Added special ScrollView with auto-scrolling feature

The ability to auto-scroll is disabled as soon as the user manually
scrolls around and re-enable when the user scrolls to the bottom.

diff --git a/src/frontends/android/src/org/strongswan/android/ui/LogScrollView.java b/src/frontends/android/src/org/strongswan/android/ui/LogScrollView.java
new file mode 100644 (file)
index 0000000..7eee820
--- /dev/null
+++ b/src/frontends/android/src/org/strongswan/android/ui/LogScrollView.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012 Giuliano Grassi
+ * Copyright (C) 2012 Ralf Sager
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+package org.strongswan.android.ui;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+import android.view.View;
+import android.widget.ScrollView;
+
+public class LogScrollView extends ScrollView
+{
+       private boolean mAutoScroll = true;
+
+       public LogScrollView(Context context)
+       {
+               super(context);
+       }
+
+       public LogScrollView(Context context, AttributeSet attrs)
+       {
+               super(context, attrs);
+       }
+
+       public LogScrollView(Context context, AttributeSet attrs, int defStyle)
+       {
+               super(context, attrs, defStyle);
+       }
+
+       @Override
+       public boolean onTouchEvent(MotionEvent ev)
+       {
+               /* disable auto-scrolling when the user starts scrolling around */
+               if (ev.getActionMasked() == MotionEvent.ACTION_DOWN)
+               {
+                       mAutoScroll = false;
+               }
+               return super.onTouchEvent(ev);
+       }
+
+       /**
+        * Call this to move newly added content into view by scrolling to the bottom.
+        * Nothing happens if auto-scrolling is disabled.
+        */
+       public void autoScroll()
+       {
+               if (mAutoScroll)
+               {
+                       fullScroll(View.FOCUS_DOWN);
+               }
+       }
+
+       @Override
+       protected void onScrollChanged(int l, int t, int oldl, int oldt)
+       {
+               super.onScrollChanged(l, t, oldl, oldt);
+               /* if the user scrolls to the bottom we enable auto-scrolling again */
+               if (t == getChildAt(getChildCount() - 1).getHeight() - getHeight())
+               {
+                       mAutoScroll = true;
+               }
+       }
+}