Questions tagged [composite]
The Composite pattern is a design pattern that allows a group of objects to be treated in the same way as a single instance of an object. It is one of the Gang of Four's structural design patterns.
composite
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How to clear the canvas for redrawing
After experimenting with composite operations and drawing images on the canvas I'm now trying to remove images and compositing. How do I do this?
I need to clear the canvas for redrawing other images;...
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votes
5
answers
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How do composite indexes work?
I've created composite indexes (indices for you mathematical folk) on tables before with an assumption of how they worked. I was just curious if my assumption is correct or not.
I assume that when ...
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votes
11
answers
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When should I use composite design pattern?
I don't understand when I should use composite design pattern.
What kinds of benefits will I get from this design pattern?
I visited this website but it only tells me about the structure of the design ...
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68
votes
7
answers
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Difference between the Composite Pattern and Decorator Pattern?
What is the difference between the Composite Pattern and Decorator Pattern?
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Relations on composite keys using sqlalchemy
I have this simple model of Author - Books and can't find a way to make firstName and lastName a composite key and use it in relation. Any ideas?
from sqlalchemy import create_engine, ForeignKey, ...
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votes
1
answer
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SQL join with composite primary key
I have to join two tables.
But in one table primary key is not there,composite primary key is there,means three columns put together uniquely define a row of that table.
I have those three columns in ...
- 501
42
votes
0
answers
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How to make a composite manifest for Microsoft smooth streaming
I am new to Microsoft Smooth Streaming and have questions about the making of composite manifests.
Following the guidance from here.
I was able to make a composite manifest of a single clip element ...
- 671
39
votes
1
answer
21k
views
Design patterns: Composite vs. Composition
I am finishing a course on design patterns, and while reviewing the notes came across something I missed during the semester: Composite vs. Composition. What I managed to understand is that composite ...
- 21k
33
votes
2
answers
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Check if a Postgres composite field is null/empty
With postgres composite types you can basically build a field with the structure being defined as another table. I have the composite field called "recipient" of type "person". This recipient field is ...
- 13.4k
33
votes
6
answers
12k
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Implementing MEF with ASP.NET MVC?
I am trying to find out if anyone has any experience or ideas of using MEF (Managed Extensible Framework (Microsoft's new plugin framework) with ASP.NET MVC. I need to create a standard ASP.NET MVC, ...
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30
votes
2
answers
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MySQL: how to index an "OR" clause
I'm executing the following query
SELECT COUNT(*)
FROM table
WHERE field1='value' AND (field2 >= 1000 OR field3 >= 2000)
There is one index over field1 and another composited over field2&...
- 11.8k
29
votes
3
answers
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views
how can I set up multiple listeners for one event?
I want to set up multiple listeners for one event, and have found that using composite listener is the key.
Could anyone give me an example?
- 1,389
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votes
15
answers
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When are interfaces needed?
(In the context of .NET for what its worth)
I tend to not use inheritance and rarely use interfaces. I came across someone who thinks interfaces are the best thing since spit. He uses them ...
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26
votes
4
answers
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views
How do I configure a RollingFileAppender to roll by date and size with log4net?
I am configure log4net to use a composite RollingFileAppender so that the current file is always named logfile.log and all subsequent files are named logfile-YYYY.MM.dd.seq.log where seq is the ...
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votes
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answers
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How do I dynamically set an environment variable in a github composite action step?
I do need it to be an environment variable and this is for a composite action specifically.
In a composite action, I've tried many different ways of setting environment variables. The only way I've ...
- 1,033
24
votes
2
answers
10k
views
composed_of in Rails - when to use it?
When should you use ActiveRecord's composed_of class method?
user65663
20
votes
8
answers
16k
views
Composite primary key
I am working on the design of a database that will be used to store data that originates from a number of different sources. The instances I am storing are assigned unique IDs by the original sources. ...
