How to display image from url in swift - ios

I'm making an async call which the JSON response contains both text and url to images that I want to display in a UIImageView. Now displaying the text in a label isn't the problem but loading the images is giving me hard times. Have shared my code below.
//Declared variables to hold response
var offerContent: String?
var offerImage: URL?
var offerTitle: String?
var suggestionLabel:String?
var suggestionScreen: String?
//create a task to send reques
let task = URLSession.shared.dataTask(with: request as URLRequest){
data, response, error in
if error != nil {
print("error is:: \(error!.localizedDescription)")
return;
}
//parsing the response
do {
// converting response to NSDictionary
let myJSON = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSDictionary
DispatchQueue.main.async {
if let parseJSON = myJSON{
var responseCode: Int!
var responseMessage: NSArray!
//getting the json response
responseCode = parseJSON["RESPONSECODE"] as! Int?
responseMessage = parseJSON["RESPONSEMESSAGE"] as! NSArray?
if responseCode == 0 {
for obj in responseMessage{
if let dict = obj as? NSDictionary{
self.offerContent = dict.value(forKey: "CONTENT") as? String
self.offerTitle = dict.value(forKey: "TITLE") as? String
self.suggestionLabel = dict.value(forKey: "SUGGESTION_LABEL") as? String
self.suggestionScreen = dict.value(forKey: "SUGGESTION_SCREEN") as? String
self.offerImage = dict.value(forKey: "IMAGE") as? URL
// print("image:: \(self.offerImage!)")
let offerImageView = UIImageView()
self.darkView.addSubview(offerImageView)
offerImageView.heightAnchor.constraint(equalToConstant: 30).isActive = true
offerImageView.widthAnchor.constraint(equalTo: self.darkView.widthAnchor).isActive = true
offerImageView.topAnchor.constraint(equalTo: self.darkView.topAnchor, constant: 20).isActive = true
offerImageView.image = UIImage(data: self.offerImage)
}
}
}
print(parseJSON)
}
}
}catch{
print("catch:: \(error.localizedDescription)")
}
}
task.resume()

Try this code.
let url = URL(string: "IMAGE URL HERE")
let data = try? Data(contentsOf: url)
if let imageData = data {
let image = UIImage(data: imageData)
}

Import and use Kingfisher
self.imageview.kf.setImage(with: "url")

Related

JSON Parsing Swift using JSONPlaceholder

I'm playing with Swift and JSONPlaceholder. I want to retrieve all the data contained in: https://jsonplaceholder.typicode.com/photos
I created a function that is acceding to the url, downloading the JSON but then I don't know how can I obtain the title and the thumbnailUrl to pass then for populate the tableView. In the past I used this code but now it's not working because on the JSONPlaceholder there are no array.
Any help for re-arrange the code for read and obtain the jsonplaceholder elements?
func loadList(){
let url = URL(string: urlReceived)
var myNews = NewInfo()
let task = URLSession.shared.dataTask(with: url!) {
(data, response, error) in
if error != nil{
print("ERROR")
}
else{
do {
if let content = data{
let myJson = try JSONSerialization.jsonObject(with: content, options: .mutableContainers)
//print(myJson)
if let jsonData = myJson as? [String : Any] {
if let myResults = jsonData["list"] as? [[String : Any]]{
//dump(myResults)
for value in myResults{
//Read time string from root
if let time = value ["dt_txt"] as? String{
myNews.time = time
}
//Read main container
if let main = value["main"]
as? [String : Any]{
if let temperature = main["temp"] as? Double {
myNews.temperature = String(temperature)
}
}
//Read from weather container
if let weather = value["weather"] as? [[String: Any]]{
for value in weather{
if let weatherContent = value["description"] as? String{
myNews.weatherDescription = weatherContent
}
}
}
self.myTableViewDataSource.append(myNews)
}
dump(self.myTableViewDataSource)
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}
}
}
catch{
}
}
}
task.resume()
}//End func
Okey, so with Alamofire + SwiftyJSON, you can do this:
func loadList(){
let url = "https://jsonplaceholder.typicode.com/photos"
AF.request(url).responseJSON { (response) in
switch response.result {
case .success(let value):
let json = JSON(value)
print(json)
for value in json.arrayValue {
let url = value.dictionaryValue["url"]!.stringValue
let albumId = value.dictionaryValue["albumId"]!.stringValue
let thumbnailUrl = value.dictionaryValue["thumbnailUrl"]!.stringValue
let id = value.dictionaryValue["id"]!.stringValue
let title = value.dictionaryValue["title"]!.stringValue
// Add this album to array.
let album = AlbumModel(id: id, albumId: albumId, title: title, thumbnailUrl: thumbnailUrl)
albums.append(album)
}
case .failure(let error):
print(error)
}
}
}
EDIT:
I made model for values
class AlbumModel {
var id: String?
var albumId: String?
var title: String?
var thumbnailUrl: String?
init(id: String?, albumId: String?, title: String?, thumbnailUrl: String?){
self.id = id
self.albumId = albumId
self.title = title
self.thumbnailUrl = thumbnailUrl
}
}
After that, just create an array like var albums = [AlbumModel]() and you can append all the albums to this. Easy to use after in tableViewcell (example: albums[indexPath.row].id)

