v0.7.5e: added scroll wheel support

SPD-classes/src/main/java/com/watabou/noosa/ScrollArea.java

@@ -0,0 +1,58 @@
+/*
+ * Pixel Dungeon
+ * Copyright (C) 2012-2015 Oleg Dolya
+ *
+ * Shattered Pixel Dungeon
+ * Copyright (C) 2014-2019 Evan Debenham
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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, see <http://www.gnu.org/licenses/>
+ */
+
+package com.watabou.noosa;
+
+import com.watabou.input.ScrollEvent;
+import com.watabou.utils.Signal;
+
+//pointer area with additional support for detecting scrolling events
+public class ScrollArea extends PointerArea {
+	
+	public ScrollArea( Visual target ){
+		super( target );
+		ScrollEvent.addScrollListener( scrollListener );
+	}
+	
+	public ScrollArea(float x, float y, float width, float height ) {
+		super( x, y, width, height );
+		ScrollEvent.addScrollListener( scrollListener );
+	}
+	
+	private Signal.Listener<ScrollEvent> scrollListener = new Signal.Listener<ScrollEvent>() {
+		@Override
+		public boolean onSignal(ScrollEvent event) {
+			if (event != null && target.overlapsScreenPoint( (int)event.pos.x, (int)event.pos.y )){
+				onScroll( event );
+				return true;
+			}
+			return false;
+		}
+	};
+	
+	protected void onScroll( ScrollEvent event ){ }
+	
+	@Override
+	public void destroy() {
+		super.destroy();
+		ScrollEvent.removeScrollListener( scrollListener );
+	}
+}