposed getters/setters API, so it's not about how a user interfaces with the objects. I'm just wondering if this is a typical MO for such cases or if there's a better/cleaner way? What peeks my interest, is I see the potential of inheritance between the the private data classes. E.g. FooDerivedDataPrivate : public FooDataPrivate, but I'm not seeing a way to take advantage of that polymorphism in my derived classes. class FooDataPrivate { public: Ref ref; // atomic reference counting object int a; int b; int c; }; class FooInterface { public: // constructors and such // .... // methods are implemented to be copy on write. void setA(int val); void setB(int val); void setC(int val); // copy constructors, destructors, etc. all CoW friendly private: FooDataPrivate *data; }; class FooDerived : public FooInterface { public: FooDerived() : FooInterface() {} private: // need more shared data for FooDerived // this is the ???, how is this best done cleanly? };

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  • Why can't I roll a loop in Javascript?

    - by Carl Manaster
    I am working on a web page that uses dojo and has a number (6 in my test case, but variable in general) of project widgets on it. I'm invoking dojo.addOnLoad(init), and in my init() function I have these lines: dojo.connect(dijit.byId("project" + 0).InputNode, "onChange", function() {makeMatch(0);}); dojo.connect(dijit.byId("project" + 1).InputNode, "onChange", function() {makeMatch(1);}); dojo.connect(dijit.byId("project" + 2).InputNode, "onChange", function() {makeMatch(2);}); dojo.connect(dijit.byId("project" + 3).InputNode, "onChange", function() {makeMatch(3);}); dojo.connect(dijit.byId("project" + 4).InputNode, "onChange", function() {makeMatch(4);}); dojo.connect(dijit.byId("project" + 5).InputNode, "onChange", function() {makeMatch(5);}); and change events for my project widgets properly invoke the makeMatch function. But if I replace them with a loop: for (var i = 0; i < 6; i++) dojo.connect(dijit.byId("project" + i).InputNode, "onChange", function() {makeMatch(i);}); same makeMatch() function, same init() invocation, same everything else - just rolling my calls up into a loop - the makeMatch function is never called; the objects are not wired. What's going on, and how do I fix it? I've tried using dojo.query, but its behavior is the same as the for loop case.

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  • NSTableView selection & highlights

    - by Christian
    I have a NSTableView as a very central part of my Application and want it to integrate more with the rest of it. It has only one column (it's a list) and I draw all Cells (normal NSTextFieldCells) myself. The first problem is the highlighting. I draw the highlight myself and want to get rid of the blue background. I now fill the whole cell with the original background color to hide the blue background, but this looks bad when dragging the cell around. I tried overriding highlight:withFrame:inView: and highlightColorWithFrame:inView: of NSCell but nothing happened. How can I disable automatic highlighting? I also want all rows/cells to be deselected when I click somewhere outside my NSTableView. Since the background / highlight of the selected cell turns gray there must be an event for this, but I can't find it. I let my cells expand on a double click and may need to undo this. So getting rid of the gray highlight is not enough. EDIT: I add a subview to the NSTableView when a cell gets double clicked and then resignFirstResponder of the NSTableView gets called. I tried this: - (BOOL)resignFirstResponder { if (![[self subviews] containsObject:[[self window] firstResponder]]) { [self deselectAll:self]; ... } return YES; } Besides that it's not working I would need to implement this method for all objects in the view hierarchy. Is there an other solution to find out when the first responder leaves a certain view hierarchy?

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  • JQuery checkbox state is updated differently between group click() and $.each(obj.click())

    - by teerapap
    The code below doesn't work in the same behavior. The sequence of click event and calling foo() is different. I want to know why they behave different sequence between call click() and iterate the objects before call click() on each. <script type="text/javascript"> function foo(obj){ alert(obj.id+" ->"+obj.checked); } function clickAll(val){ if (val) { $(":checkbox").click(); } else { $(":checkbox").each(function(i,obj){ obj.click(); }); } } </script> </head> <body> <input type="checkbox" id="check1" onclick="foo(this)" /> a <input type="checkbox" id="check2" onclick="foo(this)" /> b <input type="checkbox" id="check3" onclick="foo(this)" /> c <input type="button" onclick="clickAll(true)" value="click all" /> <input type="button" onclick="clickAll(false)" value="click all each" /> </body>

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  • Using Subsonic 3.0 Advanced Templates

