From d9081ff19efdb2227f4c22652ed9fc39ac7a0327 Mon Sep 17 00:00:00 2001
From: Robert Scott <code@humanleg.org.uk>
Date: Sun, 8 Oct 2017 11:02:15 +0100
Subject: [PATCH 1/3] add PopupMenuButton: a button for triggering the
 appearance of a JPopupMenu when activated

---
 .../josm/gui/widgets/PopupMenuButton.java          | 116 +++++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 src/org/openstreetmap/josm/gui/widgets/PopupMenuButton.java

diff --git a/src/org/openstreetmap/josm/gui/widgets/PopupMenuButton.java b/src/org/openstreetmap/josm/gui/widgets/PopupMenuButton.java
new file mode 100644
index 0000000..664e477
--- /dev/null
+++ b/src/org/openstreetmap/josm/gui/widgets/PopupMenuButton.java
@@ -0,0 +1,116 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.gui.widgets;
+
+import java.awt.Color;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Point;
+import java.awt.Rectangle;
+import java.awt.event.ActionListener;
+import java.awt.event.ActionEvent;
+import java.awt.geom.Path2D;
+
+
+import javax.swing.Action;
+import javax.swing.Icon;
+import javax.swing.JButton;
+import javax.swing.JPopupMenu;
+
+
+/**
+ * Button triggering the appearance of a JPopupMenu when activated
+ */
+public class PopupMenuButton extends JButton implements ActionListener {
+    private JPopupMenu menu;
+
+    /* Pass-throughs to JButton's constructors */
+
+    public PopupMenuButton() {
+        super();
+        this.initialize();
+    }
+
+    public PopupMenuButton(Action a) {
+        super(a);
+        this.initialize();
+    }
+
+    public PopupMenuButton(Icon i) {
+        super(i);
+        this.initialize();
+    }
+
+    public PopupMenuButton(String t, Icon i) {
+        super(t, i);
+        this.initialize();
+    }
+
+    /* Pass-throughs to JButton's constructors with addition of JPopupMenu */
+
+    public PopupMenuButton(JPopupMenu m) {
+        super();
+        this.initialize(m);
+    }
+
+    public PopupMenuButton(Action a, JPopupMenu m) {
+        super(a);
+        this.initialize(m);
+    }
+
+    public PopupMenuButton(Icon i, JPopupMenu m) {
+        super(i);
+        this.initialize(m);
+    }
+
+    public PopupMenuButton(String t, Icon i, JPopupMenu m) {
+        super(t, i);
+        this.initialize(m);
+    }
+
+
+    private void initialize(JPopupMenu m) {
+        this.menu = m;
+        this.initialize();
+    }
+
+    private void initialize() {
+        this.addActionListener(this);
+    }
+
+
+    public JPopupMenu getPopupMenu() {
+        return this.menu;
+    }
+
+    public void setPopupMenu(JPopupMenu m) {
+        this.menu = m;
+    }
+
+
+    @Override
+    public void actionPerformed(ActionEvent e) {
+        this.menu.show(this, 0, this.getHeight());
+    }
+
+
+    @Override
+    public void paint(Graphics g) {
+        super.paint(g);
+        Graphics2D g2d = (Graphics2D)g;
+
+        //
+        // paint small arrow in bottom right corner
+        //
+        Rectangle clip = g2d.getClipBounds();
+        Point br = new Point(clip.x + clip.width, clip.y + clip.height);  // "bottom right"
+
+        Path2D p = new Path2D.Float();
+        p.moveTo(br.x - 7, br.y - 4);
+        p.lineTo(br.x - 1, br.y - 4);
+        p.lineTo(br.x - 4, br.y - 1);
+        p.closePath();
+
+        g2d.setPaint(Color.BLACK);
+        g2d.fill(p);
+    }
+}
-- 
2.1.4