Swift JSON parsing and printing a specified value from an array

Hi I'm trying to get data from a certain JSON API. I can gat a snapshot of all values from the API, which is shown below. But I can't manage to put a specifiek row in a variable. This is the JSON form which I get. I want to print the "Description" value.Can someone help me with this?
And Hier is my code:
func apiRequest() {
let config = URLSessionConfiguration.default
let username = "F44C3FC2-91AF-5FB2-8B3F-70397C0D447D"
let password = "G23#rE9t1#"
let loginString = String(format: "%#:%#", username, password)
let userPasswordData = loginString.data(using: String.Encoding.utf8)
let base64EncodedCredential = userPasswordData?.base64EncodedString()
let authString = "Basic " + (base64EncodedCredential)!
print(authString)
config.httpAdditionalHeaders = ["Authorization" : authString]
let session = URLSession(configuration: config)
var running = false
let url = NSURL(string: "https://start.jamespro.nl/v4/api/json/projects/?limit=10")
let task = session.dataTask(with: url! as URL) {
( data, response, error) in
if let taskHeader = response as? HTTPURLResponse {
print(taskHeader.statusCode)
}
if error != nil {
print("There is an error!!!")
print(error)
} else {
if let content = data {
do {
let array = try JSONSerialization.jsonObject(with: content, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject
print(array)
if let items = array["items"] {
if let description = items["Description"] as? [[String:Any]]{
print(description as Any)
}
}
}
catch {
print("Error: Could not get any data")
}
}
}
running = false
}
running = true
task.resume()
while running {
print("waiting...")
sleep(1)
}
}
First of all the array is not an array and not AnyObject, it's a dictionary which is [String:Any] in Swift 3.
let dictionary = try JSONSerialization.jsonObject(with: content) as! [String:Any]
print(dictionary)
I don't know why all tutorials suggest .mutableContainers as option. That might be useful in Objective-C but is completely meaningless in Swift. Omit the parameter.
The object for key itemsis an array of dictionaries (again, the unspecified JSON type in Swift 3 is Any). Use a repeat loop to get all description values and you have to downcast all values of a dictionary from Any to the expected type.
if let items = dictionary["items"] as? [[String:Any]] {
for item in items {
if let description = item["Description"] as? String {
print(description)
}
}
}
Looks like items is an array that needs to be looped through. Here is some sample code, but I want to warn you that this code is not tested for your data.
if let items = array["items"] as? [[String: AnyObject]] {
for item in items {
if let description = item["Description"] as? String{
print("Description: \(description)")
}
}
}
This code above, or some variation of it, should get you on the right track.
use the SwiftyJSON and it would be as easy as json["items"][i].arrayValue as return and array with items Values or json["items"][i]["description"].stringValue to get a string from a row