    - by umit
    Hi all, I've been trying to use Subsonic Advanced Templates in a project for a while but most of the time I find myself writing a Stored Procedure as I can't find a proper way of doing it in code. Subsonic created corresponding objects for my DB tables and for foreign keys it created IQueryable fields inside each object. These fields are not loaded by default and a new SQL query is executed when you access them. 1- Is there a way to get all data in one query (deep load)? Also these fields can not be assigned. So when I want to create an object in a maintenance page, I can't put all the data into this object before saving it in DB: Post post = new Post(); //get photos for this post IList<PostPhoto> postPhotos = GetPostPhotos(); post.PostPhotos = postPhotos; 2- Is it possible to have one Post object with all fields set from user input? Think of the Post object above and assume I've successfully assigned its fields. Now I need to save it to the DB. 3- Is using BatchQuery the only way to do it in one query? If I have 4 photos in PostPhotos field; 2 of them previously saved and 2 of them new, can I use the Update method to handle both the adding and updating of these photos? Any ideas or links are appreciated. Cheers...

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  • Reduce function calls

    - by Curious2learn
    Hello, I profiled my python program and found that the following function was taking too long to run. Perhaps, I can use a different algorithm and make it run faster. However, I have read that I can also possibly increase the speed by reducing function calls, especially when it gets called repeatedly within a loop. I am a python newbie and would like to learn how to do this and see how much faster it can get. Currently, the function is: def potentialActualBuyers(setOfPeople,theCar,price): count=0 for person in setOfPeople: if person.getUtility(theCar) >= price and person.periodCarPurchased==None: count += 1 return count where setOfPeople is a list of person objects. I tried the following: def potentialActualBuyers(setOfPeople,theCar,price): count=0 Utility=person.getUtility for person in setOfPeople: if Utility(theCar) >= price and person.periodCarPurchased==None: count += 1 return count This, however, gives me an error saying local variable 'person' referenced before assignment Any suggestions, how I can reduce function calls or any other changes that can make the code faster. Again, I am a python newbie and even though I may possibly be able to use a better algorithm, it is still worthwhile learning the answer to the above question. Thanks very much.

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  • How do you convert a parent-child (adjacency) table to a nested set using PHP and MySQL?

