GP-71: Prepping for source release.

Ghidra/Debug/ProposedUtils/src/main/java/docking/widgets/ExpanderArrowPanel.java

@@ -0,0 +1,155 @@
+/* ###
+ * IP: GHIDRA
+ *
+ * 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
+ * 
+ *      http://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 docking.widgets;
+
+import java.awt.*;
+import java.awt.event.*;
+import java.util.concurrent.CompletableFuture;
+
+import javax.swing.JPanel;
+
+import ghidra.util.datastruct.ListenerSet;
+
+public class ExpanderArrowPanel extends JPanel {
+	// TODO: Can I make this consistent with the UI LaF
+	protected final static Polygon ARROW =
+		new Polygon(new int[] { 5, -5, -5 }, new int[] { 0, -5, 5 }, 3);
+	protected final static Dimension SIZE = new Dimension(16, 16);
+	protected final static int ANIM_MILLIS = 80;
+	protected final static int FRAME_MILLIS = 30; // Approx 30 fps
+
+	private final ListenerSet<ExpanderArrowExpansionListener> listeners =
+		new ListenerSet<>(ExpanderArrowExpansionListener.class);
+
+	private boolean expanded = false;
+
+	private double animTheta;
+	private boolean animActive = false;
+	private long animTimeEnd;
+	private double animThetaEnd;
+	private double animThetaOverTimeRate;
+
+	private final MouseListener mouseListener = new MouseAdapter() {
+		@Override
+		public void mouseClicked(MouseEvent e) {
+			toggle();
+		}
+	};
+
+	{
+		addMouseListener(mouseListener);
+	}
+
+	public void addExpansionListener(ExpanderArrowExpansionListener listener) {
+		listeners.add(listener);
+	}
+
+	public void removeExpansionListener(ExpanderArrowExpansionListener listener) {
+		listeners.remove(listener);
+	}
+
+	protected synchronized void animateTheta(double destTheta) {
+		animTimeEnd = System.currentTimeMillis() + ANIM_MILLIS;
+		animThetaEnd = destTheta;
+		animThetaOverTimeRate = (destTheta - animTheta) / ANIM_MILLIS;
+		animActive = true;
+		scheduleNextFrame();
+	}
+
+	public void toggle() {
+		setExpanded(!expanded);
+	}
+
+	protected boolean fireChanging(boolean newExpanded) {
+		try {
+			listeners.fire.changing(newExpanded);
+		}
+		catch (ExpanderArrowExpansionVetoException e) {
+			return false;
+		}
+		return true;
+	}
+
+	protected void fireChanged() {
+		listeners.fire.changed(expanded);
+	}
+
+	public void setExpanded(boolean expanded) {
+		if (this.expanded == expanded) {
+			return;
+		}
+		if (!fireChanging(expanded)) {
+			return;
+		}
+		double destTheta = expanded ? Math.PI / 2 : 0;
+		animateTheta(destTheta);
+		this.expanded = expanded;
+		fireChanged();
+	}
+
+	public boolean isExpanded() {
+		return expanded;
+	}
+
+	@Override
+	protected void paintComponent(Graphics g) {
+		super.paintComponent(g);
+		Graphics2D g2 = (Graphics2D) g.create();
+		g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
+		g2.translate((double) SIZE.width / 2, (double) SIZE.height / 2);
+		g2.rotate(animTheta);
+		g2.fillPolygon(ARROW);
+
+		if (!animActive) {
+			return;
+		}
+		long time = System.currentTimeMillis();
+		double timeDiff = Math.max(0, animTimeEnd - time);
+		if (timeDiff != 0) {
+			double thetaDiff = timeDiff * animThetaOverTimeRate;
+			animTheta = animThetaEnd - thetaDiff;
+			scheduleNextFrame();
+			return;
+		}
+		animActive = false;
+		if (animTheta != animThetaEnd) {
+			animTheta = animThetaEnd;
+			scheduleNextFrame();
+		}
+	}
+
+	@Override
+	public Dimension getPreferredSize() {
+		return SIZE;
+	}
+
+	@Override
+	public Dimension getMinimumSize() {
+		return SIZE;
+	}
+
+	protected void scheduleNextFrame() {
+		CompletableFuture.runAsync(() -> {
+			try {
+				Thread.sleep(FRAME_MILLIS);
+			}
+			catch (InterruptedException e) {
+				// Whatever. Render early.
+			}
+			repaint();
+		});
+	}
+}