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  • expand floating object when floating object within expands

    - by Scarface
    Hey guys, quick question, I have a link when clicked drops down a list. This list is floated to the right to position it properly. This list is in another box that has been floated. My problem is that when the list expands, the box does not and the list comes out of the container box, unless the list is not floated. However floating it seems like the only way to get it to the position I want. If anyone has any ideas on how to solve this problem I would appreciate it. .container-box { margin-top:0px; float:left; padding-left:5px; position:relative; } #box-within { float:right; font-weight:bold; max-height:250px; display: none; background-color:#fff; overflow: auto; width:325px; padding:5px; position:relative; }

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  • save object associate to another object automatically

    - by Luca Romagnoli
    Hi i have these classes: class Core < ActiveRecord::Base belongs_to :resource, :polymorphic => true belongs_to :image, :class_name => 'Multimedia', :foreign_key => 'image_id' end class Place < ActiveRecord::Base has_one :core, :as => :resource end If i try do launch this: a = Place.find(5) a.name ="a" a.core.image_id = 24 a.save name is saved. image_id no i want save automatically all changes in records in relationship with place class at a.save command. is possible? thanks

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  • Objective-C: alloc of object within init of another object (memory management)

    - by Stefan Klumpp
    In my .h file I have: NSMutableArray *myArray; @property (nonatomic, retain) NSMutableArray *myArray; My .m file looks basically like this: @synthesize myArray; - (id) init { self = [super init]; if (self != nil) { self.myArray = .... ? // here I want to create an empty array } return self; } - (void) dealloc { [self.myArray release]; [super dealloc]; } What I'm not sure about is what do to in the init. 1) self.myArray = [[NSMutableArray alloc] init]; 2) NSMutableArray *tmp = [[NSMutableArray alloc] init]; self.myArray = tmp; [tmp release]; Solution 1 doesn't seem right to me, because of my @property (retain) setting I automatically increase the retain counter when setting self.myArray, but additionally I have already a "+1 retain" due to the [NSMutableArray alloc]. Thus the second solution seems more correct to me, even though it is cumbersome. Also am I wondering if self.myArray = ... is actually the same as [self setMyArray:...] and thus does increase the retain count.

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  • Greatest not null column

    - by Álvaro G. Vicario
    I need to update a row with a formula based on the largest value of two DATETIME columns. I would normally do this: GREATEST(date_one, date_two) However, both columns are allowed to be NULL. I need the greatest date even when the other is NULL (of course, I expect NULL when both are NULL) and GREATEST() returns NULL when one of the columns is NULL. This seems to work: GREATEST(COALESCE(date_one, date_two), COALESCE(date_two, date_one)) But I wonder... am I missing a more straightforward method?

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  • ruby hash to object - Parsing data from JSON object

    - by Leddo
    Hi all, I'm just starting to dabble in consuming a JSON webservice, and I am having a little trouble working out the best way to get to the actual data elements. I am receiving a response which has been converted into a ruby hash using the JSON.parse method. The hash looks like this: {"response"=>{"code"=>2002, "payload"=>{"topic"=>[{"name"=>"Topic Name", "url"=>"http://www.something.com/topic", "hero_image"=>{"image_id"=>"05rfbwV0Nggp8", "hero_image_id"=>"0d600BZ7MZgLJ", "hero_image_url"=>"http://img.something.com/imageserve/0d600BZ7MZgLJ/60x60.jpg"}, "type"=>"PERSON", "search_score"=>10.0, "topic_id"=>"0eG10W4e3Aapo"}]}, "message"=>"Success"}} What I would like to know, is what is the easiest way to get to the "topic" data so I can do something like: topic.name = json_resp.name topic.img = jsob_resp.hero_image_url etc Many thanks for any help you can offer. Regards Chris

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  • C++ Type error with Object versus Object reference

    - by muddybruin
    I have the following function (which worked in Visual Studio): bool Plane::contains(Vector& point){ return normalVector.dotProduct(point - position) < -doubleResolution; } When I compile it using g++ version 4.1.2 , I get the following error: Plane.cpp: In member function âvirtual bool Plane::contains(Vector&)â: Plane.cpp:36: error: no matching function for call to âVector::dotProduct(Vector)â Vector.h:19: note: candidates are: double Vector::dotProduct(Vector&) So as you can see, the compiler thinks (point-position) is a Vector but it's expecting Vector&. What's the best way to fix this? I verified that this works: Vector temp = point-position; return normalVector.dotProduct(temp) < -doubleResolution; But I was hoping for something a little bit cleaner. I heard a suggestion that adding a copy constructor might help. So I added a copy constructor to Vector (see below), but it didn't help. Vector.h: Vector(const Vector& other); Vector.cpp: Vector::Vector(const Vector& other) :x(other.x), y(other.y), z(other.z), homogenous(other.homogenous) { }

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  • How should an object that uses composition set its composed components?