    - by mrbinky3000
    I've spent the last few hours trying to find the solution to this question online. I've found plenty of examples on how to convert from nested set to adjacency... but few that go the other way around. The examples I have found either don't work or use MySQL procedures. Unfortunately, I can't use procedures for this project. I need a pure PHP solution. I have a table that uses the adjacency model below: id parent_id category 1 0 ROOT_NODE 2 1 Books 3 1 CD's 4 1 Magazines 5 2 Books/Hardcover 6 2 Books/Large Format 7 4 Magazines/Vintage And I would like to convert it to a Nested Set table below: id left right category 1 1 14 Root Node 2 2 7 Books 3 3 4 Books/Hardcover 4 5 6 Books/Large Format 5 8 9 CD's 6 10 13 Magazines 7 11 12 Magazines/Vintage Here is an image of what I need: I have a function, based on the pseudo code from this forum post (http://www.sitepoint.com/forums/showthread.php?t=320444) but it doesn't work. I get multiple rows that have the same value for left. This should not happen. <?php /** -- -- Table structure for table `adjacent_table` -- CREATE TABLE IF NOT EXISTS `adjacent_table` ( `id` int(11) NOT NULL AUTO_INCREMENT, `father_id` int(11) DEFAULT NULL, `category` varchar(128) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; -- -- Dumping data for table `adjacent_table` -- INSERT INTO `adjacent_table` (`id`, `father_id`, `category`) VALUES (1, 0, 'ROOT'), (2, 1, 'Books'), (3, 1, 'CD''s'), (4, 1, 'Magazines'), (5, 2, 'Hard Cover'), (6, 2, 'Large Format'), (7, 4, 'Vintage'); -- -- Table structure for table `nested_table` -- CREATE TABLE IF NOT EXISTS `nested_table` ( `id` int(11) NOT NULL AUTO_INCREMENT, `lft` int(11) DEFAULT NULL, `rgt` int(11) DEFAULT NULL, `category` varchar(128) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ; */ mysql_connect('localhost','USER','PASSWORD') or die(mysql_error()); mysql_select_db('DATABASE') or die(mysql_error()); adjacent_to_nested(0); /** * adjacent_to_nested * * Reads a "adjacent model" table and converts it to a "Nested Set" table. * @param integer $i_id Should be the id of the "root node" in the adjacent table; * @param integer $i_left Should only be used on recursive calls. Holds the current value for lft */ function adjacent_to_nested($i_id, $i_left = 0) { // the right value of this node is the left value + 1 $i_right = $i_left + 1; // get all children of this node $a_children = get_source_children($i_id); foreach ($a_children as $a) { // recursive execution of this function for each child of this node // $i_right is the current right value, which is incremented by the // import_from_dc_link_category method $i_right = adjacent_to_nested($a['id'], $i_right); // insert stuff into the our new "Nested Sets" table $s_query = " INSERT INTO `nested_table` (`id`, `lft`, `rgt`, `category`) VALUES( NULL, '".$i_left."', '".$i_right."', '".mysql_real_escape_string($a['category'])."' ) "; if (!mysql_query($s_query)) { echo "<pre>$s_query</pre>\n"; throw new Exception(mysql_error()); } echo "<p>$s_query</p>\n"; // get the newly created row id $i_new_nested_id = mysql_insert_id(); } return $i_right + 1; } /** * get_source_children * * Examines the "adjacent" table and finds all the immediate children of a node * @param integer $i_id The unique id for a node in the adjacent_table table * @return array Returns an array of results or an empty array if no results. */ function get_source_children($i_id) { $a_return = array(); $s_query = "SELECT * FROM `adjacent_table` WHERE `father_id` = '".$i_id."'"; if (!$i_result = mysql_query($s_query)) { echo "<pre>$s_query</pre>\n"; throw new Exception(mysql_error()); } if (mysql_num_rows($i_result) > 0) { while($a = mysql_fetch_assoc($i_result)) { $a_return[] = $a; } } return $a_return; } ?> This is the output of the above script. INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '2', '5', 'Hard Cover' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '2', '7', 'Large Format' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '1', '8', 'Books' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '1', '10', 'CD\'s' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '10', '13', 'Vintage' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '1', '14', 'Magazines' ) INSERT INTO nested_table (id, lft, rgt, category) VALUES( NULL, '0', '15', 'ROOT' ) As you can see, there are multiple rows sharing the lft value of "1" same goes for "2" In a nested-set, the values for left and right must be unique. Here is an example of how to manually number the left and right ID's in a nested set: UPDATE - PROBLEM SOLVED First off, I had mistakenly believed that the source table (the one in adjacent-lists format) needed to be altered to include a source node. This is not the case. Secondly, I found a cached page on BING (of all places) with a class that does the trick. I've altered it for PHP5 and converted the original author's mysql related bits to basic PHP. He was using some DB class. You can convert them to your own database abstraction class later if you want. Obviously, if your "source table" has other columns that you want to move to the nested set table, you will have to adjust the write method in the class below. Hopefully this will save someone else from the same problems in the future. <?php /** -- -- Table structure for table `adjacent_table` -- DROP TABLE IF EXISTS `adjacent_table`; CREATE TABLE IF NOT EXISTS `adjacent_table` ( `id` int(11) NOT NULL AUTO_INCREMENT, `father_id` int(11) DEFAULT NULL, `category` varchar(128) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; -- -- Dumping data for table `adjacent_table` -- INSERT INTO `adjacent_table` (`id`, `father_id`, `category`) VALUES (1, 0, 'Books'), (2, 0, 'CD''s'), (3, 0, 'Magazines'), (4, 1, 'Hard Cover'), (5, 1, 'Large Format'), (6, 3, 'Vintage'); -- -- Table structure for table `nested_table` -- DROP TABLE IF EXISTS `nested_table`; CREATE TABLE IF NOT EXISTS `nested_table` ( `lft` int(11) NOT NULL DEFAULT '0', `rgt` int(11) DEFAULT NULL, `id` int(11) DEFAULT NULL, `category` varchar(128) DEFAULT NULL, PRIMARY KEY (`lft`), UNIQUE KEY `id` (`id`), UNIQUE KEY `rgt` (`rgt`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; */ /** * @class tree_transformer * @author Paul Houle, Matthew Toledo * @created 2008-11-04 * @url http://gen5.info/q/2008/11/04/nested-sets-php-verb-objects-and-noun-objects/ */ class tree_transformer { private $i_count; private $a_link; public function __construct($a_link) { if(!is_array($a_link)) throw new Exception("First parameter should be an array. Instead, it was type '".gettype($a_link)."'"); $this->i_count = 1; $this->a_link= $a_link; } public function traverse($i_id) { $i_lft = $this->i_count; $this->i_count++; $a_kid = $this->get_children($i_id); if ($a_kid) { foreach($a_kid as $a_child) { $this->traverse($a_child); } } $i_rgt=$this->i_count; $this->i_count++; $this->write($i_lft,$i_rgt,$i_id); } private function get_children($i_id) { return $this->a_link[$i_id]; } private function write($i_lft,$i_rgt,$i_id) { // fetch the source column $s_query = "SELECT * FROM `adjacent_table` WHERE `id` = '".$i_id."'"; if (!$i_result = mysql_query($s_query)) { echo "<pre>$s_query</pre>\n"; throw new Exception(mysql_error()); } $a_source = array(); if (mysql_num_rows($i_result)) { $a_source = mysql_fetch_assoc($i_result); } // root node? label it unless already labeled in source table if (1 == $i_lft && empty($a_source['category'])) { $a_source['category'] = 'ROOT'; } // insert into the new nested tree table // use mysql_real_escape_string because one value "CD's" has a single ' $s_query = " INSERT INTO `nested_table` (`id`,`lft`,`rgt`,`category`) VALUES ( '".$i_id."', '".$i_lft."', '".$i_rgt."', '".mysql_real_escape_string($a_source['category'])."' ) "; if (!$i_result = mysql_query($s_query)) { echo "<pre>$s_query</pre>\n"; throw new Exception(mysql_error()); } else { // success: provide feedback echo "<p>$s_query</p>\n"; } } } mysql_connect('localhost','USER','PASSWORD') or die(mysql_error()); mysql_select_db('DATABASE') or die(mysql_error()); // build a complete copy of the adjacency table in ram $s_query = "SELECT `id`,`father_id` FROM `adjacent_table`"; $i_result = mysql_query($s_query); $a_rows = array(); while ($a_rows[] = mysql_fetch_assoc($i_result)); $a_link = array(); foreach($a_rows as $a_row) { $i_father_id = $a_row['father_id']; $i_child_id = $a_row['id']; if (!array_key_exists($i_father_id,$a_link)) { $a_link[$i_father_id]=array(); } $a_link[$i_father_id][]=$i_child_id; } $o_tree_transformer = new tree_transformer($a_link); $o_tree_transformer->traverse(0); ?>