- 4,153
18
votes
4
answers
9k
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The composite pattern/entity system and traditional OOP
I'm working on a small game written in Java (but the question is language-agnostic). Since I wanted to explore various design patterns, I got hung up on the Composite pattern/Entity system (which I ...
- 32.9k
16
votes
4
answers
3k
views
Imagick: compose with mask
I try to recreate a script that uses the ImageMagick command "convert" to compose an image. But I want to do the same in PHP using Imagick (version 6.6.2-10).
The command is as follows:
convert A1....
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15
votes
6
answers
13k
views
How to do composite with gm node.js?
How to do 'gm composite -gravity center change_image_url base_image_url' with GM Node.js?
How to call gm().command() & gm().in() or gm().out() to achieve the above?
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3
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A tree, where each node could have multiple parents
Here's a theoretical/pedantic question: imagine properties where each one could be owned by multiple others. Furthermore, from one iteration of ownership to the next, two neighboring owners could ...
- 1,260
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votes
2
answers
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Java AWT custom CompositeContext & anti-aliasing: RasterFormatException when drawing outside of the client area
I am trying to implement SWT GC-like xor-mode drawing for an AWT Graphics2D. Using the built-in XORComposite is not an option as it does not implement xor-mode drawing as in SWT.
The SWT xor-mode ...
- 1,005
14
votes
6
answers
24k
views
How to set value of composite variable field using dynamic SQL
Given this type:
-- Just for testing purposes:
CREATE TYPE testType as (name text)
I can get the value of a field dynamically with this function:
CREATE OR REPLACE FUNCTION get_field(object ...
- 5,907
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votes
4
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4k
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Is the Composite Pattern SOLID?
A Leaf in the Composite Pattern implements the Component interface, including Add, Remove, and GetChild methods that a Leaf is never going to use. This seems to be a violation of the Interface ...
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4
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3k
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Django Class Based View Composite
I'm using Django 1.3's Class-base generic views for a project. They're really nice but I would like to be DRYer. I have a page that displays a list of press coverage we've received and another which ...
- 525
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3
answers
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WPF, Prism v2, Region in a modal dialog, add region in code behind
I have a composite WPF application. In one of my modules I want to make a wizard and have the steps show up in a region so I can switch between the steps easier. Originally I had this wizard showing ...
- 1,517
12
votes
1
answer
12k
views
ImageMagick: Layering Images with convert -composite with gravity center
background
overlay
composite -gravity center overlay.png background.jpg result1.jpg
result1.jpg
convert -composite background.jpg overlay.png -gravity center result2.jpg
result2.jpg
...
- 9,154
12
votes
3
answers
1k
views
Possibility to mix composite pattern and curiously recurring template pattern
I have a composite pattern implementation, used for GUI components:
class CObject {
private:
CObject * m_pParent;
CObjectContainer * m_pChildren;
void private_foo() {
this->foo();
...
11
votes
2
answers
9k
views
How do I associate a keypress with a DelegateCommand in Composite WPF?
I am building a composite application using CAL/Prism. The main region is a tab control, with multiple types of views in it. Each view has a custom set commands that it can handle which are bound to ...
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2
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Composite Index vs. INCLUDE Covering Index in SQL Server
I understand that Composite Indexes are always used Left to Right (e.g. if an Index was on City, State, WHERE City = "Blah" or WHERE City = "Blah" AND State = "AA" would work fine but WHERE State = "...
- 1,554
11
votes
4
answers
316
views
What design pattern to use for generating multiple simulations?
I have a simulation that runs at a specific height and a specific temperature:
interface IGeneratable
{
string Name { get; }
void Generate();
}
interface ISimulation : IGeneratable
{
...
- 1,915
11
votes
2
answers
3k
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Composite foreign key columns in GORM
I need to customize the column names for composite foreign keys in GORM, and I didn't find any document that shows how to do it. I know how to customize PK columns, and how to customize a single-...
