Adding simple error alert for when network connection is down

Would be nice to add a refresh button/pull to refresh and a search bar
for searching other artists.

Author: antnasce

MusicPlayer.xcodeproj/project.pbxproj

@@ -19,6 +19,7 @@
 		0270482F19C8F43500FDA1C5 /* DetailsViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0270482E19C8F43500FDA1C5 /* DetailsViewController.swift */; };
 		0270483119C8F6D000FDA1C5 /* Track.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0270483019C8F6D000FDA1C5 /* Track.swift */; };
 		0270483519C8F80000FDA1C5 /* TrackCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0270483419C8F80000FDA1C5 /* TrackCell.swift */; };
+		ED63ECE81C21694A001ACFC3 /* ErrorAlerter.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED63ECE71C21694A001ACFC3 /* ErrorAlerter.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -48,6 +49,7 @@
 		0270482E19C8F43500FDA1C5 /* DetailsViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DetailsViewController.swift; sourceTree = "<group>"; };
 		0270483019C8F6D000FDA1C5 /* Track.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Track.swift; sourceTree = "<group>"; };
 		0270483419C8F80000FDA1C5 /* TrackCell.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TrackCell.swift; sourceTree = "<group>"; };
+		ED63ECE71C21694A001ACFC3 /* ErrorAlerter.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ErrorAlerter.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -92,6 +94,7 @@
 				0270482A19C8EC3000FDA1C5 /* Blank52.png */,
 				0270480819C8E08B00FDA1C5 /* AppDelegate.swift */,
 				0270480A19C8E08B00FDA1C5 /* SearchResultsViewController.swift */,
+				ED63ECE71C21694A001ACFC3 /* ErrorAlerter.swift */,
 				0270480C19C8E08B00FDA1C5 /* Main.storyboard */,
 				0270480F19C8E08B00FDA1C5 /* Images.xcassets */,
 				0270481119C8E08B00FDA1C5 /* LaunchScreen.xib */,
@@ -237,6 +240,7 @@
 				0270480919C8E08B00FDA1C5 /* AppDelegate.swift in Sources */,
 				0270482919C8E2E700FDA1C5 /* APIController.swift in Sources */,
 				0270482D19C8F35700FDA1C5 /* Album.swift in Sources */,
+				ED63ECE81C21694A001ACFC3 /* ErrorAlerter.swift in Sources */,
 				0270482F19C8F43500FDA1C5 /* DetailsViewController.swift in Sources */,
 				0270483119C8F6D000FDA1C5 /* Track.swift in Sources */,
 			);

MusicPlayer/APIController.swift

@@ -28,11 +28,15 @@ class APIController {
             if(error != nil) {
                 // If there is an error in the web request, print it to the console
                 print(error!.localizedDescription)
+              
+                showErrorAlert(error!.localizedDescription)
+
+                // Bail here because we can't process the data any further
+                return
             }
 
             do {
               let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as! NSDictionary
-              //let results: NSArray = jsonResult["results"] as! NSArray
               self.delegate.didReceiveAPIResults(jsonResult) // THIS IS THE NEW LINE!!
             } catch {
                 // If there is an error parsing JSON, print it to the console

MusicPlayer/ErrorAlerter.swift

@@ -0,0 +1,20 @@
+//
+//  ErrorHandler.swift
+//  MusicPlayer
+//
+//  Created by Ant on 16/12/2015.
+//
+
+import Foundation
+import UIKit
+
+func showErrorAlert(message: String) {
+  
+  dispatch_async(dispatch_get_main_queue()) {
+    let alert = UIAlertView()
+    alert.title = "Hmm, something's not right..."
+    alert.message = message
+    alert.addButtonWithTitle("Got it!")
+    alert.show()
+  }
+}

MusicPlayer/SearchResultsViewController.swift

@@ -50,8 +50,7 @@ class SearchResultsViewController: UIViewController, UITableViewDataSource, UITa
         let urlString = album.thumbnailImageURL
 
         // Check our image cache for the existing key. This is just a dictionary of UIImages
-        //var image: UIImage? = self.imageCache.valueForKey(urlString) as? UIImage
-        var image = self.imageCache[urlString] as UIImage!
+        var image = self.imageCache[urlString]
 
         if( image == nil ) {
             // If the image does not exist, we need to download it