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  • The perfect web UI framework (with Microsoft stack?) - architecture question?

    - by Igorek
    I'm looking for suggestions for the following issue, and I realize there is really not going to be a perfect answer to my question: I have a UI built in WinForms.NET (v4.0 framework) with WCF back-end and EF4 model objects, that I am looking to port to the web. UI is not huge and is not super complex and is structured well. But it is not a super simple system either. I am looking to pick a technology stack for the web-frontend that will target desktop & partially mobile platforms, provide a good development platform to build on, and facilitate code reuse across UI and back-end tiers... I would rather avoid: custom coding of UI-centric scripts, because they are hard to debug, non-compiled, usually a maintenance nightmare, almost always start to contain business logic, and duplicate some of the logic that back-end tiers have (especially validation) custom-coding for Desktop Web and Mobile Web UI's separately (although I realize that mobile web UI will likely contain fewer of data-entry screens and more reporting screens) non-.NET technology stacks I would love to: target the reporting capabilities of the system toward mobile web browsers not have to write a single line of script (javascript, jquery, etc.) utilize a good collection of controls that produces an elegant UI use .NET for everything The way I see it right now, I need to re-write this app in Silverlight, utilize a 3rd party UI framework like Telerik, and re-do the reports UI again for mobile platforms separately. However, I'm rather concerned about the shelf-life of Silverlight and the needed to deploy a different architecture to deal with mobile platform. Is there an ASP.NET/MVC/Ajax architecture/framework/library that would allow me to get at the power of .NET and without painful (imho) client-side scripting, while providing a decent user experience Thank you

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  • problem adding object to hashtable

