Source code
package android.support.v4.widget;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RadialGradient;
import android.graphics.Shader.TileMode;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.OvalShape;
import android.os.Build.VERSION;
import android.support.v4.view.ViewCompat;
import android.view.animation.Animation.AnimationListener;
import android.widget.ImageView;
class CircleImageView extends ImageView {
private static final int FILL_SHADOW_COLOR = 1023410176;
private static final int KEY_SHADOW_COLOR = 503316480;
private static final int SHADOW_ELEVATION = 4;
private static final float SHADOW_RADIUS = 3.5f;
private static final float X_OFFSET = 0.0f;
private static final float Y_OFFSET = 1.75f;
private AnimationListener mListener;
private int mShadowRadius;
private class OvalShadow extends OvalShape {
private int mCircleDiameter;
private RadialGradient mRadialGradient;
private Paint mShadowPaint = new Paint();
public OvalShadow(int shadowRadius, int circleDiameter) {
CircleImageView.this.mShadowRadius = shadowRadius;
this.mCircleDiameter = circleDiameter;
this.mRadialGradient = new RadialGradient((float) (this.mCircleDiameter / 2), (float) (this.mCircleDiameter / 2), (float) CircleImageView.this.mShadowRadius, new int[]{CircleImageView.FILL_SHADOW_COLOR, 0}, null, TileMode.CLAMP);
this.mShadowPaint.setShader(this.mRadialGradient);
}
public void draw(Canvas canvas, Paint paint) {
int viewWidth = CircleImageView.this.getWidth();
int viewHeight = CircleImageView.this.getHeight();
canvas.drawCircle((float) (viewWidth / 2), (float) (viewHeight / 2), (float) ((this.mCircleDiameter / 2) + CircleImageView.this.mShadowRadius), this.mShadowPaint);
canvas.drawCircle((float) (viewWidth / 2), (float) (viewHeight / 2), (float) (this.mCircleDiameter / 2), paint);
}
}
public CircleImageView(Context context, int color, float radius) {
ShapeDrawable circle;
super(context);
float density = getContext().getResources().getDisplayMetrics().density;
int diameter = (int) ((radius * density) * 2.0f);
int shadowYOffset = (int) (Y_OFFSET * density);
int shadowXOffset = (int) (0.0f * density);
this.mShadowRadius = (int) (SHADOW_RADIUS * density);
if (elevationSupported()) {
circle = new ShapeDrawable(new OvalShape());
ViewCompat.setElevation(this, 4.0f * density);
} else {
circle = new ShapeDrawable(new OvalShadow(this.mShadowRadius, diameter));
ViewCompat.setLayerType(this, 1, circle.getPaint());
circle.getPaint().setShadowLayer((float) this.mShadowRadius, (float) shadowXOffset, (float) shadowYOffset, KEY_SHADOW_COLOR);
int padding = this.mShadowRadius;
setPadding(padding, padding, padding, padding);
}
circle.getPaint().setColor(color);
setBackgroundDrawable(circle);
}
private boolean elevationSupported() {
return VERSION.SDK_INT >= 21;
}
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (!elevationSupported()) {
setMeasuredDimension(getMeasuredWidth() + (this.mShadowRadius * 2), getMeasuredHeight() + (this.mShadowRadius * 2));
}
}
public void setAnimationListener(AnimationListener listener) {
this.mListener = listener;
}
public void onAnimationStart() {
super.onAnimationStart();
if (this.mListener != null) {
this.mListener.onAnimationStart(getAnimation());
}
}
public void onAnimationEnd() {
super.onAnimationEnd();
if (this.mListener != null) {
this.mListener.onAnimationEnd(getAnimation());
}
}
public void setBackgroundColorRes(int colorRes) {
setBackgroundColor(getContext().getResources().getColor(colorRes));
}
public void setBackgroundColor(int color) {
if (getBackground() instanceof ShapeDrawable) {
((ShapeDrawable) getBackground()).getPaint().setColor(color);
}
}
}