Wednesday 28 October 2015

UIImage Category( Resize+RoundCourner+Alpha) Swift version

For iOS developer, Resizing images, cropping them to a specific thumbnail size, applying rounded corners is extremely easy with Trevor Harmon’s Image categories UIImage Category. These category helped many developers to finish image implementation quickly and very easily in their projects.

After apple announcement, "Swift will become a successor of objective -C", mostly iOS app developer switching their development in swift language. As Trevor Harmon’s Image categories are written in Objective-C, so developer chose bridging concept to use these category features in the swift code.

Nowadays people bypass a bridging headache as they like to complete their whole project in Swift. It will be helpful for them if they found the category in swift so that they can easily use it and finish their projects within deadline with a smiling face. 

I have created a swift version of Trevor Harmon’s Image categories found in a Blog.  Also, I have added some new methods and extra features. Here is the link of Github of these category files.

https://github.com/Rupesh17/UIImage-Category-Swift

You can download them, use them directly without bridging headache like Objective-C version.

Modification or suggestion will be helpful to make it best.  In case, of any question or suggestion feel free to ask. Also, If you want any other helpful objective -C code in swift, let me know.




Tuesday 29 September 2015

App Transport Security (ATS) and iOS 9 HTTP Connection error "The operation couldn’t be completed"

In 2015, With the launch of iOS 9 and OSX  El Capitan apple disabled all unsecured HTTP traffic from iOS apps and comes with new privacy feature called App Transport Security (ATS) to enforce best practices in secure connections between an app and its back end.

All iOS 9 devices running apps built with Xcode 7 that don’t disable ATS will be affected by this change and if app try to make HTTP requests with ATS enabled (iOS 9 and above), we will see the errors like this:

Error Domain=NSURLErrorDomain Code=-1004 "Could not connect to the server." UserInfo=0x12ed5bad0 {NSUnderlyingError=0x12ee495b0 "The operation couldn’t be completed. (kCFErrorDomainCFNetwork error -1004.)"

OR

NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9802)

Before finding the solution to resolve this error we should know about ATS and why apple recommend this .

What is ATS and Why Apple pushing it as default from iOS 9?

According to apple “ App Transport Security (ATS) lets an app add a declaration to its Info.plist file that specifies the domains with which it needs secure communication. ATS prevents accidental disclosure, provides secure default behavior, and is easy to adopt. You should adopt ATS as soon as possible, regardless of whether you’re creating a new app or updating an existing one.

If you’re developing a new app, you should use HTTPS exclusively. If you have an existing app, you should use HTTPS as much as you can right now, and create a plan for migrating the rest of your app as soon as possible.“

Simply, App Transport Security is a feature that improves the security of connections between an app and web services. The feature consists of default connection requirements that conform to best practices for secure connections.

The reason why Apple is pushing so aggressively to force secure connections is because it’s the right thing to do. Protecting personal data from being compromised over insecure wireless connections, among other things, is great for users.


Requirement to adopt ATS :

App Transport Security is enabled by default when using NSURLSession, NSURLConnection, or CFURL in iOS 9 or OS X El Capitan.

App Transport Security requirements:

 * The server must support at least Transport Layer Security (TLS) protocol version 1.2.

 * Connection ciphers are limited to those that provide forward secrecy (see the list of ciphers below.)

 * Certificates must be signed using a SHA256 or greater signature hash algorithm, with either a 2048-bit or greater RSA key or a 256-bit or greater Elliptic-Curve (ECC) key.Invalid certificates result in a hard failure and no connection.


If your application attempts to connect to any HTTP server that doesn’t support the latest SSL technology (TLSv1.2), your connections will fail with an error like this:

Error Domain=NSURLErrorDomain Code=-1004 "Could not connect to the server." UserInfo=0x12ed5bad0 {NSUnderlyingError=0x12ee495b0 "The operation couldn’t be completed. (kCFErrorDomainCFNetwork error -1004.)"

OR

App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.


How to Bypass App Transport Security:

ATS is good for you and your users and you shouldn’t disable it, but there are the way for developers to override this default behavior and turn off transport security as per the app requirement. To disable ATS you need to Open Info.plist, and add the following lines:

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSAllowsArbitraryLoads</key>
    <true/>
</dict>


Your info.plist must be look like this.