    - by daemonkid
    I am trying to call a class method dynamically depending on a condition. This is how I am doing it I have three classes implement a single interface interface IReadFile { string DoStuff(); } The three classes A,B,C implement the interface above. I am trying to add them to a hashtable with the code below _HashT.Add("a", new classA()); _HashT.Add("b", new classB()); _HashT.Add("c", new classC()); This compiles fine, but gives a runtime error.{Object reference not set to an instance of an object.} I was planning to return the correct class to the interface type depending on a parameter that matches the key value. say if I send in a. ClassA is returned to the interface type and the method is called. IReadFile Obj = (IReadFile )_HashT["a"].GetType(); obj.DoStuff(); How do I correct the part above where the objects need to be added to the hashtable? Or do I need to use a different approach? All the classes are in the same assembly and namespace. Thanks for your time.

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  • How do I declare "Member Fields" in Java?

    - by Bub
    This question probably reveals my total lack of knowledge in Java. But let me first show you what I thought was the correct way to declare a "member field": public class NoteEdit extends Activity { private Object mTitleText; private Object mBodyText; I'm following a google's notepad tutorial for android (here) and they simply said: "Note that mTitleText and mBodyText are member fields (you need to declare them at the top of the class definition)." I thought I got it and then realized that this little snippet of code wasn't working. if (title != null) { mTitleText.setText(title); } if (body != null) { mBodyText.setText(body); } So either I didn't set the "member fields" correctly which I thought all that was needed was to declare them private Objects at the top of the NoteEdit class or I'm missing something else. Thanks in advance for any help.UPDATE I was asked to show where these fields were being intialized here is another code snippet hope that it's helpful... @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.note_edit); Long mRowId; mTitleText = (EditText) findViewById(R.id.title); mBodyText = (EditText) findViewById(R.id.body);

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  • Can you open a form or window in an Outlook Addin (VSTO)

    - by dontpanic
    Hi, I am new to VSTO programming. I have created a basic addin for Outlook 2007 that monitors a folder containing XML text files which it opens and then sends them as an email, then deletes them. this all works fine. I want the user to be able to configure certain settings for the way the addin/program will operate, such as the folder that it will monitor, and other things. The logical way to do this is to create a menu item in the addin (which I have also done) that opens a windows form (or XAML window) that allows them to enter the parameters. In my addin I added a new item Windows Form, which worked, and the designer opened. However, in my addin code I cannot open the form. The Show() method normally associated with form objects is not available. Is this simply something you cannot do, or am I just doing it the wrong way? I have read about Outlook form regions, but these seemed to be attached to outlook items such as a new email, task, appointment etc... there doesnt seem to be a way to create a form region that can be opened in the main window of Outlook. Ideally, I would like to go with my original method of opening a new window from a menu item, but if this isnt possible I would like to hear other solutions. Thanks, Will.

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  • Django - foreignkey problem

    - by realshadow
    Hey, Imagine you have this model: class Category(models.Model): node_id = models.IntegerField(primary_key = True) type_id = models.IntegerField(max_length = 20) parent_id = models.IntegerField(max_length = 20) sort_order = models.IntegerField(max_length = 20) name = models.CharField(max_length = 45) lft = models.IntegerField(max_length = 20) rgt = models.IntegerField(max_length = 20) depth = models.IntegerField(max_length = 20) added_on = models.DateTimeField(auto_now = True) updated_on = models.DateTimeField(auto_now = True) status = models.IntegerField(max_length = 20) node = models.ForeignKey(Category_info, verbose_name = 'Category_info', to_field = 'node_id' The important part is the foreignkey. When I try: Category.objects.filter(type_id = type_g.type_id, parent_id = offset, status = 1) I get an error that get returned more than category, which is fine, because it is supposed to return more than one. But I want to filter the results trough another field, which would be type id (from the second Model) Here it is: class Category_info(models.Model): objtree_label_id = models.AutoField(primary_key = True) node_id = models.IntegerField(unique = True) language_id = models.IntegerField() label = models.CharField(max_length = 255) type_id = models.IntegerField() The type_id can be any number from 1 - 5. I am desparately trying to get only one result where the type_id would be number 1. Here is what I want in sql: SELECT n.*, l.* FROM objtree_nodes n JOIN objtree_labels l ON (n.node_id = l.node_id) WHERE n.type_id = 15 AND n.parent_id = 50 AND l.type_id = 1 Any help is GREATLY appreciated. Regards

