private async Task TabAnimation(TabItemPage page)
{
var prevunderline = this.Children.FirstOrDefault(x => x.AutomationId == "underlineitem");
//Adding underline on item
BoxView underline = new BoxView()
{
AutomationId = "underlineitem",
HeightRequest = 1,
StyleId = page.Index.ToString(),
Color = TitleActiveTextColor,
WidthRequest = 70,
Opacity = 0,
HorizontalOptions = LayoutOptions.Center,
VerticalOptions = LayoutOptions.EndAndExpand
};
//remove previous underline and animate it
async Task <bool> AnimatePrev()
{
if (prevunderline != null)
{
int spaces = (int.Parse(underline.StyleId) - int.Parse(prevunderline.StyleId)) * 100;
await prevunderline.TranslateTo(spaces, 0, 200, Easing.SinOut);
return(this.Children.Remove(prevunderline));
}
else
{
return(await Task.FromResult(true));
}
};
//add a new underline and animate it
async Task <bool> AnimateAddUnderline()
{
this.Children.Add(underline, page.Index, 1);
return(await underline.FadeTo(100, 1000, Easing.SinIn));
};
//runs the two actions at the same time
await Task.WhenAny <bool>
(
AnimatePrev(),
AnimateAddUnderline()
);
//highligth tab button title
var tabs = this.Children.Where(tb => tb.StyleId != null && tb.StyleId.Contains("tabbutton")).ToList();
//foreach (StackLayout tb in tabs)
foreach (CustomFrame tb in tabs)
{
var buttonarea = tb.Content as StackLayout;
var title = buttonarea.Children.FirstOrDefault(lbl => lbl is Label) as Label;
if (tb.StyleId == $"tabbutton{page.Index}")
{
title.TextColor = TitleActiveTextColor;
if (page.IconActiveName.Contains("svg"))
{
var icon = buttonarea.Children.FirstOrDefault(ico => ico is SvgCachedImage) as SvgCachedImage;
var xfSource = _imageSourceConverter.ConvertFromInvariantString(page.IconActiveName) as ImageSource;
icon.Source = new SvgImageSource(xfSource, 0, 0, true);
}
else
{
var icon = buttonarea.Children.FirstOrDefault(ico => ico is CachedImage) as CachedImage;
icon.Source = ImageSource.FromFile(page.IconActiveName);
}
tb.StartColor = StartActiveBackgroundColor;
tb.EndColor = EndActiveBackgroundColor;
}
else
{
title.TextColor = TitleTextColor;
var iconnormal = Pages.FirstOrDefault(ico => ico.Index == int.Parse(tb.StyleId.Replace("tabbutton", string.Empty)));
if (iconnormal.IconName.Contains("svg"))
{
var icon = buttonarea.Children.FirstOrDefault(ico => ico is SvgCachedImage) as SvgCachedImage;
var xfSource = _imageSourceConverter.ConvertFromInvariantString(iconnormal.IconName) as ImageSource;
icon.Source = new SvgImageSource(xfSource, 0, 0, true);
}
else
{
var icon = buttonarea.Children.FirstOrDefault(ico => ico is CachedImage) as CachedImage;
icon.Source = ImageSource.FromFile(iconnormal.IconName);
}
tb.StartColor = StartBackgroundColor;
tb.EndColor = EndBackgroundColor;
}
}
}
private async Task OnTappedTabButton(TabItemPage page)
{
await ShowPage(page.Index);
await TabAnimation(page);
}