    - by Casey
    After struggling with various problems and reading up on component-based systems and reading Bob Nystrom's excellent book "Game Programming Patterns" and in particular the chapter on Components I determined that this is a horrible idea: //Class intended to be inherited by all objects. Engine uses Objects exclusively. class Object : public IUpdatable, public IDrawable { public: Object(); Object(const Object& other); Object& operator=(const Object& rhs); virtual ~Object() =0; virtual void SetBody(const RigidBodyDef& body); virtual const RigidBody* GetBody() const; virtual RigidBody* GetBody(); //Inherited from IUpdatable virtual void Update(double deltaTime); //Inherited from IDrawable virtual void Draw(BITMAP* dest); protected: private: }; I'm attempting to refactor it into a more manageable system. Mr. Nystrom uses the constructor to set the individual components; CHANGING these components at run-time is impossible. It's intended to be derived and be used in derivative classes or factory methods where their constructors do not change at run-time. i.e. his Bjorne object is just a call to a factory method with a specific call to the GameObject constructor. Is this a good idea? Should the object have a default constructor and setters to facilitate run-time changes or no default constructor without setters and instead use a factory method? Given: class Object { public: //...See below for constructor implementation concerns. Object(const Object& other); Object& operator=(const Object& rhs); virtual ~Object() =0; //See below for Setter concerns IUpdatable* GetUpdater(); IDrawable* GetRenderer(); protected: IUpdatable* _updater; IDrawable* _renderer; private: }; Should the components be read-only and passed in to the constructor via: class Object { public: //No default constructor. Object(IUpdatable* updater, IDrawable* renderer); //...remainder is same as above... }; or Should a default constructor be provided and then the components can be set at run-time? class Object { public: Object(); //... SetUpdater(IUpdater* updater); SetRenderer(IDrawable* renderer); //...remainder is same as above... }; or both? class Object { public: Object(); Object(IUpdater* updater, IDrawable* renderer); //... SetUpdater(IUpdater* updater); SetRenderer(IDrawable* renderer); //...remainder is same as above... };

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  • How do I handle specific tile/object collisions?

    - by Thomas William Cannady
    What do I do after the bounding box test against a tile to determine whether there is a real collision against the contents of that tile? And if there is, how should I move the object in response to that collision? I have a small object, and test for collisions against the tiles that each corner of it is on. Here's my current code, which I run for each of those (up to) four tiles: // get the bounding box of the object, in world space objectBounds = object->bounds + object->position; if ( (objectBounds.right >= tileBounds.left) && (objectBounds.left <= tileBounds.right) && (objectBounds.top >= tileBounds.bottom) && (objectBounds.bottom <= tileBounds.top)) { // perform specific test to see if it's a left, top , bottom // or right collision. If so, I check to see the nature of it // and where I need to place the object to respond to that collision... // [THIS IS THE PART THAT NEEDS WORK] // if( lastkey==keydown[right] && ((objectBounds.right >= tileBounds.left) && (objectBounds.right <= tileBounds.right) && (objectBounds.bottom >= tileBounds.bottom) && (objectBounds.bottom <= tileBounds.top)) ) { object->position.x = tileBounds.left - objectBounds.width; } // etc.

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  • Unity Problem with colliding instances of same object

    - by Kuba Sienkiewicz
    I want to check if object's instance is overlapping with another instance (any spawned object with another spawned object, not necessary the same object). I'm doing this by detecting collisions between bodies. But I have a problem. Spawned object (instances) are detecting collision with everything but other spawned objects. I've checked collision layers etc. All of spawned objects have rigidbodies and mesh colliders. Also when I attach my script to another body and I touch that body with an instanced object it detects collision. So problem is visible only in collision between spawned objects. And one more information I have script, rigid body and collider attached to child of main object. using UnityEngine; using System.Collections; public class CantPlace : MonoBehaviour { public bool collided = false; // Use this for initialization void Start () { } // Update is called once per frame void Update () { //Debug.Log (collided); } void OnTriggerEnter(Collider collider) { //if (true) { //foreach (Transform child in this.transform) { // if (child.name == "Cylinder") { //collided = true; Color c; c = this.renderer.material.color; c.g = 0f; c.b = 1f; c.r = 0f; this.renderer.material.color = c; Debug.Log (collider.name); //} // } //} //foreach (ContactPoint contact in collision.contacts) { // Debug.DrawRay(contact.point, contact.normal, Color.red,15f); // } } }