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  • Few Basic Questions in Overriding

    - by Dahlia
    I have few problems with my basic and would be thankful if someone can clear this. What does it mean when I say base *b = new derived; Why would one go for this? We very well separately can create objects for class base and class derived and then call the functions accordingly. I know that this base *b = new derived; is called as Object Slicing but why and when would one go for this? I know why it is not advisable to convert the base class object to derived class object (because base class is not aware of the derived class members and methods). I even read in other StackOverflow threads that if this is gonna be the case then we have to change/re-visit our design. I understand all that, however, I am just curious, Is there any way to do this? class base { public: void f(){cout << "In Base";} }; class derived:public base { public: void f(){cout << "In Derived";} }; int _tmain(int argc, _TCHAR* argv[]) { base b1, b2; derived d1, d2; b2 = d1; d2 = reinterpret_cast<derived*>(b1); //gives error C2440 b1.f(); // Prints In Base d1.f(); // Prints In Derived b2.f(); // Prints In Base d1.base::f(); //Prints In Base d2.f(); getch(); return 0; } In case of my above example, is there any way I could call the base class f() using derived class object? I used d1.base()::f() I just want to know if there any way without using scope resolution operator? Thanks a lot for your time in helping me out!

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  • Components don't show in custom JPanel/JComponent

    - by Bart van Heukelom
    I've created a custom swing component. I can see it (the grid from the paint method is drawn), but the buttons that are added (verified by println) aren't shown. What am I doing wrong? Background information: I'm trying to build a tree of visible objects like the Flash/AS3 display list. public class MapPanel extends JComponent { // or extends JPanel, same effect private static final long serialVersionUID = 4844990579260312742L; public MapPanel(ShapeMap map) { setBackground(Color.LIGHT_GRAY); setPreferredSize(new Dimension(1000,1000)); setLayout(null); for (Layer l : map.getLayers()) { // LayerView layerView = new LayerView(l); // add(layerView); System.out.println(l); JButton test = new JButton(l.getName()); add(test); validate(); } } @Override protected void paintComponent(Graphics g) { // necessary? super.paintComponent(g); // background g.setColor(getBackground()); g.fillRect(0, 0, getWidth(), getHeight()); // grid g.setColor(Color.GRAY); for (double x = 0; x < getWidth(); x += 10) { g.drawLine((int)x, 0, (int)x, getHeight()); } for (double y = 0; y < getHeight(); y += 10) { g.drawLine(0, (int)y, getWidth(), (int)y); } } }

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  • JPA 2.0 Provider Hibernate

    - by Rooh
    I have very strange problem we are using jpa 2.0 with hibernate annotations based Database generated through JPA DDL is true and MySQL as Database; i will provide some reference classes and then my porblem. @MappedSuperclass public abstract class Common implements serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; @ManyToOne @JoinColumn private Address address; //with all getter and setters //as well equal and hashCode } @Entity public class Parent extends Common{ private String name; @OneToMany(cascade = {CascadeType.MERGE,CascadeType.PERSIST}, mappedBy = "parent") private List<Child> child; //setters and rest of class } @Entity public class Child extends Common{ //some properties with getter/setters } @Entity public class Address implements Serializable{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "id", updatable = false) private Long id; private String street; //rest of class with get/setter } as in code you can see that parents and child classes extends Common class so both have address property and id , the problem occurs when change the address refference in parent class it reflect same change in all child objects in list and if change address refference in child class then on merge it will change address refference of parent as well i am not able to figure out is it is problem of jpa or hibernate

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  • How to get a template tag to auto-check a checkbox in Django

    - by Daniel Quinn
    I'm using a ModelForm class to generate a bunch of checkboxes for a ManyToManyField but I've run into one problem: while the default behaviour automatically checks the appropriate boxes (when I'm editing an object), I can't figure out how to get that information in my own custom templatetag. Here's what I've got in my model: ... from django.forms import CheckboxSelectMultiple, ModelMultipleChoiceField interests = ModelMultipleChoiceField(widget=CheckboxSelectMultiple(), queryset=Interest.objects.all(), required=False) ... And here's my templatetag: @register.filter def alignboxes(boxes, cls): """ Details on how this works can be found here: http://docs.djangoproject.com/en/1.1/howto/custom-template-tags/ """ r = "" i = 0 for box in boxes.field.choices.queryset: r += "<label for=\"id_%s_%d\" class=\"%s\"><input type=\"checkbox\" name=\"%s\" value=\"%s\" id=\"id_%s_%d\" /> %s</label>\n" % ( boxes.name, i, cls, boxes.name, box.id, boxes.name, i, box.name ) i = i + 1 return mark_safe(r) The thing is, I'm only doing this so I can wrap some simpler markup around these boxes, so if someone knows how to make that happen in an easier way, I'm all ears. I'd be happy with knowing a way to access whether or not a box should be checked though.

