Max height of dialog - perhaps more a question?

[john-dalsgaard]

Description

I have a dialog defined by this XAML:

<extra:DialogView
    xmlns="http://xamarin.com/schemas/2014/forms"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
    xmlns:extra="clr-namespace:AiForms.Dialogs.Abstractions;assembly=AiForms.Dialogs.Abstractions"
    xmlns:resource="clr-namespace:Angler.Resources"
    UseCurrentPageLocation="False"
    OverlayColor="#80000000"
    ProportionalWidth="0.9"
    HorizontalLayoutAlignment="Center"
    VerticalLayoutAlignment="Center"
    x:Name="Dialog" 
    x:Class="Angler.Views.CustomControls.NotifyDialog">
    <ContentView BindingContext="{x:Reference Dialog}">
        <StackLayout BackgroundColor="White" Padding="10">
            <Label Text="{Binding Title}"
                   Padding="0,10"
                   Style="{StaticResource ConfirmDialogHeading}"></Label>
            <ScrollView BackgroundColor="Transparent">
                <Label Text="{Binding Message}"
                       Style="{StaticResource ConfirmDialogText}"></Label>
            </ScrollView>
            <Button Text="{Binding OkButton}"
                    Clicked="OkButtonClicked"
                    Padding="1"/>
        </StackLayout>
    </ContentView>
</extra:DialogView>

The contents of the scroll view is edited by an administrator (in several languages) so it can take up a lot of space on devices with a small screen.

So if I set the ProportionalHeight the dialog will not auto size to fit the contents (and potentially look way too large/high). However, if there is a lot of content without ProportionalHeight the dialog will get bigger than the screen - and the user cannot read the entire message or press the button to close the dialog....

Steps to Reproduce

1. Just create a dialog with the above XAML and call it with a long text (e.g. with several new lines)

Expected Behavior

That the dialog would not flow outside the actual screen

Actual Behavior

Dialog grows bigger than visual screen - and user can't close it

Platforms

• [x ] Android
• [ x] iOS

Basic Information

• AiForms.SettingsView 1.0.3 (and earlier)
• Xamarin.Forms 4.6.0.847
• Affected Devices: All phones

Any suggestions I may have overlooked would be much appreciated :-)

[john-dalsgaard]

I had a look at the methods I could override - and tried a simple test in the code-behind of the dialog:

protected override SizeRequest OnMeasure(double widthConstraint, double heightConstraint)
{
    var h = Dialog.Height;
    if (heightConstraint > 500)
    {
        heightConstraint = 500;
    }
    return base.OnMeasure(widthConstraint, heightConstraint);
}

... but that doesn't make any difference ;-)

Perhaps a different implementation of the above "thought" could do the trick - but apparently with some other code.

[john-dalsgaard]

I can see that I could set the ProportionalHeight in the Setup method - but at this time I can't find out the calculated height of the contents.... :-(

[jmkyarrow]

If it were me I'd set proportional height to 1 with transparent overlay colour, have my contents vertically centered within a parent absolute layout, adding a tap gesture recogniser to the absolute layout and call DialogNotifier.Cancel when the tapped event fires, but I suppose you're looking for a more built-in way.

Are you supposed to put 'h' in the if statement instead? Not sure why you've defined it if it wasn't for that...

[john-dalsgaard]

Ahh... the 'h' was just a test to be able to see what was going on in the debugger.

I appreciate the way you suggest to do it. However, I feel it should be possible to do way simpler - if just I could get my hands on the height of the dialog and screen - and if the dialog is higher then 90% of the screen then set the proportional height to 0.9... - but I couldn't figure out where to make that happen. Once I had the heights then changing the proportional height didn't have any effect.... :-(