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using Unity.UIWidgets.foundation;
using Unity.UIWidgets.painting;
using Unity.UIWidgets.rendering;
using Unity.UIWidgets.ui;
using Unity.UIWidgets.widgets;
namespace Unity.UIWidgets.material
{
public static class CircleAvatarUtils
{
// The default radius if nothing is specified.
public static float _defaultRadius = 20.0f;
// The default min if only the max is specified.
public static float _defaultMinRadius = 0.0f;
// The default max if only the min is specified.
public static float _defaultMaxRadius = float.PositiveInfinity;
}
public class CircleAvatar : StatelessWidget
{
/// The color with which to fill the circle. Changing the background
/// color will cause the avatar to animate to the new color.
///
/// If a [backgroundColor] is not specified, the theme's
/// [ThemeData.primaryColorLight] is used with dark foreground colors, and
/// [ThemeData.primaryColorDark] with light foreground colors.
public readonly Color backgroundColor;
/// The background image of the circle. Changing the background
/// image will cause the avatar to animate to the new image.
///
/// Typically used as a fallback image for [foregroundImage].
///
/// If the [CircleAvatar] is to have the user's initials, use [child] instead.
public readonly ImageProvider backgroundImage;
/// The widget below this widget in the tree.
///
/// Typically a [Text] widget. If the [CircleAvatar] is to have an image, use
/// [backgroundImage] instead.
public readonly Widget child;
/// The default text color for text in the circle.
///
/// Defaults to the primary text theme color if no [backgroundColor] is
/// specified.
///
/// Defaults to [ThemeData.primaryColorLight] for dark background colors, and
/// [ThemeData.primaryColorDark] for light background colors.
public readonly Color foregroundColor;
/// The foreground image of the circle.
///
/// Typically used as profile image. For fallback use [backgroundImage].
public readonly ImageProvider foregroundImage;
/// The maximum size of the avatar, expressed as the radius (half the
/// diameter).
///
/// If [maxRadius] is specified, then [radius] must not also be specified.
///
/// Defaults to [double.infinity].
///
/// Constraint changes are animated, but size changes due to the environment
/// itself changing are not. For example, changing the [maxRadius] from 10 to
/// 20 when the [CircleAvatar] is in an unconstrained environment will cause
/// the avatar to animate from a 20 pixel diameter to a 40 pixel diameter.
/// However, if the [maxRadius] is 40 and the [CircleAvatar] has a parent
/// [SizedBox] whose size changes instantaneously from 20 pixels to 40 pixels,
/// the size will snap to 40 pixels instantly.
public readonly float? maxRadius;
/// The minimum size of the avatar, expressed as the radius (half the
/// diameter).
///
/// If [minRadius] is specified, then [radius] must not also be specified.
///
/// Defaults to zero.
///
/// Constraint changes are animated, but size changes due to the environment
/// itself changing are not. For example, changing the [minRadius] from 10 to
/// 20 when the [CircleAvatar] is in an unconstrained environment will cause
/// the avatar to animate from a 20 pixel diameter to a 40 pixel diameter.
/// However, if the [minRadius] is 40 and the [CircleAvatar] has a parent
/// [SizedBox] whose size changes instantaneously from 20 pixels to 40 pixels,
/// the size will snap to 40 pixels instantly.
public readonly float? minRadius;
/// An optional error callback for errors emitted when loading
/// [backgroundImage].
public readonly ImageErrorListener onBackgroundImageError;
/// An optional error callback for errors emitted when loading
/// [foregroundImage].
public readonly ImageErrorListener onForegroundImageError;
/// The size of the avatar, expressed as the radius (half the diameter).
///
/// If [radius] is specified, then neither [minRadius] nor [maxRadius] may be
/// specified. Specifying [radius] is equivalent to specifying a [minRadius]
/// and [maxRadius], both with the value of [radius].
///
/// If neither [minRadius] nor [maxRadius] are specified, defaults to 20
/// logical pixels. This is the appropriate size for use with
/// [ListTile.leading].
