Xib shows empty screen although it works fine in the designer - ios

Question

I really don't understand what I am doing wrong here. I've designed a very very simple .xib file that show a textview and a button. In the designer it works just fine. Scaling works just as would expect it. But when I run the program in the simulator I only get an empty screen. A few times I have seen the lower part of the button just beneath the navigation bar which leads me to the conclusion that the views must be somewhere at the top outside the viewable area.
As you can see in the images below I've added several constraints to the views that scale the views in the designer just fine. I've tried adding top spacing. Contain the views in a StackView but nothing seems to do the trick. What am I missing?
Here's the code that start the view using MvvmCross.
/// <summary>
/// Call the MvvmCross ShowViewModel method
/// </summary>
public bool Show<TViewModel>(IMvxBundle presentationBundle = null)
where TViewModel : IMvxViewModel
{
return base.ShowViewModel<TViewModel>(presentationBundle: presentationBundle);
}
/// <summary>
/// Show a view with viewmodel
/// </summary>
public bool Show<TViewModel>()
where TViewModel : IMvxViewModel
{
return Show<TViewModel>();
}
The presentation is handled in a custom viewpresenter:
using MvvmCross.Core.ViewModels;
using MvvmCross.iOS.Views;
using MvvmCross.iOS.Views.Presenters;
using MvvmCross.Platform;
using Notifier.Classes;
using Notifier.Interfaces;
using UIKit;
using static Notifier.Classes.ViewModelController;
namespace Notifier.iOS.Classes.MvvmCross
{
public class ViewPresenter : MvxIosViewPresenter
{
private IMvxIosViewCreator _viewCreator;
private IPlatformLog _log;
private IPlatformLog Log => _log == null ? _log = Mvx.Resolve<IPlatformLog>() : _log;
protected IMvxIosViewCreator ViewCreator
{
get { return _viewCreator ?? (_viewCreator = Mvx.Resolve<IMvxIosViewCreator>()); }
}
public ViewPresenter(IUIApplicationDelegate applicationDelegate, UIWindow window)
: base(applicationDelegate, window)
{
}
public override void Show(MvxViewModelRequest request)
{
base.Show(request);
}
}
}
Here's the content of the .xib:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="12120" systemVersion="16F73" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES">
<dependencies>
<plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12088"/>
<capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>
<objects>
<placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner" customClass="HomeView">
<connections>
<outlet property="view" destination="2" id="RRd-Eg-VrN"/>
<outlet property="Registration" destination="11" id="name-outlet-11"/>
</connections>
</placeholder>
<placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
<view contentMode="scaleToFill" id="2" horizontalHuggingPriority="1">
<rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
<autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
<color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
<subviews>
<textView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" textAlignment="natural" id="10" translatesAutoresizingMaskIntoConstraints="NO">
<rect key="frame" x="16" y="16" width="568" height="128"/>
<color key="backgroundColor" white="1" alpha="1" colorSpace="calibratedWhite"/>
<string key="text">Lorem ipsum dolor sit er elit lamet, consectetaur cillium adipisicing pecu, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Nam liber te conscient to factor tum poen legum odioque civiuda.</string>
<fontDescription key="fontDescription" type="system" pointSize="14"/>
<textInputTraits key="textInputTraits" autocapitalizationType="sentences"/>
</textView>
<button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" id="11" translatesAutoresizingMaskIntoConstraints="NO">
<rect key="frame" x="16" y="188" width="568" height="30"/>
<state key="normal" title="Button">
<color key="titleShadowColor" white="0.5" alpha="1" colorSpace="calibratedWhite"/>
</state>
</button>
</subviews>
<constraints>
<constraint id="14" firstItem="2" firstAttribute="trailing" secondItem="10" secondAttribute="trailing" constant="16"/>
<constraint id="15" firstItem="10" firstAttribute="leading" secondItem="2" secondAttribute="leading" constant="16"/>
<constraint id="16" firstItem="11" firstAttribute="leading" secondItem="2" secondAttribute="leading" constant="16"/>
<constraint id="17" firstItem="2" firstAttribute="trailing" secondItem="11" secondAttribute="trailing" constant="16"/>
</constraints>
</view>
</objects>
<simulatedMetricsContainer key="defaultSimulatedMetrics">
<simulatedScreenMetrics key="destination" type="retina47"/>
</simulatedMetricsContainer>
</document>
This is the generic view in the designer:
This is the designer for a specifice iPhone:
And this is what I see in the simulator:

Answer 1

It should be due to constraints problem. Please check whether your constraint is define correctly. When the constraint is define correctly, you should see blue lines only when select your view in xib.
From your screenshots, you are only defining leading and trailing constraints. Please also define the top and height constraint.