In my application, I am using a plist. Please, can anyone explain what are the uses of plist with an example or a sample code?
In the context of iPhone development, Property Lists are a key-value store that your application can use to save and retrieve persistent data.
All iPhone applications have at least one of these by default, the Information Property List:
The information property list is a
file named Info.plist that is included
with every iPhone application project
created by Xcode. It is a property
list whose key-value pairs specify
essential runtime-configuration
information for the application. The
elements of the information property
list are organized in a hierarchy in
which each node is an entity such as
an array, dictionary, string, or other
scalar type.
Plist are XML files in a specific format. Prior to XML, they had a custom format now called 'old plist'. (You almost never see that anymore save in legacy code.)
Foundations collection classes automatically generate XML files in the plist format when you use their serialization methods to write them to disk. They also automatically read them back. You can also write your own serializers for your own custom objects. This allows you to persistently store complex objects in a robust, human readable format.
One use for plist for programmers is that it is easier to use the plist editor to input and manage a lot of data than it is to try and code it. For example, if you have an class that requires setting a large number of ivars, you can create a plist, read it into an NSArray or NSDictionary and then initialize the instance by passing it the dictionary.
I use this technique when I have to use a large number of paths to draw complex objects. You define the path in the plist file instead of the code and edit the path in the plist editor.
It's also a handy way to create a large amount of detailed test data.
PList means PropertyList
It is XML file format
It is mainly user for store and reterve the data
It can store the key-value pair
It's been a long time since I've looked at them, but plist is a short-form of "properties list" and can be used to store application configuration settings that need to persist between instances of an application's execution. Could be similar to a .properties file (I see those a lot on Java projects).
A plist is essentially just a data file, it stores information in a documented format.
From Wikipedia:
In the Mac OS X Cocoa, NeXTSTEP, and
GNUstep programming frameworks,
property list files are files that
store serialized objects. Property
list files use the filename extension
.plist, and thus are often referred to
as plist files. Property list files
are often used to store a user's
settings. They are also used to store
information about bundles and
applications, a task served by the
resource fork in the old Mac OS.
.plist
Info.plist is key/value persistence storage(property list) which is used by system and user. It contains user-friendly text in XML format. Info.plist is mandatory file for any Bundle. For example it contains Bundle id[About] which is usually is used by system but as a programmer/user you are not limited on changing/reading[More]. The same as you can add K/V for your own purposes and read it in runtime. You could noticed that some frameworks forces you to add K/V into your's application to identify you or some other cases.
.entitlements is a property list with enabled capabilities(e.g. ApplePay)
[Info.plist location]
[Vocabulary]
Related
I should use different API keys for different schemes (like Debug, QA, Release).
And I want to use a custom .plist file for that (Config.plist). Not other ways because of my project's architecture.
I configured User-Defined Settings in Build Settings
I followed these steps:
Create a custom User-Defined Settings named MY_API_KEY,
Add API key to different schemes,
Create a new Config.plist's User-Defined Settings for read from Info.plist,
Write CONFIG_FILE to Info.plist,
Write MY_API_KEY to the custom plist (Config.plist),
So I want to read MyAPIKey value from Config.plist but it returns ${MY_API_KEY} as a String.
Expected result is "asdfsadf" (value from User-Defined Settings).
NOTE:
I didn't post my way for read values from plists because I'm using my custom services for read plists.
First of all, you should use parentheses instead of curly braces:
So change this:
${MY_API_KEY}
${CONFIG_FILE}
to this:
$(MY_API_KEY)
$(CONFIG_FILE)
And second of all, why you don't use different info.plist files for different environments?
You can use info.plist File attribute to assign different plist files for different environments:
So you can have entirely custom plist file per environment.
This may seem like a stupid question. But I have a plist for different categories in a iPhone application.
categories.plist
<key>cat1</key>
<string>Players</string>
...
Is it possible to localize this strings? This categories are created in to Core Data when the app is started for the first time. And if the user changes language after first launch the category names will still be in the language as when the application was first launched.
Is it possible in some way to localize the strings in the plist?
You can easily localize the entire file. Just select the file in Xocde and click the + button in the Localization section of the File Inspector to add multiple languages. You can then translate the file for each language.
If you just want to translate the strings, I would put keys into the plist file and translate those keys via the normal Localizable.strings file. In your code, you would then not use the strings directly but translate them first with NSLocalizedString().
you would typically create a plist file for each localization (not individual keys).
since that would duplicate the categories in each localization and in many cases only the translations change (not necessarily other keys), you could work around this if you use a separate lookup table (plist) for the localized translations of the values in the category plist. then you would use the category plist keyed values as keys for another localized lookup table (which would need only strings).
