Essentials: [Bug] Launcher.OpenAsync with file on iPad not working

[RhomGit]

Description

I am testing v1.2.0-Pre the new Launcher.OpenAsync included with this: https://github.com/xamarin/Essentials/pull/773

The Share and the Open work wonderful with Android. On iOS I seem to be struggling with the Open. Share works fine on iOS.

Steps to Reproduce

1. Download a file (I have tried .png and .pdf). e.g. "/var/mobile/Containers/Data/Application/34F7C5-D1-E4-906C-B02/Library/Caches/10044_13583.pdf"
2. Call: await Launcher.OpenAsync(new OpenFileRequest(this.fileCaption, new ReadOnlyFile(fn)));

Expected Behavior

The native app selection dialog opens up like it does on Android. Selecting this opens the file in the selected app.

Actual Behavior

Nothing at all happens.

Basic Information

This only affects iOS. I have tried on a physical 12.3 iPad and a 12.2 emulator.
Xamarin.Essentials v1.2.0-Pre

Please note: when I call this:
var uri = new Uri(fn);
var supportsUri = await Launcher.CanOpenAsync(uri.Scheme + @"://");
the uri.Scheme = "file" and the Launcher.CanOpenAsync returns false.

Reproduction Link

string fn = this.FileName_FullIncludingPath;
var uri = new Uri(fn);
var supportsUri = await Launcher.CanOpenAsync(uri.Scheme + @"://");
if (supportsUri)
await Launcher.OpenAsync(new OpenFileRequest(this.fileCaption, new ReadOnlyFile(fn)));

[jamesmontemagno]

CanOpenAsync is only for non-files... so no need to check that. Try it without that.

[RhomGit]

Yep, sorry if it was ambiguous. I was using just:
await Launcher.OpenAsync(new OpenFileRequest(this.fileCaption, new ReadOnlyFile(fn)));
but I had also tried the "CanOpenAsync" and added that info in as I thought it might be the cause.

Launcher.OpenAsync() just does nothing. No exception or diagnostic message that I can see.

[RhomGit]

Hi again, I decided to download the Xamarin.Essentials code and link it up to see what is going on. Unfortunately I don't have anything interesting to report

In the "PlatformOpenAsync" function:

• request.File.ContentType = "image/png" and "application/pdf"
• documentController is created and vc.View and vc.View.Frame seem ok to me also.

After reading: https://developer.apple.com/documentation/uikit/uidocumentinteractioncontroller/1616807-presentopeninmenu

Return value: true if this method was able to display the menu or false if it was not.

but the PresentOpenInMenu() is actually returning true.

Below is the vc.View being used:

{<UIView: 0x105fb4d00; frame = (0 0; 768 1024); autoresize = W+H; layer = <CALayer: 0x282b65660>>}
    base: {UIKit.UIResponder}
    AccessibilityHint: (null)
    AccessibilityIdentifier: (null)
    AccessibilityLabel: (null)
    Alpha: 1
    BackgroundColor: {UIKit.UIColor}
    BottomAnchor: {UIKit.NSLayoutYAxisAnchor}
    Bounds: {CoreGraphics.CGRect}
    CanBecomeFocused: false
    Center: {CoreGraphics.CGPoint}
    ClassHandle: 0x262e1a408
    ContentScaleFactor: 1
    CoordinateSpace: {UIKit.UIView}
    Focused: false
    Frame: {CoreGraphics.CGRect}
    GestureRecognizers: (null)
    HeightAnchor: {UIKit.NSLayoutDimension}
    Hidden: false
    IntrinsicContentSize: {CoreGraphics.CGSize}
    IsAccessibilityElement: false
    Layer: {CoreAnimation.CALayer}
    LeadingAnchor: {UIKit.NSLayoutXAxisAnchor}
    PreferredFocusedView: {UIKit.UIView}
    SafeAreaInsets: {UIKit.UIEdgeInsets}
    Subviews: {UIKit.UIView[1]}
    Superview: {UIKit.UIWindow}
    Tag: 0
    TintColor: {UIKit.UIColor}
    TopAnchor: {UIKit.NSLayoutYAxisAnchor}
    TrailingAnchor: {UIKit.NSLayoutXAxisAnchor}
    Transform: {CoreGraphics.CGAffineTransform}
    UserInteractionEnabled: true
    WidthAnchor: {UIKit.NSLayoutDimension}
    Window: {UIKit.UIWindow}

[jamesmontemagno]

Ah... interesting... so this is just on an iPad and iPad simulator? Perhaps it is showing off the screen....hmmmm

How about on a phone?

[RhomGit]

Good call.

I did a test on an iPhone Xs Max 12.2 simulator:

[jamesmontemagno]

Fixed up and will be in next release.