/// <summary>
/// Implementation of method required by the <see cref="T:XFGloss.IXFGlossRenderer"/> interface that the
/// <see cref="T:XFGloss.IGradientRenderer"/> interface extends. Applies the passed
/// <see cref="T:XFGloss.XFGlossElement"/> properties to the Android cell controls.
/// </summary>
/// <param name="propertyName">The name of the XFGloss attached BindableProperty that changed</param>
/// <param name="element">The <see cref="T:XFGloss.XFGlossElement"/> instance that changed</param>
/// <typeparam name="TElement">The type <see cref="T:XFGloss.XFGlossElement"/> that changed</typeparam>
public void CreateNativeElement <TElement>(string propertyName, TElement element) where TElement : XFGlossElement
{
// No need to check property name yet. BackgroundGradient is the only property currently supported.
//if (propertyName == CellGloss.BackgroundGradientProperty.PropertyName && element is Gradient)
var nativeCell = GetNativeCell();
if (nativeCell != null)
{
RemoveBackgroundGradientDrawable(nativeCell);
// The material design ripple effect was introduced in Lollipop. Use it if we're running on that or newer
if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.Lollipop)
{
var ripple = BackgroundRippleDrawable.Create(new XFGlossPaintDrawable(element as Gradient),
(element as Gradient).AverageColor.ToAndroid());
nativeCell.SetOnTouchListener(ripple);
nativeCell.Background = ripple;
}
else
{
// Otherwise we just darken/lighten the cell background depending on how dark the background is
nativeCell.Background =
BackgroundStateListDrawable.Create(new XFGlossPaintDrawable(element as Gradient),
(element as Gradient).AverageColor.ToAndroid());
}
}
}
/// <summary>
/// Implementation of the cross-platform base class's abstract UpdateProperties method. Used to apply the
/// XFGloss attached BindableProperty values for the property specified by the propertyName parameter.
/// </summary>
/// <param name="cell">The associated <see cref="T:Xamarin.Forms.Cell"/> instance</param>
/// <param name="nativeCell">The native Android view used to display the cell contents</param>
/// <param name="propertyName">The name of the XFGloss attached BindableProperty that changed</param>
protected override void UpdateProperties(Cell cell, AView nativeCell, string propertyName)
{
// BackgroundColor and BackgroundGradient properties
// We shouldn't apply BOTH a background gradient and solid color. The gradient takes preference.
Gradient bkgrndGradient = (Gradient)cell.GetValue(CellGloss.BackgroundGradientProperty);
if (bkgrndGradient != null && bkgrndGradient.UpdateProperties(CellGloss.BackgroundGradientProperty.PropertyName,
this, propertyName))
{
// We don't need to handle BackgroundColor if a BackgroundGradient is assigned/updated
return;
}
// We only process background color if a gradient wasn't applied by the base class.
// BackgroundColor property
if (propertyName == null || propertyName == CellGloss.BackgroundColorProperty.PropertyName)
{
var bk = nativeCell.Background;
Color bkgrndColor = (Color)cell.GetValue(CellGloss.BackgroundColorProperty);
// We don't want to assign a background color if the default color is specified
// and we're updating all properties.
if (propertyName != null || bkgrndColor != Color.Default)
{
AColor aBkColor = (bkgrndColor != Color.Default) ? bkgrndColor.ToAndroid() : AColor.Transparent;
// The material design ripple effect was introduced in Lollipop. Use it if we're running on that or newer
if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.Lollipop)
{
var ripple = BackgroundRippleDrawable.Create(aBkColor);
nativeCell.SetOnTouchListener(ripple);
nativeCell.Background = ripple;
}
else
{
// Pre-lollipop means no ripple available
// See FAQ at bottom of http://android-developers.blogspot.com/2014/10/appcompat-v21-material-design-for-pre.html
// Q: Why are there no ripples on pre-Lollipop?
// A: A lot of what allows RippleDrawable to run smoothly is Android 5.0’s new RenderThread.
// To optimize for performance on previous versions of Android, we've left RippleDrawable out
// for now.
nativeCell.Background = BackgroundStateListDrawable.Create(aBkColor);
}
}
}
}
public static BackgroundStateListDrawable Create(AColor backgroundColor)
{
return(BackgroundStateListDrawable.Create(new ColorDrawable(backgroundColor), backgroundColor));
}
