No visible #interface for 'NSManagedObjectContext' declares - ios

Question

[self.managedObjectContext deletedObjects:lastPoint];
This line shows me an error
No visible #interface for 'NSManagedObjectContext' declares the selector 'deletedObjects'.
Here is my code
can any one solve this?
Appdelegate.h
#import <UIKit/UIKit.h>
#import <CoreData/CoreData.h>
#interface AppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
#property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;
#property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator;
- (void)saveContext;
- (NSURL *)applicationDocumentsDirectory;
#end
Appdelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
/* crete the fetch request first*/
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc]initWithEntityName:#"Rectangle"];
NSError *requestError = nil;
/*And execute the fetch request on the context*/
NSArray *rectangle = [self.managedObjectContext executeFetchRequest:fetchRequest error:&requestError];
/*make sure we get the array*/
if ([rectangle count] > 0) {
/*delete the last person in the array*/
Rectangle *lastPoint = [rectangle lastObject];
[self.managedObjectContext deletedObjects:lastPoint];
if ([lastPoint isDeleted]) {
NSLog(#"Successfully deleted the last point...");
NSError *savingError = nil;
if ([self.managedObjectContext save:&savingError]) {
NSLog(#"successfully saved the context");
} else {
NSLog(#"Failed to save the context");
}
} else {
NSLog(#"Failed to delete the last point");
}
} else {
NSLog(#"Could not find any rectangle entities in the context.");
}
return YES;
}

Answer 1

The error message
No visible #interface for 'NSManagedObjectContext' declares the
selector 'deletedObjects'.
tells you that the class NSManagedObjectContext doesn't implement the method deletedObjects. You can check this in the API documentation.
You can use deleteObject: to delete single objects. So change your code to:
[self.managedObjectContext deleteObject:lastPoint];

Answer 2

As the documentation says deletedObjects is the read only property, so it has only getter method without any parameters
So you should access it just by using next
self.managedObjectContext.deletedObjects