Hiding determinate progress dialogs doesn't stop animation threads

[nathancassano]

When a determinate progress dialog is closed before it ends and another determinate dialog is opened then the two threads fight to control the progress meter.

Proposed Patch:

diff --git a/src/ios/ProgressIndicator.h b/src/ios/ProgressIndicator.h
index 8f7c28a..2270937 100644
--- a/src/ios/ProgressIndicator.h
+++ b/src/ios/ProgressIndicator.h
@@ -4,7 +4,7 @@
 @interface ProgressIndicator: CDVPlugin {
 }
 
-@property (nonatomic, assign) MBProgressHUD* progressIndicator;
+@property (nonatomic, weak) MBProgressHUD* progressIndicator;
 
-@end
\ No newline at end of file
+@end
diff --git a/src/ios/ProgressIndicator.m b/src/ios/ProgressIndicator.m
index 550b53a..17475ad 100644
--- a/src/ios/ProgressIndicator.m
+++ b/src/ios/ProgressIndicator.m
@@ -399,19 +399,24 @@ - (void)showMultiple:(CDVInvokedUrlCommand*)command {
 
 - (void)hide:(CDVInvokedUrlCommand*)command
 {
-       if (!self.progressIndicator) {
-               CDVPluginResult* pluginResult = [CDVPluginResult resultWithStatus:CDVCommandStatus_ERROR];
-               [self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
-               return;
-       }
-       [self.progressIndicator hide:YES];
+    if (!self.progressIndicator) {
+        CDVPluginResult* pluginResult = [CDVPluginResult resultWithStatus:CDVCommandStatus_ERROR];
+        [self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
+        return;
+    }
+
+    if ( self.progressIndicator.taskInProgress == YES )
+        self.progressIndicator.taskInProgress = NO;
+    else
+        [self.progressIndicator hide:YES];
+
     self.progressIndicator = nil;
+
     CDVPluginResult* pluginResult = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsString:@""];
     [self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
 }

 
-
 /**
  * PROGRESS TASK EVENT
  */
@@ -420,11 +425,15 @@ - (void)progressTask:(NSNumber *)increment{
     
     // get increment value
     int _increment = [increment intValue];
+
+    MBProgressHUD* progressIndicator = self.progressIndicator;
     
     float progress = 0.0f;
     while (progress < 1.0f) {
+        if ( progressIndicator.taskInProgress == NO ) break;
+
         progress += 0.01f;
-        self.progressIndicator.progress = progress;
+        progressIndicator.progress = progress;
         
         // increment in microseconds (100000mms = 1s)
         usleep(_increment);