iphone - Retain counts of IBOutlets -

-

while coding same questions concerning retain counts of iboutlets came along: retain count after unarchiving object nib? when use @property's iboutlet? retain or assign while setting? differences between mac , iphone?

so read the nib object life cycle apple's documentation. test apps on mac , iphone gave me strange results. nevertheless wrote down few rules how handle issue stay happy while coding wanted verify community , listen opinions , experiences:

  1. always create iboutlet top-level objects. non-top-level objects if necessary (access needed).
  2. always provide property follows iboutlets (and release them necessary!):
    • top-level objects on mac:
      • @property (nonatomic, assign) iboutlet someobject *someobject;
      • @synthesize someobject;
      • [self.someobject release];
    • non-top-level objects on mac (no release):
      • @property (nonatomic, assign) iboutlet nswindow *window;
      • @synthesize someobject;
    • top-level objects on iphone (must retain):
      • @property (nonatomic, retain) iboutlet someobject *someobject;
      • @synthesize someobject;
      • [self.someobject release];
    • non-top-level objects on iphone (should retain):
      • @property (nonatomic, retain) iboutlet uiwindow *window;
      • @synthesize window;
      • [self.window release];

side notes:

  • on mac , iphone outlet connections made setter if available.
  • top-level objects: "have [...] no owning object"
  • non-top-level objects: "any objects have parent or owning object, such views nested inside view hierarchies."

so question be: is correct , practice?

i hope can approve or correct it.

always have nibs' file's owner subclass of nswindowcontroller or nsviewcontroller (on mac os x) or uiviewcontroller (on iphone), , use @property (retain) iboutlet of outlets, doing appropriate releases in controller subclass -dealloc method.

this pattern work fine on both mac os x and iphone os, because nswindowcontroller , nsviewcontroller on mac os x take implicit ownership of top-level objects (and relinquish in own -dealloc methods), , iphone os doesn't take implicit ownership of top-level objects during nib loading.


Comments

Post a Comment

Popular posts from this blog

unicode - Are email addresses allowed to contain non-alphanumeric characters? -

-
i'm building website using `django. website have significant users non-english speaking countries. i want know if there technical restrictions on types of characters email address contain. are email addresses allowed contain english alphabets, numbers, "_", "@" , "."? are allowed contain non-english alphabets "é" or "ü"? are allowed contain chinese or japanese or other unicode characters? email address consists of 2 parts local before @ , domain goes after. rules these parts different: for local part can use ascii: latin letters - z - z digits 0 - 9 special characters !#$%&'*+-/=?^_`{|}~ dot ., not first or last, , not in sequence space , "(),:;<>@[] characters allowed restrictions (they allowed inside quoted string, backslash or double-quote must preceded backslash) plus since 2012 can use international characters above u+007f , encoded as utf-8 . domain part more res...
Read more

C#: Application without a window or taskbar item (background app) that can still use Console.WriteLine() -

-
i'm trying create application adheres following: no taskbar no console or form window can utilize console.writeline() . (i.e. if executes app command prompt write console.) the problem if create windows form (or wpf) application can have there no taskbar, console or window show up, console.writeline() nothing. if create console app, writes console, can't figure out how hide (and if did hide it, write command prompt window?)... how do this? just create standard console application. callers responsibility hide window caused program (from how run c# console application console hidden ): system.diagnostics.processstartinfo start = new system.diagnostics.processstartinfo(); start.filename = dir + @"\myprocesstostart.exe"; start.windowstyle = system.diagnostics.processwindowstyle.hidden;
Read more

c++ - Convert big endian to little endian when reading from a binary file -

-
this question has answer here: how convert between big-endian , little-endian values in c++? 28 answers i've been looking around how convert big-endian little-endians. didn't find solve problem. seem there's many way can conversion. anyway following code works ok in big-endian system. how should write conversion function work on little-endian system well? this homework, since systems @ school running big-endian system. it's got curious , wanted make work on home computer also #include <iostream> #include <fstream> using namespace std; int main() { ifstream file; file.open("file.bin", ios::in | ios::binary); if(!file) cerr << "not able read" << endl; else { cout << "opened" << endl; int i_var; double d_var; while(!file.eof()) {...
Read more