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我正在制作的应用程序Polyline根据用户坐标绘制CLLocationManager(这些都保存在一起NSMutableArray)

当应用关闭时,当前折线消失.如何在应用程序启动时存储要在CoreData中检索的点数组？用户在启动应用程序后所采取的所有过去"路线"应该被恢复并覆盖在地图上(这可能相当多,因此CoreData似乎是我收集的最佳选择).

这是我用来从加载的坐标创建MKPolyline的代码

-(IBAction)didClickLoadCoordinates:(id)sender {
// get a reference to the appDelegate so you can access the global managedObjectContext
AppDelegate *appDelegate = [UIApplication sharedApplication].delegate;

NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Route"];
NSError *error;
id results = [appDelegate.managedObjectContext executeFetchRequest:request error:&error];

if ([results count]) {
    polyLine = (Route *)(results[0]);
    NSArray *coordinates = polyLine.coordinates;
    int ct = 0;
    for (CLLocation *loc in coordinates) {
        NSLog(@"location %d: %@", ct++, loc);


    }


    // this copies the array to your mutableArray …