X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=altosuilib%2FGrabNDrag.java;fp=altosuilib%2FGrabNDrag.java;h=4426f7a3de35fe436ae2d9211c4af350ed4c6ebe;hb=3cf030fffffd223c3717011e03aac82346295d71;hp=0000000000000000000000000000000000000000;hpb=607fbb01710be1cb263625337f5be3d0fb48d5e7;p=fw%2Faltos

diff --git a/altosuilib/GrabNDrag.java b/altosuilib/GrabNDrag.java
new file mode 100644
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+++ b/altosuilib/GrabNDrag.java
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+/*
+ * Copyright © 2010 Anthony Towns <aj@erisian.com.au>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+package org.altusmetrum.altosuilib_2;
+
+import java.awt.*;
+import java.awt.event.*;
+import javax.swing.*;
+import javax.swing.event.MouseInputAdapter;
+
+class GrabNDrag extends MouseInputAdapter {
+	private JComponent scroll;
+	private Point startPt = new Point();
+
+	public GrabNDrag(JComponent scroll) {
+		this.scroll = scroll;
+		scroll.addMouseMotionListener(this);
+		scroll.addMouseListener(this);
+		scroll.setAutoscrolls(true);
+	}
+
+	public static boolean grab_n_drag(MouseEvent e) {
+		return e.getModifiers() == InputEvent.BUTTON1_MASK;
+	}
+
+	public void mousePressed(MouseEvent e) {
+		if (grab_n_drag(e))
+			startPt.setLocation(e.getPoint());
+	}
+	public void mouseDragged(MouseEvent e) {
+		if (grab_n_drag(e)) {
+			int xd = e.getX() - startPt.x;
+			int yd = e.getY() - startPt.y;
+
+			Rectangle r = scroll.getVisibleRect();
+			r.x -= xd;
+			r.y -= yd;
+			scroll.scrollRectToVisible(r);
+		}
+	}
+}