How to create a Xamarin Tooltip in code-behind - xamarin

Question

I am testing using the following example. https://github.com/CrossGeeks/TooltipSample
The sample works fine, it even works with Labels (sample uses buttons, images and boxviews). The issue is in my main App I need to create the tooltips in code behind.
To test how to do it, in the very same solution (from that above example) I created a TestPage and made it my MainPage in App.xaml.cs. The XAML looks like this:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="ToolTipSample.TestPage">
<ContentPage.Content>
<StackLayout
x:Name="mainLayout"
BackgroundColor="Yellow">
<StackLayout.GestureRecognizers>
<TapGestureRecognizer Tapped="Handle_Tapped"/>
</StackLayout.GestureRecognizers>
</StackLayout>
</ContentPage.Content>
The code-behind looks like this:
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using ToolTipSample.Effects;
namespace ToolTipSample
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class TestPage : ContentPage
{
public TestPage()
{
InitializeComponent();
var actionLabel = new Label
{
Text = "Show Tooltip",
WidthRequest = 150,
VerticalOptions = LayoutOptions.StartAndExpand,
HorizontalOptions = LayoutOptions.Center,
BackgroundColor = Color.Wheat
};
// Add tooltip to action label
TooltipEffect.SetPosition(actionLabel, TooltipPosition.Bottom);
TooltipEffect.SetBackgroundColor(actionLabel, Color.Silver);
TooltipEffect.SetTextColor(actionLabel, Color.Teal);
TooltipEffect.SetText(actionLabel, "This is the tooltip");
TooltipEffect.SetHasTooltip(actionLabel, true);
actionLabel.Effects.Add(Effect.Resolve($"CrossGeeks.{nameof(TooltipEffect)}"));
mainLayout.Children.Add(actionLabel);
}
void Handle_Tapped(object sender, System.EventArgs e)
{
foreach (var c in mainLayout.Children)
{
if (TooltipEffect.GetHasTooltip(c))
{
TooltipEffect.SetHasTooltip(c, false);
TooltipEffect.SetHasTooltip(c, true);
}
}
}
}
}
All other code unchanged.
When I tap the label, the tooltip appears as expected. But when I tap the background it does not disappear (like those created in XAML in the sample).
One other thing. If I tap twice it disappears.
Can anyone see what I am missing?
Thanks.

Answer 1

According to your description and code, you can delete the following line code to achieve your requirement.
actionLabel.Effects.Add(Effect.Resolve($"CrossGeeks.{nameof(TooltipEffect)}"));
You don't need to add effect for control when page load, because this effect will be added when you click this control by these code:
static void OnHasTooltipChanged(BindableObject bindable, object oldValue, object newValue)
{
var view = bindable as View;
if (view == null)
{
return;
}
bool hasTooltip = (bool)newValue;
if (hasTooltip)
{
view.Effects.Add(new ControlTooltipEffect());
}
else
{
var toRemove = view.Effects.FirstOrDefault(e => e is ControlTooltipEffect);
if (toRemove != null)
{
view.Effects.Remove(toRemove);
}
}
}