///
/// Changes to the [radius] are animated (including changing from an explicit
/// [radius] to a [minRadius]/[maxRadius] pair or vice versa).
public readonly float? radius;
/// Creates a circle that represents a user.
public CircleAvatar(
Key key = null,
Widget child = null,
Color backgroundColor = null,
Color foregroundColor = null,
ImageProvider backgroundImage = null,
ImageProvider foregroundImage = null,
ImageErrorListener onBackgroundImageError = null,
ImageErrorListener onForegroundImageError = null,
float radius = 0.0f,
float minRadius = 0.0f,
float maxRadius = 0.0f
) : base(key)
{
D.assert(radius == null || minRadius == null && maxRadius == null);
D.assert(backgroundImage != null || onBackgroundImageError == null);
D.assert(foregroundImage != null || onForegroundImageError == null);
this.child = child;
this.backgroundColor = backgroundColor;
this.backgroundImage = backgroundImage;
this.foregroundImage = foregroundImage;
this.onBackgroundImageError = onBackgroundImageError;
this.onForegroundImageError = onForegroundImageError;
this.foregroundColor = foregroundColor;
this.radius = radius;
this.minRadius = minRadius;
this.maxRadius = maxRadius;
}
private float _minDiameter
{
get
{
if (radius == null && minRadius == null && maxRadius == null)
return CircleAvatarUtils._defaultRadius * 2.0f;
return 2.0f * (radius ?? minRadius ?? CircleAvatarUtils._defaultMinRadius);
}
}
private float _maxDiameter
{
get
{
if (radius == null && minRadius == null && maxRadius == null)
return CircleAvatarUtils._defaultRadius * 2.0f;
return 2.0f * (radius ?? maxRadius ?? CircleAvatarUtils._defaultMaxRadius);
}
}
public override Widget build(BuildContext context)
{
D.assert(WidgetsD.debugCheckHasMediaQuery(context));
var theme = Theme.of(context);
var textStyle = theme.primaryTextTheme.subtitle1.copyWith(color: foregroundColor);
var effectiveBackgroundColor = backgroundColor;
if (effectiveBackgroundColor == null)
switch (ThemeData.estimateBrightnessForColor(textStyle.color))
{
case Brightness.dark:
effectiveBackgroundColor = theme.primaryColorLight;
break;
case Brightness.light:
effectiveBackgroundColor = theme.primaryColorDark;
break;
}
else if (foregroundColor == null)
switch (ThemeData.estimateBrightnessForColor(backgroundColor))
{
case Brightness.dark:
textStyle = textStyle.copyWith(color: theme.primaryColorLight);
break;
case Brightness.light:
textStyle = textStyle.copyWith(color: theme.primaryColorDark);
break;
}
var minDiameter = _minDiameter;
var maxDiameter = _maxDiameter;
return new AnimatedContainer(
constraints: new BoxConstraints(
minHeight: minDiameter,
minWidth: minDiameter,
maxWidth: maxDiameter,
maxHeight: maxDiameter
),
duration: material_.kThemeChangeDuration,
decoration: new BoxDecoration(
effectiveBackgroundColor,
backgroundImage != null
? new DecorationImage(
backgroundImage,
onBackgroundImageError,
fit: BoxFit.cover
)
: null,
shape: BoxShape.circle
),
foregroundDecoration: foregroundImage != null
? new BoxDecoration(
image: new DecorationImage(
foregroundImage,
onForegroundImageError,
fit: BoxFit.cover
),
shape: BoxShape.circle
)
: null,
child: child == null
? null
: new Center(
child: new MediaQuery(
// Need to ignore the ambient textScaleFactor here so that the
// text doesn't escape the avatar when the textScaleFactor is large.
data: MediaQuery.of(context).copyWith(textScaleFactor: 1.0f),
child: new IconTheme(
data: theme.iconTheme.copyWith(textStyle.color),
child: new DefaultTextStyle(
style: textStyle,
child: child
)
)
)
)
);
}
}
}