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  • Design Pattern for Skipping Steps in a Wizard

    - by Eric J.
    I'm designing a flexible Wizard system that presents a number of screens to complete a task. Some screens may need to be skipped based on answers to prompts on one or more previous screens. The conditions to skip a given screen need to be editable by a non-technical user via a UI. Multiple conditions need only be combined with and. I have an initial design in mind, but it feels inelegant. I wonder if there's a better way to approach this class of problem. Initial Design UI where The first column allows the user to select a question from a previous screen. The second column allows the user to select an operator applicable to the type of question asked. The third column allows the user to enter one or more values depending on the selected operator. Object Model public enum Operations { ... } public class Condition { int QuestionId { get; set; } Operations Operation { get; set; } List<object> Parameters { get; private set; } } List<Condition> pageSkipConditions; Controller Logic bool allConditionsTrue = pageSkipConditions.Count > 0; foreach (Condition c in pageSkipConditions) { allConditionsTrue &= Evaluate(previousAnswers, c); } // ... private bool Evaluate(List<Answers> previousAnswers, Condition c) { switch (c.Operation) { case Operations.StartsWith: // logic for this operation // etc. } }

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  • Visitor pattern and compiler code generation, how to get children attributes?

    - by LeleDumbo
    I'd like to modify my compiler's code generator to use visitor pattern since the current approach must use multiple conditional statement to check the real type of a child before generating the corresponding code. However, I have problems to get children attributes after they're visited. For instance, in binary expression I use this: LHSCode := GenerateExpressionCode(LHSNode); RHSCode := GenerateExpressionCode(RHSNode); CreateBinaryExpression(Self,LHS,RHS); In visitor pattern the visit method is usually void, so I can't get the expression code from LHS and RHS. Keeping shared global variables isn't an option since expression code generation is recursive thus could erase previous values kept in the variables. I'll just show the binary expression as this is the most complicated part (for now): function TLLVMCodeGenerator.GenerateExpressionCode( Expr: TASTExpression): TLLVMValue; var BinExpr: TASTBinaryExpression; UnExpr: TASTUnaryExpression; LHSCode, RHSCode, ExprCode: TLLVMValue; VarExpr: TASTVariableExpression; begin if Expr is TASTBinaryExpression then begin BinExpr := Expr as TASTBinaryExpression; LHSCode := GenerateExpressionCode(BinExpr.LHS); RHSCode := GenerateExpressionCode(BinExpr.RHS); case BinExpr.Op of '<': Result := FBuilder.CreateICmp(ccSLT, LHSCode, RHSCode); '<=': Result := FBuilder.CreateICmp(ccSLE, LHSCode, RHSCode); '>': Result := FBuilder.CreateICmp(ccSGT, LHSCode, RHSCode); '>=': Result := FBuilder.CreateICmp(ccSGE, LHSCode, RHSCode); '==': Result := FBuilder.CreateICmp(ccEQ, LHSCode, RHSCode); '<>': Result := FBuilder.CreateICmp(ccNE, LHSCode, RHSCode); '/\': Result := FBuilder.CreateAnd(LHSCode, RHSCode); '\/': Result := FBuilder.CreateOr(LHSCode, RHSCode); '+': Result := FBuilder.CreateAdd(LHSCode, RHSCode); '-': Result := FBuilder.CreateSub(LHSCode, RHSCode); '*': Result := FBuilder.CreateMul(LHSCode, RHSCode); '/': Result := FBuilder.CreateSDiv(LHSCode, RHSCode); end; end else if Expr is TASTPrimaryExpression then if Expr is TASTBooleanConstant then with Expr as TASTBooleanConstant do Result := FBuilder.CreateConstant(Ord(Value), ltI1) else if Expr is TASTIntegerConstant then with Expr as TASTIntegerConstant do Result := FBuilder.CreateConstant(Value, ltI32) else if Expr is TASTUnaryExpression then begin UnExpr := Expr as TASTUnaryExpression; ExprCode := GenerateExpressionCode(UnExpr.Expr); case UnExpr.Op of '~': Result := FBuilder.CreateXor( FBuilder.CreateConstant(1, ltI1), ExprCode); '-': Result := FBuilder.CreateSub( FBuilder.CreateConstant(0, ltI32), ExprCode); end; end else if Expr is TASTVariableExpression then begin VarExpr := Expr as TASTVariableExpression; with VarExpr.VarDecl do Result := FBuilder.CreateVar(Ident, BaseTypeLLVMTypeMap[BaseType]); end; end; Hope you understand it :)