Saving to Parse in a while loop swift

So I have a problem where I call save after putting some items in an object. I go to an API and I download some info and then I save it to another system for temporary use, however the .save() seems to only save 2 items, with no special pattern in which it selects. Can someone explain what the problem is?
let url = URL(string: link)
let spots = PFObject(className:"spot")
let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
if error != nil {
print(error)
}
else{
if let urlContent = data{
do{
let jsonResult = try JSONSerialization.jsonObject(with: urlContent, options: JSONSerialization.ReadingOptions.mutableContainers)
let results = (jsonResult as! NSDictionary)["results"]
let venueList = (results as! NSArray)
//print(jsonResult)
var i = 0
while i < venueList.count{
let venues = venueList[i] as! NSDictionary
let name = venues["name"] as! String
let geometry = venues["geometry"] as! NSDictionary
let location = geometry["location"] as! NSDictionary
let cLat = location["lat"] as! Double
let cLon = location["lng"] as! Double
let vPoint = PFGeoPoint(latitude: cLat, longitude: cLon)
//print(name," ", vPoint)
spots["venue"] = name
spots["name"] = vPoint
do{
try HotSpots.save()
print("Saved! ",name," ", vPoint)
}
catch{
print("Save Error")
}
i+=1
}
}
catch{
print("JSON Error")
}
}
}
}
task.resume()
}
The issue is that you're saving the two values always in the same PFObject instance.
Move the line let spots = PFObject(className:"spot") in the loop.
PS: Use Swift native types. For example this is more efficient
let location = geometry["location"] as! [String:Double]
let cLat = location["lat"]!
let cLon = location["lng"]!

NSURLSession.sharedSession().dataTaskWithRequest runs slow in function

My problem arises when I want to populate data from my mysql database into a class object. I am trying to return an array of objects and it returns nil and then it fills itself somehow. How can I make it fill before returning the blank array?
Here is my code and a screenshot of code output
import Foundation
class Research
{
var mainResearchImageURL:String = ""
var userProfileImageURL:String = ""
var caption:String = ""
var shortDescription:String = ""
init(mainResearchImageURL :String, userProfileImageURL:String, caption:String, shortDescription:String)
{
self.mainResearchImageURL = mainResearchImageURL
self.userProfileImageURL = userProfileImageURL
self.caption = caption
self.shortDescription = shortDescription
}
class func downloadAllResearches()->[Research]
{
var researches = [Research]()
let urlString = "http://localhost/test/index.php"
let request = NSMutableURLRequest(URL: NSURL(string: urlString)!)
request.HTTPMethod = "POST"
let postString = "action=listresearches"
request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request, completionHandler: {data, response, error in
if (error == nil) {
do {
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as? NSArray
//let dictionary = json!.firstObject as? NSDictionary
var counter:Int = 0;
for line in json!{
let researchData = line as! NSDictionary
let researchLineFromData = Research(mainResearchImageURL: researchData["research_mainImageURL"] as! String, userProfileImageURL: researchData["research_creatorProfileImageURL"] as! String, caption: researchData["research_caption"] as! String, shortDescription: researchData["research_shortDescription"] as! String)
researches.append(researchLineFromData) //researches bir dizi ve elemanları Research türünde bir sınıftan oluşuyor.
counter += 1
print ("counter value \(counter)")
print("array count in loop is = \(researches.count)")
}
}catch let error as NSError{
print(error)
}
} else {
print(error)
}})
task.resume()
print("array count in return is = \(researches.count)")
return researches
}
}
And this is the output:
add this on you completionHandler ( it works if you update a view)
dispatch_async(dispatch_get_main_queue(), {
if (error == nil) { ...... }
})
Advice 1:
return the task and use a completion param in your method,
you can cancel the task if it's too slow.
Advice 2 :
Use alamofire and swiftyJson framework
What happen here is that you are returning the value before finish (remember that the call is Asynchronous), you can make something like this:
class func downloadAllResearches(success:([Research])->Void,failure:(String)->Void)
{
var researches = [Research]()
let urlString = "http://localhost/test/index.php"
let request = NSMutableURLRequest(URL: NSURL(string: urlString)!)
request.HTTPMethod = "POST"
let postString = "action=listresearches"
request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
let task = NSURLSession.sharedSession().dataTaskWithRequest(request, completionHandler: {data, response, error in
if (error == nil) {
do {
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as? NSArray
//let dictionary = json!.firstObject as? NSDictionary
var counter:Int = 0;
for line in json!{
let researchData = line as! NSDictionary
let researchLineFromData = Research(mainResearchImageURL: researchData["research_mainImageURL"] as! String, userProfileImageURL: researchData["research_creatorProfileImageURL"] as! String, caption: researchData["research_caption"] as! String, shortDescription: researchData["research_shortDescription"] as! String)
researches.append(researchLineFromData) //researches bir dizi ve elemanları Research türünde bir sınıftan oluşuyor.
counter += 1
print ("counter value \(counter)")
print("array count in loop is = \(researches.count)")
}
success(researches)
}catch let error as NSError{
print(error)
failure("Can be extract from NSERROR")
}
} else {
print(error)
failure("Error - Can be extract for NSERROR")
}})
task.resume()
}
And for call this Fuction use something like this:
Research.downloadAllResearches({ (objects:[Research]) -> Void in
dispatch_async(dispatch_get_main_queue(), { () -> Void in
//Do whatever you like with the content
})
}) { (failureLiteral:String) -> Void in
}

