Swift 3.0

Take a screenshot of current screen and make it blur.

//

// Helper.swift

// Blur

//

// Created by Narender Kumar on 09/10/18.

// Copyright © 2018 Appster. All rights reserved.

//

import Foundation

import UIKit

extension UIApplication {

var screenShot: UIImage? {

if let layer = keyWindow?.layer {

let scale = UIScreen.main.scale

UIGraphicsBeginImageContextWithOptions(layer.frame.size, false, scale);

if let context = UIGraphicsGetCurrentContext() {

layer.render(in: context)

let screenshot = UIGraphicsGetImageFromCurrentImageContext()

UIGraphicsEndImageContext()

return screenshot

}

}

return nil

}

}

func blurEffect(_ img: UIImage)-> UIImage {

let context = CIContext(options: nil)

let currentFilter = CIFilter(name: "CIGaussianBlur")

let beginImage = CIImage(image: img)

currentFilter!.setValue(beginImage, forKey: kCIInputImageKey)

currentFilter!.setValue(10, forKey: kCIInputRadiusKey)

let cropFilter = CIFilter(name: "CICrop")

cropFilter!.setValue(currentFilter!.outputImage, forKey: kCIInputImageKey)

cropFilter!.setValue(CIVector(cgRect: beginImage!.extent), forKey: "inputRectangle")

let output = cropFilter!.outputImage

let cgimg = context.createCGImage(output!, from: output!.extent)

let processedImage = UIImage(cgImage: cgimg!)

return processedImage

}

Full project code link

 Keyboard correct height

If you are not getting keyboard correct height and you are using below code.

Objective c
Problem : 

- (void)keyboardWillChange:(NSNotification *)notification {
    NSDictionary* keyboardInfo = [notification userInfo];
    NSValue* keyboardFrameBegin = [keyboardInfo valueForKey:UIKeyboardFrameBeginUserInfoKey];
    CGRect keyboardFrameBeginRect = [keyboardFrameBegin CGRectValue];
}

The problem is since iOS 8 this will not give the correct value, if the keyboard suggestions is up or if I push them down I get different (not correct) values.


Replace you NSValue code 
Solution 

NSValue* keyboardFrameBegin = [keyboardInfo valueForKey:UIKeyboardFrameEndUserInfoKey];

Replace occurrences of space in URL

Some time developer face issue to validate or perfect in URL below code help you create a correct URL.

I want to replace the spaces with '%20'.

The correct format for replacing space from url is :

Objective C

NSString *urlString;//your url string.

urlString = [originalUrl stringByReplacingOccurrencesOfString:@" " withString:@"%20"];

or

urlString = [originalUrl stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

iOS 9 and later

urlString = [originalUrl stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];

Swift :

var originalUrl = "https://google.co.in"
var urlString :String = originalUrl.stringByReplacingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!

ios 9 and later

var urlString :String = originalUrl.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAllowedCharacterSet())!

Swift 4

var urlString = originalString.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlQueryAllowed)

Swift 3.0  Post Local Notification

Notification name should be same for both sender and receiver

// Some where in class A [Post (Broadcast)]

let notificationObjName = Notification.Name("NotificationName")

NotificationCenter.default.post(name: notificationObjName, object: nil)

// And in other class B register for notification

let notificationName = Notification.Name("NotificationName")

NotificationCenter.default.addObserver(self, selector: #selector(ClassB.methodName), name: notificationName, object: nil)

// This method is call when post notification in Class B

func methodName(notification: NSNotification) {

        // Do, what you want

    }

Pass data using notification

let tempDict:[String: UIImage] = ["image": image]

// post a notification with data to class A

NotificationCenter.default.post(name: NSNotification.Name(rawValue: "notificationName"), object: nil, userInfo: tempDict)

        

// Register to receive notification in your class B

NotificationCenter.default.addObserver(self, selector: #selector(classB.methodName(_:)), name: NSNotification.Name(rawValue: "notificationName"), object: nil)

// recive notification

func methodName(_ notify: NSNotification) {        

    if let image = notify.userInfo?["image"] as? UIImage {

       // Do, what you want

     }

}

Swift 3.0 - Check if array contains element with property 

if array.contains(where: { $0.someProperty == "matchProperty" }) {
     // Property found
} else {
    // Property not found
}


    let elements = [1, 2, 3, 4, 5]

    if elements.contains(5) { 

        // Found

      } else {

         // Not Found

      }

If no Simulator showing in xcode try this

I could not find any solution that would fix my issue. All simulators were there for all projects but the one that I needed them.

Solution:

Build Settings -> Architectures -> Supported Platforms:

changed from iphoneos to iOS

xcode : 9.3