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3
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Using Interpreter pattern on a Composite structure
I've been asked to make an expression evaluator using Composite, Recursive Descendent Parser and Interpreter.
Here's the grammar :
<cond> → <termb> [OR <termb>]*
<termb>→<...
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votes
3
answers
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Is it alright to put data members in an interface?
Recently, I've learnt about composite pattern. I want to use it in my assignment which I have to implement File and Folder classes. I realize that sub-classes like CFile and Cfolder got to have the ...
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3
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REST returning an object graph
I am new to the REST architecural design, however I think I have the basics of it covered.
I have a problem with returning objects from a RESTful call. If I make a request such as http://localhost/{...
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How to get child views from Backbone Marionette's composite view?
I am working on an application based on Backbone and Marionette. I am using composite view to show an table now I want to update multiple child view's together So I want their object and model. So to ...
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10
votes
3
answers
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python, wrap and object into a list if not is an iterable
I want to have a function that wraps and object in an iterable one in order to allow
the clients of the function treat the same way collections and single objects, i did the following:
def to_iter(...
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Implementing a composite pattern using MVC/Backbone.js
My webapp has a composite structure i.e. each Category collection can contain a mixture of individual Items and other Categories as its rows/nodes/children (not sure of the correct terminology here). ...
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10
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1
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views
Composite property object that inhibits multiple signal emissions when all subobjects are changed
I have a simple property<T> class with a value_changed<T> which you can connect/disconnect to and receive or inhibit events when value_changed<T>::emit(T) is called. Think Qt signal/...
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Volume rendering: confusion with front-to-back compositing
In, for example, GPU Gems the front-to-back compositing equation (for colour) is
C'i = (1 - A'i-1)Ci + C'i-1
where C'i is the output accumulated colour value; A'i-1 is the accumulated alpha (opacity)...
- 1,334
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votes
0
answers
562
views
ASTs: prefer inheritance or variants? [closed]
In object oriented languages, it is fairly common to implement ASTs (Abstract Syntax Trees) using simple hierarchies (the Composite pattern), and to traverse them via visitors.
In functional ...
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Difference between a WebControl and a CompositeControl? [duplicate]
I have been looking around on the web and found some articles about the topic, but i still can't figure out the difference between them. I have the code show below, if i inherit from a ...
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1
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How to formulate an array literal of a composite type containing arrays?
I have a composite type like
CREATE TYPE example AS (id integer, some_stuff integer[]);
Thought I can use an array of this type as an argument of a function. The only problem is I couldn't find a ...
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1
answer
2k
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Build To Order Products in WooCommerce -- overriding product combinations
I am trying to set up a site with very complex "build to order" products. I am using WooCommerce but I realize that it might not be best solution, however, I am not a programmer so I'm trying to work ...
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1
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PostgreSQL: how to return composite type
I'm trying to get a composite value with a stored function in PostreSQL as follows.
I created a type called PersonId, and I used the type in a table called Person.
And I inserted values into the ...
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2
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GWT Composite best practices
I'm learning GWT and have started to get the hang of it. I'm at the point where my code is getting to be a spaghetti mess so I'm going back and factoring reasonable bits of it out as Composites. The ...
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Iterating hierarchy of nodes - Visitor and Composite?
Let's imagine I have a collection of nodes that I use for my Renderer class later on. Then I have a Visitor class that can visit node or whole collection. It's simple because my collection of nodes it'...
- 8,542
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What is 'composite pattern'?
Could anybody please explain and give a real-live example of Composite Design Pattern?
8
votes
1
answer
4k
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HTML5 Canvas compositing (source-in)
I am trying to recreate a page flipping type animation in HTML5 using canvas. The animation is based on ideas from this page. But that's not really important. The problem I am having is that using the ...
user281577
7
votes
1
answer
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Image compositing
I have an album title of some music band. I want to draw it with some mask which will round the corners of image.
So, I've prepared such mask in gimp:
I'm using white mask, but it's invisible at ...
- 63.2k