Updated to iOS8 alert windows to avoid deprecation warnings

modules/juce_gui_basics/native/juce_ios_Windowing.mm

@@ -124,20 +124,27 @@ void LookAndFeel::playAlertSound()
 //==============================================================================
 class iOSMessageBox;
 
-} // (juce namespace)
+#if defined (__IPHONE_8_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_8_0
+ #define JUCE_USE_NEW_IOS_ALERTWINDOW 1
+#endif
 
-@interface JuceAlertBoxDelegate  : NSObject <UIAlertViewDelegate>
-{
-@public
-    iOSMessageBox* owner;
-}
+#if ! JUCE_USE_NEW_IOS_ALERTWINDOW
+    } // (juce namespace)
 
-- (void) alertView: (UIAlertView*) alertView clickedButtonAtIndex: (NSInteger) buttonIndex;
+    @interface JuceAlertBoxDelegate  : NSObject <UIAlertViewDelegate>
+    {
+    @public
+        iOSMessageBox* owner;
+    }
 
-@end
+    - (void) alertView: (UIAlertView*) alertView clickedButtonAtIndex: (NSInteger) buttonIndex;
+
+    @end
+
+    namespace juce
+    {
+#endif
 
-namespace juce
-{
 
 class iOSMessageBox
 {
@@ -145,9 +152,30 @@ public:
     iOSMessageBox (const String& title, const String& message,
                    NSString* button1, NSString* button2, NSString* button3,
                    ModalComponentManager::Callback* cb, const bool async)
-        : result (0), resultReceived (false), delegate (nil), alert (nil),
-          callback (cb), isYesNo (button3 != nil), isAsync (async)
+        : result (0), resultReceived (false), callback (cb), isAsync (async)
     {
+       #if JUCE_USE_NEW_IOS_ALERTWINDOW
+        if (currentlyFocusedPeer != nullptr)
+        {
+            UIAlertController* alert = [UIAlertController alertControllerWithTitle: juceStringToNS (title)
+                                                                           message: juceStringToNS (message)
+                                                                    preferredStyle: UIAlertControllerStyleAlert];
+            addButton (alert, button1, 0);
+            addButton (alert, button2, 1);
+            addButton (alert, button3, 2);
+
+            [currentlyFocusedPeer->controller presentViewController: alert
+                                                           animated: YES
+                                                         completion: nil];
+        }
+        else
+        {
+            // Since iOS8, alert windows need to be associated with a window, so you need to
+            // have at least one window on screen when you use this
+            jassertfalse;
+        }
+
+       #else
         delegate = [[JuceAlertBoxDelegate alloc] init];
         delegate->owner = this;
 
@@ -158,12 +186,15 @@ public:
                                  otherButtonTitles: button2, button3, nil];
         [alert retain];
         [alert show];
+       #endif
     }
 
     ~iOSMessageBox()
     {
+       #if ! JUCE_USE_NEW_IOS_ALERTWINDOW
         [alert release];
         [delegate release];
+       #endif
     }
 
     int getResult()
@@ -172,7 +203,11 @@ public:
 
         JUCE_AUTORELEASEPOOL
         {
+           #if JUCE_USE_NEW_IOS_ALERTWINDOW
+            while (! resultReceived)
+           #else
             while (! (alert.hidden || resultReceived))
+           #endif
                 [[NSRunLoop mainRunLoop] runUntilDate: [NSDate dateWithTimeIntervalSinceNow: 0.01]];
         }
 
@@ -194,28 +229,43 @@ public:
 private:
     int result;
     bool resultReceived;
-    JuceAlertBoxDelegate* delegate;
-    UIAlertView* alert;
     ScopedPointer<ModalComponentManager::Callback> callback;
-    const bool isYesNo, isAsync;
+    const bool isAsync;
+
+   #if JUCE_USE_NEW_IOS_ALERTWINDOW
+    void addButton (UIAlertController* alert, NSString* text, int index)
+    {
+        if (text != nil)
+            [alert addAction: [UIAlertAction actionWithTitle: text
+                                                       style: UIAlertActionStyleDefault
+                                                     handler: ^(UIAlertAction* action) { this->buttonClicked (index); }]];
+    }
+   #else
+    UIAlertView* alert;
+    JuceAlertBoxDelegate* delegate;
+   #endif
 
     JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (iOSMessageBox)
 };
 
-} // (juce namespace)
 
-@implementation JuceAlertBoxDelegate
+#if ! JUCE_USE_NEW_IOS_ALERTWINDOW
+    } // (juce namespace)
 
-- (void) alertView: (UIAlertView*) alertView clickedButtonAtIndex: (NSInteger) buttonIndex
-{
-    owner->buttonClicked ((int) buttonIndex);
-    alertView.hidden = true;
-}
+    @implementation JuceAlertBoxDelegate
 
-@end
+    - (void) alertView: (UIAlertView*) alertView clickedButtonAtIndex: (NSInteger) buttonIndex
+    {
+        owner->buttonClicked ((int) buttonIndex);
+        alertView.hidden = true;
+    }
+
+    @end
+
+    namespace juce
+    {
+#endif
 
-namespace juce
-{
 
 //==============================================================================
 #if JUCE_MODAL_LOOPS_PERMITTED