launch safari from iOS app

Objective C:
if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:@"link://"]]){
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"link://"]];
}

openURL Deprecated in iOS10:
openURL:
A way to open external links
canOpenURL:
Got some privacy controls in iOS 9 to stop you from querying devices for installed apps.

Now with iOS 10 openURL:options:completionHandler: is used instead of openURL

Objective C:
Handle completionHandler:
- (void)openScheme:(NSString *)scheme {
UIApplication *application = [UIApplication sharedApplication];
NSURL *URL = [NSURL URLWithString:scheme];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:^(BOOL success) {
NSLog(@"Open %@: %d",scheme,success);
}];
} else {
BOOL success = [application openURL:URL];
NSLog(@"Open %@: %d",scheme,success);
}
}

Without handling completionHandler:
[application openURL:URL options:@{} completionHandler:nil];

Swift 3.0:
func open(scheme: String) {
if let url = URL(string: scheme) {
if #available(iOS 10, *) {
UIApplication.shared.open(url, options: [:], completionHandler: {
(success) in print("Open \(scheme): \(success)")
})
} else {
let success = UIApplication.shared.openURL(url)
print("Open \(scheme): \(success)")
}
}
}


Options: UIApplicationOpenURLOptionUniversalLinksOnly

Use a boolean value set to true (YES) to only open the URL if it is a valid universal link with an application configured to open it.

If there is no application configured or the user disabled using it to open the link the completion handler is called with false (NO).

Objective C:
NSDictionary *options = @{UIApplicationOpenURLOptionUniversalLinksOnly : @YES};
[application openURL:URL options:options completionHandler:nil];

Swift:
let options = [UIApplicationOpenURLOptionUniversalLinksOnly : true]
UIApplication.shared.open(url, options: options, completionHandler: nil)

isKindOfClass

In Cocoa, almost all classes inherit from NSObject.

That means that NSObject is ‘the superclass’, and (almost) the rest of the classes are subclasses of NSObject.

isKindOfClass:
Returns a Boolean value that indicates whether the receiver is an instance of given class or an instance of any class that inherits from that class.

Objective C:
if ([element isKindOfClass:[UIImageView class]]){
}

or

NSArray *viewControllers = [self.navigationController viewControllers];
for (id aViewController in viewControllers) {
if([aViewController isKindOfClass:[TestViewController class]]){
print(aViewController)
return;//return for stop the loop
}
}

Swift:

if (element is UIImageView) {
}

or

let viewControllers: [UIViewController] = (self.navigationController?.viewControllers)! as [UIViewController];
for aViewController:UIViewController in viewControllers {
if aViewController.isKind(of: TestViewController.self) {
print(aViewController)
return //return for stop the loop
}
}

REMOVE ALL SUBVIEWS

Objective C:
To remove all subViews

[self.view.subviews makeObjectsPerformSelector: @selector(removeFromSuperview)];

# pragma mark - Removing all subviews
- (void) clearAction{
NSLog(@"clear all subViews");
[self.view.subviews makeObjectsPerformSelector: @selector(removeFromSuperview)];
}
or
# pragma mark - Removing all subviews
- (void) clearAction{
for (UIView *subview in self.view.subviews){
[subview removeFromSuperview];
}
}


To remove particular subview
[subview removeFromSuperview];

Swift 3.0:
To remove all subViews

//MARK: Removing all subviews
func clearAction() {
self.view.subviews.forEach { subview in
subview.removeFromSuperview()
}
}
or
//MARK: Removing all subviews
func clearAction() {
for subView in self.view.subviews {
subView.removeFromSuperview()
}
}


To remove particular subview
subView.removeFromSuperview()

Parse JSON data from local file

JSON – JavaScript Object Notation.

JSON is a text-based, lightweight, human-readable, easy way for storing and exchanging data.

Objective c:


# pragma mark - JSON Serial from local file
-(void) jsonSerial{
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"fileName" ofType:@"json"];
NSData *data = [NSData dataWithContentsOfFile:filePath];
NSArray *jsonData = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil];
for (id jsonObject in jsonData){
NSLog(@"\nName-->%@", [jsonObject valueForKey:@"key"]);
}
}

Swift 2.0:


// MARK: JSON Serial from local file
func jsonSerial(){
do{
let filePath = NSBundle.mainBundle().pathForResource("fileName", ofType: "json")
let data = NSData(contentsOfFile: filePath!)
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: .AllowFragments) as! [[String : String]]
for item in json{
print(item["key"]!)
}
} catch let error {
print("json error: \(error)")
}
}


Swift 3.0:


// MARK: JSON Serial from local file
func jsonSerial() {
let data = try? Data(contentsOf: URL(fileURLWithPath: Bundle.main.path(forResource: "fileName", ofType: "json")!))
do {
let parsedObject = try JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.allowFragments)
for item in parsedObject as! [[String : String]] { //[String : String] type of json content
print(item["key"]!)
}
}catch{
print("not able to parse")
}
}