Per-Domain Exceptions:

You can opt-out of ATS for certain URLs in your Info.plist by using NSExceptionDomains. Within the NSExceptionDomains dictionary you can explicitly define URLs that you need exceptions for with ATS.

Add this code to your info.plist source file.


<key>NSAppTransportSecurity</key>
    <dict>
        <key>NSExceptionDomains</key>
        <dict>
            <key>server1.com</key>
            <dict>
                <!--Include to allow subdomains-->
                <key>NSIncludesSubdomains</key>
                <true/>
                <!--Include to allow HTTP requests-->
                <key>NSExceptionAllowsInsecureHTTPLoads</key>
                <true/>
                <!--Include to specify minimum TLS version-->
                <key>NSExceptionMinimumTLSVersion</key>
                <string>TLSv1.1</string>
            </dict>
            <key>server2.com</key>
            <dict>
                <!--Include domain support forward secrecy using ciphers-->
                <key>NSExceptionRequiresForwardSecrecy</key>
                <true/>
                <!--Include to allow HTTP requests-->
                <key>NSExceptionAllowsInsecureHTTPLoads</key>
                <false/>
            </dict>
        </dict>
    </dict>

Your structured info.plist source file looks like this.



And your info.plist looks like this :




Now, You can see ATS is good for app developers and app users as it improves the security of connections between an app and web services, but you can override it.

Tuesday 4 August 2015

AppleScript: Variables, Operators and useful command


In our last blogs "Introduction to AppleScript" and "Getting Started with Apple Script", we discussed what is apple script, how it's useful for Mac users & how to write some basic script. Now it's time to go in deep and learn how to use variable, operators and more useful command.

Variables, Operators and useful command


Declaring Variables:

Variables are basically a way to store information within your script. You can, for example, do a calculation and save the result in a variable.It allows you to access that information later without doing the calculation again.

In AppleScript variables are declared using the "set" and "to" commands. set is the keyword that you use to define a variable. The syntax goes like this:

Format:     set variableName to "variableValueOrData"

Example:   set userFullName to "Rupesh Kumar"

By doing this you are setting your variable name. Many programming languages require that you state the type of variable you want in the declaration (integer, floating point, text, etc.). AppleScript however, is intelligent enough to work with your variables without any instruction about the format.

The most common data types used in AppleScript are numbers, string or text, lists,boolean,records.

string: Stores a string of characters of unlimited length. You define a string by bracketing a quantity between double-quotes:

set myString to "hello world"

You must escape the double-quote and the backslash with backslash.
set myString to "escape \" and \\ with \\"
AppleScript defines several constants of class string: return, space and tab.

boolean: true or false

integer: Stores integers in the range -536870912 .. 536870911

real: Stores (in double-precision) a real number in the range ±10^308.

date: Stores a date.

list: Stores a list of any quantities. You define a list by bracketing its items between braces.the syntax for defining a list variable goes like this: {data,data}. Text has quotes around it as usual. You can retrieve a particular list item by using the item number of listVariable syntax. The first item of the list is item 1. You can add things to the end of a list by using the concatenation operation (with the &).

set names to {"Ritesh", "Rupesh", "Amit"}
log item 2 of names
set names to names & "Rohit"
log names

record - stores a list of key-value pairs. you can access the record using it key.

set the_record to {firstname:"Rupesh", lastname:"Kumar"}
log lastname of the_record
-- kumar


How to add comments in apple Script:

In AppleScript, comment is a text inside the editor that it is ignored by the script and only there for humans to read. Comments are used to annotate the code and remind us what each operation, variable ,func, logic does.

You can add comment in applescript by adding the “—-”. For example:

Syntax:
script code —-Your comment

set name to "Rupesh" ---here we set the text Rupesh to variable name.

The gray text you see in the end of line after —- is the comment.


