This question is more to figure out how to look up classes and objects in objective-c but i lack the knowledge to figure out how to look this up so i pose the question here.
In .Net if i had a MyObject.MyValue the MyValue would be called a property, and I could look this up in MSDN. In java i would check the javadocs online (and that property would have to be a value).
With objective-c that is called a ? and if i wanted to look it up i would look where?
Example:
//Object.???
UIImage.backgroundColor = [UIColor blueColor];
In obj-c it's called a "property" and you would look it up either here or in the developer documentation in Xcode by going to "Help -> Documentation"
I prefer using the built-in documentation, it's super fast and very well organized.
hover your mouse over "backgroundColor" and hit "option" and mouse click to bring up the documentation. The documentation will tell you more about the class property or method.
Related
I'm used to work with NetBeans and now I'm trying IntelliJ. So my question is: Does IntelliJ has a way to get right class by its methods?
For example, in NetBeans if I write:
glGenBu // Intellisense will kick in and will suggest me
to use GL15.glGenBuffers() method from GL15 class
This will automatically import the right library.
This is very handy because I'm working with LWJGL and it has a bad way to manage OpenGL methods ('GLXX' where XX is the version of OpenGL and all methods that appeared in that version are stored in that class) and I never remember the right class where my desired method is.
Thank you.
Pressing Ctrl+Space when you already see completion list will show more suggestions, with static methods from the entire project among them. See https://www.jetbrains.com/help/idea/auto-completing-code.html for more details.
I've inherited a collection of mostly undocumented QML code. I'm new to QML, and I'm struggling to understand this code. In particular, the construct
expression: "connected == false"
occurs frequently in various items, but I can't find any documentation on what this property does. It does not seem to be defined anywhere in the existing code collection, so I'm assuming it's part of QML, but I'm having no luck turning it up anywhere.
It looks as though all items using this construct are backed by C++ classes. However, "expression" is not defined as a QPROPERTY anywhere in the C++ code.
Nope, there's no such property in QML. You'll have to look into the QML file for the type that it's used in, or the C++ if it's declared there.
I am learning Objective-C Cocoa programming for OS X, and object-based programming in general, so I am a big novice here, so my question is a bit general and my guess is the answer to this is simply "experience"; however, I am curious if there is some route of knowledge to understanding what methods in various classes are best or perhaps required for getting tasks done.
For example, in a programming guide I am instructed to create a document-based program, and the document class contains an array to store data, with the following method bound to a button to create a new entry in the array:
- (IBAction)insertItem:(id)sender {
if (!theItems) {
theItems = [NSMutableArray array];
}
[theItems addObject:#"Double-click to edit."];
[theTableView reloadData];
[self updateChangeCount:NSChangeDone];
}
The array is "theItems" and its data is being presented in a TableView object. I understand that the steps here add a new string to the array and then refresh the table to display it, followed by setting the document to be set to an unsaved state.
What I am not getting is how one would know these specific steps and methods are required. Intuitively it seems one would just add items to the array, and that would be all that's required to have the new values simply show up in the table view for which the array is the data source, so how would one know that the tableView would need to be refreshed with the "reloadData" call? I can see someone (myself) figuring it out by trial and error, but is there some quick resource or guide (ie, some quick flow-chart) either in XCode or elsewhere that indicates for a table view that this would have to be a required action to display the new entry?
If I look at Apple's NSTableView class reference, it claims in the overview that you "modify the values in the data source and allow the changes to be reflected in the table view" which suggest the view is updated automatically, so the requirement to call "reloadData" on the view seems a little obscure.
Look for the guides. In the online class reference for NSTableView, there's a section at the top called "Companion Guides". For NSTableView, it lists the Table View Programming Guide for Mac. (In the prerelease 10.10 docs, the guides are listed under Related Documentation in the left-hand sidebar.)
I could have sworn this same information was available in Xcode's Documentation window, albeit somewhat hidden behind a "More related items" pseudo-link, but when I check right now there's no link to the guide anywhere in the NSTableView class reference. Which is a terrible oversight.
You can also browse or search the Guides section of the developer library.
Familiarity, studying the documentation and possibly reading some good books is the answer. For example, in the docs you quoted (emphasis mine)
you should modify the values in the data source and allow the changes to be reflected in the table view
You should do both these things. If you want it to happen "automatically", look into bindings, which uses several other Cocoa features you won't understand at this point either to do the table data source stuff for you. I'd recommend understanding what is happening manually before handing over control to bindings, so you have some chance of understanding when things go wrong.
As well as looking at the table view documentation, you also need to study the cell, delegate and datasource references. All of those objects work together to give you the functioning table view.
When I'm typing up a Cocoa object and calling a selector on that object, I sometimes can see 'documentation' or 'help' information about that method. For instance, as I type [NSArray alloc], I see two help hints. One for NSArray, and one for alloc. Both of these appear in the popup autocomplete suggestions listbox as I type the code.
How do I produce similar method/class decorated help hints which will appear when I type? I want to see my comments as I type my custom class name and custom methods. How can I do this?
For instance, C# provides this feature through XML documentation which can be placed before any method, class, or interface/protocol declaration.
You have to create a “docset”. There are tools like appledoc for creating docsets from your comments. You could set up a build phase that runs appledoc on your code.
The problem is that there's no way to make Xcode 4 reload a docset except by restarting Xcode. So even if you run appledoc automatically as part of your build, you will have to restart Xcode to make it see the changes to your docset.
Is there any solution in to make comments before each method in Obj C code similar to from from C#? I'd like to provide an information about my custom methods by Alt + Double mouse click when browsing code.
In objective-c doesn't exists a standard way to comment your code.
I can suggest you to use doxygen, doxygen use a syntax similar to JavaDoc and can generate Docset that xcode can load and use for suggestion.
I understand that this isn't trivial like in C# but for a brief introdution about Doxygen syntax, Usefull script and how to generate Xcode docset take a look at:
http://www.duckrowing.com/2010/03/18/documenting-objective-c-with-doxygen-part-i/
http://www.duckrowing.com/2010/03/18/documenting-objective-c-with-doxygen-part-ii
there is none, no Summary , no Regions