What does this file hold and how important is it to keep it "correct"?
I've seen people write scripts to just merge any change dealing with it and I've heard others merging it manually every time.
What is the correct way to handle it and why?
The project.pbxproj contains all of the metadata about your project that Xcode uses to build it; the settings, the file references, configuration, targeted platforms, etc...
I.e. it is a critically important.
There really isn't a great answer for this. Typically, teams will avoid conflict by limiting edits to the project to one team member at a time.
The Xcode team has put a lot of effort into making the file merge-friendly. In managing several large projects via svn, I've generally found that the merges are automatic and painless.
Until they aren't. And when they aren't, revert, merge changes by hand (i.e. make the changes in the project that conflicted), and move on.
Try my script xUnique.
What it does:
convert project.pbxproj to JSON format
Iterate all objects in JSON and give every UUID an absolute path, and create a new UUID using MD5 hex digest of the path
All elements in this json object is actually connected as a tree
We give a path attribute to every node of the tree using its unique attribute; this path is the absolute path to the root node,
Apply MD5 hex digest to the path for the node
Replace all old UUIDs with the MD5 hex digest and also remove unused UUIDs that are not in the current node tree and UUIDs in wrong format
Sort the project file inlcuding children, files, PBXFileReference and PBXBuildFile list and remove all duplicated entries in these lists
see sort_pbxproj method in xUnique.py if you want to know the implementation;
It's ported from my modified sort-Xcode-project-file, with some differences in ordering PBXFileReference and PBXBuildFile
With different options, you can use xUnique with more flexibility
i was thinking about, how to organize "normal" text content (i.e a String, HTML Code ...) in Jackrabbit.
Are there any recommended structures for plain text content (like for files)?
Should i store each text content as a binary (like i do with files)
Node(nt:folder)--> Node(nt:file) --> Node(jcr:content with a jcr:data property which holds the binary)
Or is it better to have something like
Node(nt:folder)--> Node(nt:unstructured with a jcr:message property which holds the string)
My third idea was to create a separate name space for text content
Node(nt:folder)--> Node(my:text with a jcr:message property which holds the string)
Node(nt:folder)--> Node(my:html with a jcr:message property which holds the string)
...
What do you thing is the best solution?
It would be great to discuss this.
Storing text and html content as nt:file structures makes it visible via WebDAV and other tools that understand those structures. That can be useful depending on your application.
If you don't need this, you can just store your textual content as properties. In this case, using standard property names: jcr:title, jcr:description etc. as defined in the Standard Application Node Types section of the JSR-283 spec helps make things consistent.
See also http://wiki.apache.org/jackrabbit/DavidsModel which has some related recommendations.
I would store regular text in a string property, unless it's a large (multi-kilobyte) text. This is similar to VARCHAR in a relational database.
For really large texts that are not 'files', I would use a binary property (a stream). Such properties are stored in the DataStore, which is slower to write and access than a string property, but will not load the whole item in memory, and will only store the same data once. This is similar to BLOB / CLOB in a relational database.
For files, I would use nt:folder / nt:file. This is similar to a file in a file system.
I'm currently making a word game for iOS that, when loading, reads in a text file of around 30000 words and loads them into a prefix tree for quick searching during gameplay. This works well, but the loading and tree construction process adds a noticeable few seconds to the app's startup time. At the moment I'm testing on an iPhone 4, but I imagine it would be a good deal slower on a 3GS earlier models.
Is there a way to create this tree at compile time rather than when the app opens? Or, less ideally, would it be possible to prebake the data with another program and add that file to the project instead of doing it at runtime? How would I go about doing that?
I run into the same issue with a game we developed, and for us, it performed better to use a SQLite DB with the words instead of the in-memory tree. The DB used less space than the plist that represented the tree, it did not require us to preload it in memory, and the performance (when querying for a valid word) was about the same.
pgb's answer is good. If you do not want to use SQLite, you can store your data in a plist and have [NSDictionary dictionaryWithContentsOfFile:] create a tree for you.
If you do choose to have the data compiled into your program, it will have to be built of primitive types, such as numbers and characters. Then, use structures and arrays to define the structure, and use a constant variable to store the data. Here is a simple example which is just an array of character strings:
const char *words[] = {"Word1","Word2","Word3"};
const unsigned numWords = (sizeof(words) / sizeof(char*));