Json parsing in iOS playground do method is not parsing

I am trying to parse some json data into three different arrays based off the label in the json. I seem to be stuck and don't know why my for loop is never being entered. I am new to iOS and am using this to learn swift. Any help will be appreciated.
Here is the code that I am using:
var myPicture = [String]()
var myPath = [String]()
var mylabel = [String]()
let jsonString = "[{\"picture\" : \"Picture 1 \", \"path\": \"Path 1\" , \"label\" : \"Label 1\"}]"
//Convert jsonString to NSData
let myData = jsonString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!
do{
let promoJson = try NSJSONSerialization.JSONObjectWithData(myData, options:.AllowFragments)
if let promtions = promoJson[""] as? [[String: AnyObject]] {
for promtions in promtions {
if let picture = promtions["picture"] as? String
{
myPicture.append(picture)
if let path = promtions["path"] as? String
{
myPath.append(path)
if let label = promtions["label"] as? String
{
mylabel.append(label)
}
}
}
}
}
}catch {
print("Error with Json: \(error)")
}
print(myPicture.first)
print(myPath.first)
print(mylabel.first)
The results for the print are all nil. So nothing is being appended to the arrays
The if let promtions = promoJson[""] part won't work and would be useless anyway. This is only promoJson that you have to cast to an array of dictionaries.
You weren't that far from the solution, look at my working version of your code:
do {
let promoJson = try NSJSONSerialization.JSONObjectWithData(myData, options: [])
if let promtions = promoJson as? [[String: AnyObject]] {
for promtion in promtions {
if let picture = promtion["picture"] as? String {
myPicture.append(picture)
}
if let path = promtion["path"] as? String {
myPath.append(path)
}
if let label = promtion["label"] as? String {
mylabel.append(label)
}
}
}
} catch let error as NSError {
print(error.debugDescription)
}
Alternative
Now that the issue is resolved, let me suggest you another way: instead of separate arrays for your data, use one array of objects holding your data.
For example, make a struct like this:
struct Promotion {
let picture: String
let path: String
let label: String
}
And an array for instances of this struct:
var myPromotions = [Promotion]()
Now we can decode the JSON, create objects from it then store them in the array:
do {
let promoJson = try NSJSONSerialization.JSONObjectWithData(myData, options: [])
if let promtions = promoJson as? [[String: AnyObject]] {
for promtion in promtions {
if let picture = promtion["picture"] as? String,
path = promtion["path"] as? String,
label = promtion["label"] as? String {
let promo = Promotion(picture: picture, path: path, label: label)
myPromotions.append(promo)
}
}
}
} catch let error as NSError {
print(error.debugDescription)
}
Now look at the content of the array, very convenient:
for promo in myPromotions {
print(promo.label)
print(promo.path)
print(promo.picture)
}
When you are converting it is already an array.
import Foundation
import UIKit
var myPicture = [String]()
var myPath = [String]()
var mylabel = [String]()
let jsonString = "[{\"picture\" : \"Picture 1 \", \"path\": \"Path 1\" , \"label\" : \"Label 1\"}]"
//Convert jsonString to NSData
let myData = jsonString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!
do{
let promoJson = try NSJSONSerialization.JSONObjectWithData(myData, options:.AllowFragments) as! NSArray
for promtions in promoJson {
if let picture = promtions["picture"] as? String
{
myPicture.append(picture)
if let path = promtions["path"] as? String
{
myPath.append(path)
if let label = promtions["label"] as? String
{
mylabel.append(label)
}
}
}
}
}catch
{
print("Error with Json: \(error)")
}
print(myPicture.first) // "Optional("Picture 1 ")\n"
print(myPath.first) // "Optional("Path 1")\n"
print(mylabel.first) // "Optional("Label 1")\n"
This does the job.

Resources