fix iOS 13 - XCode 11

iOSClient/Login/CCLogin.m

@@ -41,6 +41,7 @@
     [super viewDidLoad];
     
     appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
+    Ivar ivar =  class_getInstanceVariable([UITextField class], "_placeholderLabel");
 
     // Background color
     self.view.backgroundColor = [NCBrandColor sharedInstance].customer;
@@ -57,7 +58,8 @@
     _baseUrl.textColor = [NCBrandColor sharedInstance].customerText;
     _baseUrl.tintColor = [NCBrandColor sharedInstance].customerText;
     _baseUrl.placeholder = NSLocalizedString(@"_login_url_", nil);
-    [_baseUrl setValue:[UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7] forKeyPath:@"_placeholderLabel.textColor"];
+    UILabel *baseUrlPlaceholder = object_getIvar(_baseUrl, ivar);
+    baseUrlPlaceholder.textColor = [UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7];
     [self.baseUrl setFont:[UIFont systemFontOfSize:13]];
     [self.baseUrl setDelegate:self];
     
@@ -66,7 +68,9 @@
     _user.textColor = [NCBrandColor sharedInstance].customerText;
     _user.tintColor = [NCBrandColor sharedInstance].customerText;
     _user.placeholder = NSLocalizedString(@"_username_", nil);
-    [_user setValue:[UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7] forKeyPath:@"_placeholderLabel.textColor"];
+    UILabel *userPlaceholder = object_getIvar(_user, ivar);
+    userPlaceholder.textColor = [UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7];
+
     [self.user setFont:[UIFont systemFontOfSize:13]];
     [self.user setDelegate:self];
 
@@ -75,7 +79,8 @@
     _password.textColor = [NCBrandColor sharedInstance].customerText;
     _password.tintColor = [NCBrandColor sharedInstance].customerText;
     _password.placeholder = NSLocalizedString(@"_password_", nil);
-    [_password setValue:[UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7] forKeyPath:@"_placeholderLabel.textColor"];
+    UILabel *passwordPlaceholder = object_getIvar(_password, ivar);
+    passwordPlaceholder.textColor = [UIColor colorWithRed:255.0/255.0 green:255.0/255.0 blue:255.0/255.0 alpha:0.7];
     [self.password setFont:[UIFont systemFontOfSize:13]];
     [self.password setDelegate:self];