iOS Set Navigation Bar Back Button Title

In summary, to set the back button title of the current ViewController, we create a backBarButtonItem for the previous ViewController.

situee.blogspot.com

Config Apache SVN server for Mavericks

I have a post about Config Apache SVN server for Mountain Lion

This time, after upgrade to 10.9 Mavericks, Apache fails again.

The mod_dav_svn.so and mod_authz_svn.so are missing.

$ apachectl -S

httpd: Syntax error on line 501 of /private/etc/apache2/httpd.conf: Syntax error on line 2 of /private/etc/apache2/other/svn.conf: Cannot load /usr/libexec/apache2/mod_dav_svn.so into server: dlopen(/usr/libexec/apache2/mod_dav_svn.so, 10): image not found



Here's the fix

Download And Build Subversion

 http://archive.apache.org/dist/subversion/subversion-1.6.23.tar.bz2


add symlink

ln -s /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain /Applications/Xcode.app/Contents/Developer/Toolchains/OSX10.9.xctoolchain

cd subversion-1.6.23
./configure
make
sudo cp subversion/mod_dav_svn/.libs/mod_dav_svn.so /usr/libexec/apache2/.
sudo cp subversion/mod_authz_svn/.libs/mod_authz_svn.so /usr/libexec/apache2/.

Download previous versions Titanium Studio

Links to download previous versions Appcelerator Titanium Studio.

Cannot find the version you want in the following links?
Check this http://builds.appcelerator.com.s3.amazonaws.com/index.html

The latest version is here
http://titanium-studio.s3.amazonaws.com/latest/Titanium_Studio.dmg

Titanium Studio 3.2.3

• OS X Installer
• Windows Installer
• Linux 32-bit Installer
• Linux 64-bit Installer

Titanium Studio 3.2.0

• OS X Installer
• Windows Installer
• Linux 32-bit Installer
• Linux 64-bit Installer

Titanium Studio 3.1.3

• OS X Installer
• Windows Installer
• Linux 32-bit Installer
• Linux 64-bit Installer

iOS define local and global NSString constant

situee.blogspot.com

1. Local Constant

There are two type of constants.

(1)  static NSString * const kMyConstant = @"constant string";

(2)  #define kMyConstant @"constant string"


"static const" is a better way, although "#define" is much shorter,

Here are some reasons:

• "#define" are not type-safe. 
• We can test the value of the "static const" constant with debugger;
• Memory. Preprocessor create a new string each time the macro appear, while "static const" reuse the same string.

2. Global Constant

----------------  .h file  --------------

extern NSString *const kMyConstant;

----------------  .m file  --------------
// define in a .m file OUTSIDE @implementation like...

NSString *const kMyConstant = @"my constant";

The extern declaration says that there exists an NSString * const by the name kMyConstant whose storage is created in some other place.[1]

Remove the static -- that specifies that kMyConstant is only visible in files linked with this one.[1]

C pointer and constant

Review C pointer and constant:
situee.blogspot.com

1. Pointer to Constant Value

const char *ptr = 'a';  OR    char const *ptr = 'a'; 

"const" precedes the *, that means the pointer treat *ptr  as constant

This is NOT valid     :  
*ptr = 'b';

Another example;

int nValue = 5;
const int *pnPtr = &nValue;

Thus, the following is okay:
    nValue = 6; // nValue is non-const
But the following is not:
    *pnPtr = 6; // pnPtr treats its value as const

2. Constant Pointer

char * const ptr = 'a';

This means the pointer ptr is a constant pointer

This is NOT valid:
char char_B = 'b';
ptr = &char_B;

3. Constant Pointer to Constant Value

const char * const ptr = 'a';  OR    char const * const ptr = 'a';

Reference:

http://www.learncpp.com/cpp-tutorial/610-pointers-and-const/
http://www.cprogramming.com/reference/pointers/const_pointers.html
http://www.noxeos.com/2011/07/29/c-const-static-keywords/
http://www.codeguru.com/cpp/cpp/cpp_mfc/general/article.php/c6967/Constant-Pointers-and-Pointers-to-Constants.htm

Android - SuppressLint cannot be resolved to a type

After upgrading my Android SDK 20 and ADT-23.0.2, some projects got error "SuppressLint cannot be resolved to a type"

I fixed this by

1. In project property -> Android, change to another API level and change back.
2. change the order in project property ->Java build path -> Order and Export.
3. also please try refresh and clean the project.