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  • Another design-related C++ question

    - by Kotti
    Hi! I am trying to find some optimal solutions in C++ coding patterns, and this is one of my game engine - related questions. Take a look at the game object declaration (I removed almost everything, that has no connection with the question). // Abstract representation of a game object class Object : public Entity, IRenderable, ISerializable { // Object parameters // Other not really important stuff public: // @note Rendering template will never change while // the object 'lives' Object(RenderTemplate& render_template, /* params */) : /*...*/ { } private: // Object rendering template RenderTemplate render_template; public: /** * Default object render method * Draws rendering template data at (X, Y) with (Width, Height) dimensions * * @note If no appropriate rendering method overload is specified * for any derived class, this method is called * * @param Backend & b * @return void * @see */ virtual void Render(Backend& backend) const { // Render sprite from object's // rendering template structure backend.RenderFromTemplate( render_template, x, y, width, height ); } }; Here is also the IRenderable interface declaration: // Objects that can be rendered interface IRenderable { /** * Abstract method to render current object * * @param Backend & b * @return void * @see */ virtual void Render(Backend& b) const = 0; } and a sample of a real object that is derived from Object (with severe simplifications :) // Ball object class Ball : public Object { // Ball params public: virtual void Render(Backend& b) const { b.RenderEllipse(/*params*/); } }; What I wanted to get is the ability to have some sort of standard function, that would draw sprite for an object (this is Object::Render) if there is no appropriate overload. So, one can have objects without Render(...) method, and if you try to render them, this default sprite-rendering stuff is invoked. And, one can have specialized objects, that define their own way of being rendered. I think, this way of doing things is quite good, but what I can't figure out - is there any way to split the objects' "normal" methods (like Resize(...) or Rotate(...)) implementation from their rendering implementation? Because if everything is done the way described earlier, a common .cpp file, that implements any type of object would generally mix the Resize(...), etc methods implementation and this virtual Render(...) method and this seems to be a mess. I actually want to have rendering procedures for the objects in one place and their "logic implementation" - in another. Is there a way this can be done (maybe alternative pattern or trick or hint) or this is where all this polymorphic and virtual stuff sucks in terms of code placement?

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  • Find all ways to insert zeroes into a bit pattern

    - by James
    I've been struggling to wrap my head around this for some reason. I have 15 bits that represent a number. The bits must match a pattern. The pattern is defined in the way the bits start out: they are in the most flush-right representation of that pattern. So say the pattern is 1 4 1. The bits will be: 000000010111101 So the general rule is, take each number in the pattern, create that many bits (1, 4 or 1 in this case) and then have at least one space separating them. So if it's 1 2 6 1 (it will be random): 001011011111101 Starting with the flush-right version, I want to generate every single possible number that meets that pattern. The # of bits will be stored in a variable. So for a simple case, assume it's 5 bits and the initial bit pattern is: 00101. I want to generate: 00101 01001 01010 10001 10010 10100 I'm trying to do this in Objective-C, but anything resembling C would be fine. I just can't seem to come up with a good recursive algorithm for this. It makes sense in the above example, but when I start getting into 12431 and having to keep track of everything it breaks down.

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  • crontab still sending emails even with > /dev/null

    - by user2344668
    I have a crontab (root) that runs a script and output is set to /dev/null but I always get the emails whenever it runs. I only want to receive error emails. # Rackspace driveclient update (12pm MST) 0 12 * * * /root/scripts/driveclient-update > /dev/null The only way I can get it to turn off is to use /dev/null 2&1 but then I won't get error emails. This is happening on three different CentOS servers, two are 6.3 and one is 6.4. NOTE: I have read over and over that /dev/null is supposed to send stdout there and prevent the email if there is nothing but stdout from the script, so at works for at least some people; I cannot figure out why it is not working on these servers. Here's an example of where /dev/null is supposed to work: http://www.alphadevx.com/a/384-Suppressing-Cron-Job-Email-Notifications

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  • /dev/null file became regular file

    - by user197719
    In our production server suddenly /dev/null became a regular file and due to this sshd service got stopped and not able to login the server. And also we tried to the below steps to configure back to character device file, rm -rf /dev/null mknod /dev/null c 1 3 As soon as we run the rm command /dev/null is being re-created as a regular file before mknod can run. We can't figure out how this happening and which component is creating this file. So until we solve this issue we are unable to create /dev/null as character device file.