Some Useful Commands:

activate command:
Brings an application to the front, and opens it if it is on the local computer and not already running.

activate application "TextEdit"
OR
tell application "TextEdit" to activate


launch command:
Launches an application, if it is not already running, but does not send it a run command.
If an application is already running, sending it a launch command has no effect.

launch application "TextEdit"
or
tell application "TextEdit" to launch

display notification command:

Posts a notification using the Notification Center, containing a title, subtitle, and explanation, and optionally playing a sound.

Parameters
text:The body text of the notification. At least one of this and the title must be specified.
with title: The title of the notification. At least one of this and the body text must be specified.
subtitle text: The subtitle of the notification.
sound name text: The name of a sound to play when the notification appears. This may be the base name of any sound installed in Library/Sounds.text

Example:

display notification "It's time to go for lunch" with title "Rupesh Script classes" subtitle "Lunch Time"

copy command:
Copies one or more values, storing the result in one or more variables. This command only copies AppleScript values, not application-defined objects.

The copy command may be used to assign new values to existing variables, or to define new variables.
The copy is a “deep” copy, so sub-objects, such as lists within lists, are also copied.

set Fname to "Rupesh "
set Lname to "Kumar"
copy Fname to Lname
display dialog Fname & Lname

delay command
Waits for a specified number of seconds.
example

tell application “Finder” to activate
delay 2.0
end tell

Operator in AppleScript:

Arithmetic operators: Arithmetic operation can be applied on numbers only.

  + operator  example: log numberA + numberB —-Addition
  - operator  example: log numberA - numberB —-subtraction
  * operator  example: log numberA * numberB —-multiplication
  / operator  example: log numberA / numberB —-division (result will be a real)
  ^ operator  example: log numberA + numberB —- raise a number to a power
div operator  example: log numberA div numberB —- Division (Result will be an integer)

Relational operators: Relational operators can be applied for both number and string. In string operators work on the bases of string length. Only is equal to(=) operator can be applied on any data type & compare the inside data.

 > operator     example: log numberA > numberB       -- is greater than
 < operator     example: log "Rupesh" < "Rupe"          --is less than (False: based on string length)
  >= operator  example: log numberA >= numberB    --is greater than or equal to
  <= operator  example: log "Rupesh" <= "rupesh"     --is less than or equal to (based on string length)

equal, is not equal to:
We mostly use equal, is not equal to operators for numbers, list, record, and text comparison.lets see how it’s work for them in apple script.

numbers: 
Two number are equal if their real value is equal.

Example: log 55 = 55.1 -- result will be false
                log 55 = 55.0  -- result will be true
list:
Two lists are equal if they both contain the same number of items and if the value of an item in one list is identical to the value of the item at the corresponding position in the other list:

{ 1, 2, “Hi” } = {1, 2, “bye”} --result: false

record:
Two records are equal if they both contain the same collection of properties and if the values of properties with the same label are equal. The order in which properties are listed does not affect equality.

{ name:”Rupesh”, age:”24” } = { age:”24”, name:”Rupesh”}  —-result : true

Text:
Two text objects are equal if they are both the same series of characters. They are not equal if they are different series of characters.

"RUpesh" is equal to "rupesh" --result: true

considering case
"RUpesh" is equal to "rupesh"

end considering

concatenation( &):
The process of combining two pieces of text is called a concatenation operation. In AppleScript, you do this with the ampersand symbol. In appleScript & (concatenation) operation be done with string,list,record.

Example:

String concatenation:

set textA to "Hello"
set textB to " Apple"
log textA & textB

list concatenation

set names to {"Ritesh", "Rupesh", "Amit"}
log item 2 of names
set names to names & "Rohit"
log names

Same you can do with record also.

Where, I can found more command:
AppleScript itself has a wide range of commands that can be applied to any program or item in OS X. For each application there are manuals for how to communicate with those applications through AppleScript. These manuals are called "Dictionaries".

To view a dictionary, go to File>Open Dictionary in Script Editor. Scroll down the list of applications, click on any application and hit "OK".  For example, I select iTunes app and click on “OK”. You should see the following window:





The column on the left contains the available "Suites" of commands and items. When you click on a suite, you'll see everything contained in the suite displayed below.




Suites contain commands (C with a circle) and classes (C with a square), classes contain properties (P) and elements (E).



Now, use your smartness and create your own script.