1 files changed, 95 insertions, 0 deletions
diff --git a/src/org/cyanogenmod/audiofx/audiofx/preset/InfinitePagerAdapter.java b/src/org/cyanogenmod/audiofx/audiofx/preset/InfinitePagerAdapter.java
new file mode 100644
index 0000000..71811f4
--- /dev/null
+++ b/src/org/cyanogenmod/audiofx/audiofx/preset/InfinitePagerAdapter.java
@@ -0,0 +1,95 @@
+package com.cyngn.audiofx.preset;
+
+import android.os.Parcelable;
+import android.support.v4.view.PagerAdapter;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewGroup;
+
+/**
+ * A PagerAdapter that wraps around another PagerAdapter to handle paging wrap-around.
+ */
+public class InfinitePagerAdapter extends PagerAdapter {
+
+    private static final String TAG = "InfinitePagerAdapter";
+    private static final boolean DEBUG = false;
+
+    private PagerAdapter adapter;
+
+    public InfinitePagerAdapter(PagerAdapter adapter) {
+        this.adapter = adapter;
+    }
+
+    @Override
+    public int getCount() {
+        // warning: scrolling to very high values (1,000,000+) results in
+        // strange drawing behaviour
+        return Integer.MAX_VALUE;
+    }
+
+    /**
+     * @return the {@link #getCount()} result of the wrapped adapter
+     */
+    public int getRealCount() {
+        return adapter.getCount();
+    }
+
+    @Override
+    public Object instantiateItem(ViewGroup container, int position) {
+        int virtualPosition = position % getRealCount();
+        debug("instantiateItem: real position: " + position);
+        debug("instantiateItem: virtual position: " + virtualPosition);
+
+        // only expose virtual position to the inner adapter
+        return adapter.instantiateItem(container, virtualPosition);
+    }
+
+    @Override
+    public void destroyItem(ViewGroup container, int position, Object object) {
+        int virtualPosition = position % getRealCount();
+        debug("destroyItem: real position: " + position);
+        debug("destroyItem: virtual position: " + virtualPosition);
+
+        // only expose virtual position to the inner adapter
+        adapter.destroyItem(container, virtualPosition, object);
+    }
+
+    /*
+     * Delegate rest of methods directly to the inner adapter.
+     */
+
+    @Override
+    public void finishUpdate(ViewGroup container) {
+        adapter.finishUpdate(container);
+    }
+
+    @Override
+    public boolean isViewFromObject(View view, Object object) {
+        return adapter.isViewFromObject(view, object);
+    }
+
+    @Override
+    public void restoreState(Parcelable bundle, ClassLoader classLoader) {
+        adapter.restoreState(bundle, classLoader);
+    }
+
+    @Override
+    public Parcelable saveState() {
+        return adapter.saveState();
+    }
+
+    @Override
+    public void startUpdate(ViewGroup container) {
+        adapter.startUpdate(container);
+    }
+
+    /*
+     * End delegation
+     */
+
+    private void debug(String message) {
+        if (DEBUG) {
+            Log.d(TAG, message);
+        }
+    }
+}
+\ No newline at end of file