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  • JavaScript local alias pattern

    - by Bertrand Le Roy
    Here’s a little pattern that is fairly common from JavaScript developers but that is not very well known from C# developers or people doing only occasional JavaScript development. In C#, you can use a “using” directive to create aliases of namespaces or bring them to the global scope: namespace Fluent.IO { using System; using System.Collections; using SystemIO = System.IO; In JavaScript, the only scoping construct there is is the function, but it can also be used as a local aliasing device, just like the above using directive: (function($, dv) { $("#foo").doSomething(); var a = new dv("#bar"); })(jQuery, Sys.UI.DataView); This piece of code is making the jQuery object accessible using the $ alias throughout the code that lives inside of the function, without polluting the global scope with another variable. The benefit is even bigger for the dv alias which stands here for Sys.UI.DataView: think of the reduction in file size if you use that one a lot or about how much less you’ll have to type… I’ve taken the habit of putting almost all of my code, even page-specific code, inside one of those closures, not just because it keeps the global scope clean but mostly because of that handy aliasing capability.

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  • Dynamic Forms: Pattern or AntiPattern?

    - by Segfault
    I'm sure you've seen it. The database has a bunch of tables called Forms, Controls,FormsControls, ControlSets, Actions and the program that queries these tables has a dynamically generated user interface. It will read all the forms, load a home page that has links to them all, or embed them in some tabbed or paged home page, and for each of those forms it will read the various text boxes, check boxes, radio buttons, submit buttons, combo boxes, labels and whatnot from the controls and form-to-control join tables, lay those elements out according to the database and link all the controls to logic according to other rules in the database. To me, this is an anti-pattern. It actually make the application more difficult to maintain because the design of it is now spread out into multiple different systems. Also, the database is not source controlled. Sure, it may make one or two changes go more quickly, after you've analyzed the program anyway to understand how to change the data and as long as you don't stray from the sort of changes that were anticipated and accounted for, but that's often just not sustainable. What say you?

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  • Design pattern for procedural terrain assets

    - by Alex
    I'm developing a procedural terrain class at the moment and am stuck on the correct design pattern. The terrain is 2D and is constructed from a series of (x,y) points. I currently have a method that just randomly adds points to an array of points to generate a random spread of points. However I need a more elaborate system for generating the terrain. The terrain will be built form a series of re-accuring terrain structures eg. a pit, jump, hill etc. Each structure will have some randomness assigned to it, each height of hill will be random, pit size will be random etc. Each terrain structure will have: A property detailing the number of points making up that structure A method for generating the points (not absolutely necessary) My current thinking is to have a class for each terrain structure, create a fixed amount of terrain elements ahead of the player, loop over these and add the corresponding points to the game. What is the best way to create these procedural terrain structures when they are ultimately just a set of functions for generating terrain elements? Is a class for each terrain element excessive? I'm developing the game for iphone so any objective-c related answers would be welcome.

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  • Producer-consumer pattern with consumer restrictions

    - by Dan
    I have a processing problem that I am thinking is a classic producer-consumer problem with the two added wrinkles that there may be a variable number of producers and there is the restriction that no more than one item per producer may be consumed at any one time. I will generally have 50-100 producers and as many consumers as CPU cores on the server. I want to maximize the throughput of the consumers while ensuring that there are never more than one work item in process from any single producer. This is more complicated than the classic producer-consumer problem which I think assumes a single producer and no restriction on which work items may be in progress at any one time. I think the problem of multiple producers is relatively easily solved by enqueuing all work items on a single work queue protected by a critical section. I think the restriction on simultaneously processing work items from any single producer is harder because I cannot think of any solution that does not require each consumer to notify some kind of work dispatcher that a particular work item has been completed so as to lift the restriction on work items from that producer. In other words, if Consumer2 has just completed WorkItem42 from Producer53, there needs to be some kind of callback or notification from Consumer2 to a work dispatcher to allow the work dispatcher to release the next work item from Producer53 to the next available consumer (whether Consumer2 or otherwise). Am I overlooking something simple here? Is there a known pattern for this problem? I would appreciate any pointers.

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