Hope it can help and save some hours.

OpenDrive cloud storage direct link

I am trying OpenDrive storage service.
You will get 5G storage, and 1G traffic for a basic account.
It is great that you can share file by direct link.
I think it is very useful for a developer.
We can put XML, JSON, image files on the OpenDrive for testing.

Go to their website and have a look:
www.opendrive.com

Setup DNSmasq MAC DNS server

$ brew install dnsmasq

$ cp /usr/local/opt/dnsmasq/dnsmasq.conf.example /usr/local/etc/dnsmasq.conf
$ sudo cp -fv /usr/local/opt/dnsmasq/*.plist /Library/LaunchDaemons
$ sudo launchctl load /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist

Go to System Network preference,
Set the only one DNS as 127.0.0.1

/usr/local/etc/dnsmasq.conf

#upstream dns servers
resolv-file=/etc/resolv.dnsmasq.conf

#for the host domain to the ip, like the "hosts" file
address=/dev/127.0.0.1
address=/double-click.net/127.0.0.1

# set listen address as your IP
listen-address=127.0.0.1, 192.168.11.12

/etc/resolv.dnsmasq.conf  

Put upstream server in /etc/resolv.dnsmasq.conf , such as 8.8.8.8
nameserver upstream_dns_server
nameserver 8.8.8.8


Kill the process, it will restart and reload new config.

$ sudo kill $(ps aux | grep '[d]nsmasq' | awk '{print $2}')


Reference:

Install DNSmasq locally on Mac OS X via Homebrew
http://blog.philippklaus.de/2012/02/install-dnsmasq-locally-on-mac-os-x-via-homebrew/

Setup a wildcard TLD using Dnsmasq on OS X
http://bhamrick.com/2013/04/18/setup-a-wildcard-tld-using-dnsmasq-on-os-x/

https://gist.github.com/g3d/2709563

http://unixhelp.ed.ac.uk/CGI/man-cgi?ps

Appendix:

 ps aux  : to see every process on the system using bSD syntax;

$ ps aux 
USER       PID  %CPU %MEM  VSZ RSS     TTY   STAT START   TIME COMMAND
timothy  29217  0.0  0.0 11916 4560 pts/21   S+   08:15   0:00 pine 
root     29505  0.0  0.0 38196 2728 ?        Ss   Mar07   0:00 sshd: can [priv]  
can      29529  0.0  0.0 38332 1904 ?        S    Mar07   0:00 sshd: can@notty 
USER = user owning the process
PID = process ID of the process
%CPU = It is the CPU time used divided by the time the process has been running.
%MEM = ratio of the process’s resident set size to the physical memory on the machine
VSZ = virtual memory usage of entire process
RSS = resident set size, the non-swapped physical memory that a task has used
TTY = controlling tty (terminal)
STAT = multi-character process state
START = starting time or date of the process
TIME = cumulative CPU time
COMMAND = command with all its arguments
ps -aux VS ps aux

Note that "ps -aux" is distinct from "ps aux". The POSIX and UNIX standards require that "ps -aux" print all processes owned by a user named "x", as well as printing all processes that would be selected by the -a option. If the user named "x" does not exist, this ps may interpret the command as "ps aux" instead and print a warning. This behavior is intended to aid in transitioning old scripts and habits. It is fragile, subject to change, and thus should not be relied upon.