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  • Conditional column values in NSTableView?

    - by velocityb0y
    I have an NSTableView that binds via an NSArrayController to an NSMutableArray. What's in the array are derived classes; the first few columns of the table are bound to properties that exist on the base class. That all works fine. Where I'm running into problem is a column that should only be populated if the row maps to one specific subclass. The property that column is meant to display only exists in that subclass, since it makes no sense in terms of the base class. The user will know, from the first two columns, why the third column's cell is populated/editable or not. The binding on the third column's value is on arrangedObjects, with a model path of something like "foo.name" where foo is the property on the subclass. However, this doesn't work, as the other subclasses in the hierarchy are not key-value compliant for foo. It seems like my only choice is to have foo be a property on the base class so everybody responds to it, but this clutters up the interfaces of the model objects. Has anyone come up with a clean design for this situation? It can't be uncommon (I'm a relative newcomer to Cocoa and I'm just learning the ins and outs of bindings.)

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  • Design: How to declare a specialized memory handler class

    - by Michael Dorgan
    On an embedded type system, I have created a Small Object Allocator that piggy backs on top of a standard memory allocation system. This allocator is a Boost::simple_segregated_storage< class and it does exactly what I need - O(1) alloc/dealloc time on small objects at the cost of a touch of internal fragmentation. My question is how best to declare it. Right now, it's scope static declared in our mem code module, which is probably fine, but it feels a bit exposed there and is also now linked to that module forever. Normally, I declare it as a monostate or a singleton, but this uses the dynamic memory allocator (where this is located.) Furthermore, our dynamic memory allocator is being initialized and used before static object initialization occurs on our system (as again, the memory manager is pretty much the most fundamental component of an engine.) To get around this catch 22, I added an extra 'if the small memory allocator exists' to see if the small object allocator exists yet. That if that now must be run on every small object allocation. In the scheme of things, this is nearly negligable, but it still bothers me. So the question is, is there a better way to declare this portion of the memory manager that helps decouple it from the memory module and perhaps not costing that extra isinitialized() if statement? If this method uses dynamic memory, please explain how to get around lack of initialization of the small object portion of the manager.

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  • Error when loading YAML config files in Rails

    - by ZelluX
    I am configuring Rails with MongoDB, and find a strange problem when paring config/mongo.yml file. config/mongo.yml is generated by executing script/rails generate mongo_mapper:config, and it looks like following: defaults: &defaults host: 127.0.0.1 port: 27017 development: <<: *defaults database: tc_web_development test: <<: *defaults database: tc_web_test From the config file we can see the objects development and test should both have a database field. But when it is parsed and loaded in config/initializers/mongo.db, config = YAML::load(File.read(Rails.root.join('config/mongo.yml'))) puts config.inspect MongoMapper.setup(config, Rails.env) the strange thing comes: the output of puts config.inspect is {"defaults"=>{"host"=>"127.0.0.1", "port"=>27017}, "development"=>{"host"=>"127.0.0.1", "port"=>27017}, "test"=>{"host"=>"127.0.0.1", "port"=>27017}} which does not contain database attribute. But when I execute the same statements in a plain ruby console, instead of using rails console, mongo.yml is parsed in a right way. {"defaults"=>{"host"=>"127.0.0.1", "port"=>27017}, "development"=>{"host"=>"127.0.0.1", "port"=>27017, "database"=>"tc_web_development"}, "test"=>{"host"=>"127.0.0.1", "port"=>27017, "database"=>"tc_web_test"}} I am wondering what may be the cause of this problem. Any ideas? Thanks.

