AnimatedBorder

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatAbstractIcon.java

@@ -69,7 +69,13 @@ public void paintIcon( Component c, Graphics g, int x, int y ) {
 		}
 	}
 
-	protected abstract void paintIcon( Component c, Graphics2D g2 );
+	/**
+	 * Paint the icon at {@code [0,0]} location.
+	 * <p>
+	 * The given graphics context is scaled.
+	 * Use unscaled coordinates, width and height for painting.
+	 */
+	protected abstract void paintIcon( Component c, Graphics2D g );
 
 	@Override
 	public int getIconWidth() {

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatAnimatedIcon.java

@@ -21,6 +21,7 @@
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import com.formdev.flatlaf.util.AnimatedIcon;
+import com.formdev.flatlaf.util.AnimatedPainter;
 
 /**
  * Base class for animated icons that scales width and height, creates and initializes
@@ -30,7 +31,7 @@
  * <p>
  * This class does not store any state information (needed for animation) in its instance.
  * Instead a client property is set on the painted component.
- * This makes it possible to use a share icon instance for multiple components.
+ * This makes it possible to use a shared icon instance for multiple components.
  *
  * @author Karl Tauber
  */
@@ -45,11 +46,34 @@ public FlatAnimatedIcon( int width, int height, Color color ) {
 	@Override
 	public void paintIcon( Component c, Graphics g, int x, int y ) {
 		super.paintIcon( c, g, x, y );
-		AnimatedIcon.AnimationSupport.saveIconLocation( this, c, x, y );
+		AnimatedPainter.saveRepaintLocation( this, c, x, y );
 	}
 
 	@Override
 	protected void paintIcon( Component c, Graphics2D g ) {
-		AnimatedIcon.AnimationSupport.paintIcon( this, c, g, 0, 0 );
+		paintWithAnimation( c, g, 0, 0, getIconWidth(), getIconHeight() );
 	}
+
+	/**
+	 * Delegates painting to {@link #paintIconAnimated(Component, Graphics2D, float[])}.
+	 * Ignores the given bounds because {@code [x,y]} are always {@code [0,0]} and
+	 * {@code [width,height]} are scaled, but painting code should use unscaled width
+	 * and height because given graphics context is scaled.
+	 *
+	 * @since 2
+	 */
+	@Override
+	public void paintAnimated( Component c, Graphics2D g, int x, int y, int width, int height, float[] animatedValues ) {
+		paintIconAnimated( c, g, animatedValues );
+	}
+
+	/**
+	 * Paint the icon at {@code 0,0} location.
+	 * <p>
+	 * The given graphics context is scaled.
+	 * Use unscaled coordinates, width and height for painting.
+	 *
+	 * @since 2
+	 */
+	protected abstract void paintIconAnimated( Component c, Graphics2D g, float[] animatedValues );
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/util/AnimatedBorder.java

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2021 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.util;
+
+import java.awt.Component;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import javax.swing.JComponent;
+import javax.swing.border.Border;
+
+/**
+ * Border that automatically animates painting on component value changes.
+ * <p>
+ * {@link #getValues(Component)} returns the value(s) of the component.
+ * If the value(s) have changed, then {@link #paintAnimated(Component, Graphics2D, int, int, int, int, float[])}
+ * is invoked multiple times with animated value(s) (from old value(s) to new value(s)).
+ * If {@link #getValues(Component)} returns multiple values, then each value gets its own independent animation.
+ * <p>
+ * Example for an animated border:
+ * <pre>
+ * private class MyAnimatedBorder
+ *     implements AnimatedBorder
+ * {
+ *     &#64;Override
+ *     public void paintAnimated( Component c, Graphics2D g, int x, int y, int width, int height, float[] animatedValues ) {
+ *         int lh = UIScale.scale( 2 );
+ *
+ *         g.setColor( Color.blue );
+ *         g.fillRect( x, y + height - lh, Math.round( width * animatedValues[0] ), lh );
+ *     }
+ *
+ *     &#64;Override
+ *     public float[] getValues( Component c ) {
+ *         return new float[] { c.isFocusOwner() ? 1 : 0 };
+ *     }
+ *
+ *     &#64;Override
+ *     public Insets getBorderInsets( Component c ) {
+ *         return UIScale.scale( new Insets( 4, 4, 4, 4 ) );
+ *     }
+ *
+ *     &#64;Override public boolean isBorderOpaque() { return false; }
+ * }
+ *
+ * // sample usage
+ * JTextField textField = new JTextField();
+ * textField.setBorder( new MyAnimatedBorder() );
+ * </pre>
+ *
+ * Animation works only if the component passed to {@link #paintBorder(Component, Graphics, int, int, int, int)}
+ * is a instance of {@link JComponent}.
+ * A client property is set on the component to store the animation state.
+ *
+ * @author Karl Tauber
+ * @since 2
+ */
+public interface AnimatedBorder
+	extends Border, AnimatedPainter
+{
+	/**
+	 * Invokes {@link #paintWithAnimation(Component, Graphics, int, int, int, int)}.
+	 */
+	@Override
+	default void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
+		paintWithAnimation( c, g, x, y, width, height );
+	}
+}