UIAlertController调整文字对齐

UIAlertController* alertVC = [UIAlertController alertControllerWithTitle:@"" message:message preferredStyle:UIAlertControllerStyleAlert];
UIView *subView1 = alertVC.view.subviews[0];
UIView *subView2 = subView1.subviews[0];
UIView *subView3 = subView2.subviews[0];
UIView *subView4 = subView3.subviews[0];
UIView *subView5 = subView4.subviews[0];
//取message：
UILabel *message = subView5.subviews[1];
message.textAlignment = NSTextAlignmentLeft;
UIAlertAction* cancelAction = [UIAlertAction actionWithTitle:NSLocalizedString(@"ok",nil) style:UIAlertActionStyleCancel handler:nil];
[alertVC addAction:cancelAction];
[[UIApplication sharedApplication].keyWindow.rootViewController presentViewController:alertVC animated:YES completion:nil];