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  • Distinct Value Array for View Controller Index Using Core Data

    - by b.dot
    Hi, I'm trying to create an index representing the first letter value of each record in a Core Data store to be used in a table view controller. I'm using a snippet of the code from Apple's documentation. I would simply like to produce an array or dictionary of distinct values as the result. My store already has the character defined within each record object. Questions: 1) I'm having a problem understanding NSDictionaryResultType. Where does the resulting dictionary object get received so that I can assign it's keys to the view controller? The code seems to only return an array. 2) If I include the line containing NSDictionaryResultType, I get no returns. 3) I realize that I could do this in a loop, but I'm hoping this will work. Thanks! NSEntityDescription *entity = [NSEntityDescription entityForName:@"People" inManagedObjectContext:managedObjectContext]; NSFetchRequest *request = [[NSFetchRequest alloc] init]; [request setEntity:entity]; [request setResultType:NSDictionaryResultType]; // This line causes no no results. [request setReturnsDistinctResults:YES]; [request setPropertiesToFetch :[NSArray arrayWithObject:@"alphabetIndex"]]; NSError *error; NSArray *objects = [managedObjectContext executeFetchRequest:request error:&error];

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  • Java downcasting and is-A has-A relationship

    - by msharma
    HI, I have a down casting question, I am a bit rusty in this area. I have 2 clasess like this: class A{ int i; String j ; //Getters and setters} class B extends A{ String k; //getter and setter} I have a method like this, in a Utility helper class: public static A converts(C c){} Where C are objects that are retireved from the database and then converted. The problem is I want to call the above method by passing in a 'C' and getting back B. So I tried this: B bClasss = (B) Utility.converts(c); So even though the above method returns A I tried to downcast it to B, but I get a runtime ClassCastException. Is there really no way around this? DO I have to write a separate converts() method which returns a B class type? If I declare my class B like: class B { String k; A a;} // So instead of extending A it has-a A, getter and setters also then I can call my existing method like this: b.setA(Utility.converts(c) ); This way I can reuse the existing method, even though the extends relationship makes more sense. What should I do? Any help much appreciated. Thanks.

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  • Java - How to declare table[i][j] elements as instance variables?

    - by JDelage
    All, I am trying to code a Connect4 game. For this, I have created a P4Game class and a P4Board class which represents the i X j dimensions of the Connect4 board. In P4Game, I have the following: public class P4Game{ //INSTANCE VARIABLES private int nbLines; private int nbColumns; private P4Board [][] position; //CONSTRUCTOR public P4Game(int nbLines, int nbColumns){ this.nbColumns = nbColumns; this.nbLines = nbLines; P4Board [][] position = new P4Board [nbLines][nbColumns]; //Creates the table to receive the instances of the P4Board object.*/ for (int i=0; i<nbLines; i++){ for (int j=0; j<nbColumns; j++){ this.position[i][j] = new P4Board(i,j); //Meant to create each object at (line=i, column=j) } } } This causes a NullPointerException in the nested loops where I mention this.position[i][j]. I reference those objects in other methods of this class so I need them to be instance variables. I suppose the exception is due to the fact that I have not listed the table element position[i][j] as an instance variable at the beginning of the class. my question to people here is (1) is my assumption correct, and if so (2) what would be the syntax to declare instance variables of this form? Thank you all for your help with what I realize is a very basic question. Hopefully it will also benefit other newbies. Cheers, JDelage

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  • Classic ASP application-wide initializations and object caching

    - by slack3r
    In classic ASP (which I am forced to use), I have a few factory functions, that is, functions that return classes. I use JScript. In one include file I use these factory functions to create some classes that are used throughout the application. This include file is included with the #include directive in all pages. These factory functions do some "heavy lifting" and I don't want them to be executed on every page load. So, to make this clear I have something like this: // factory.inc function make_class(arg1, arg2) { function klass() { //... } // ... Some heavy stuff return klass; } // init.inc, included everywhere <!-- #include FILE="factory.inc" --> // ... MyClass1 = make_class(myarg01, myarg02); MyClass2 = make_class(myarg11, myarg12); //... How can I achieve the same effect without calling make_class on every page load? I know that I can't cache the classes in the Application object I can't use the Application_OnStart hook in Global.asa I could probably create a scripting component, but I really don't want to do that So, is there something else I can do? Maybe some way to achieve caching of these classes, which are really objects in JScript. PS: [further clarification] In the above code "heavy stuff" is not so heavy, but I just want to know if there's a way to avoid it being executed all the time. It reads database meta information, builds a table of the primary keys in the database and another table that resolves strings to classes, etc.

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