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Also prevents the snackbar from hiding the bottom of the list.

Closes #337

briar-android/src/org/briarproject/android/util/BriarRecyclerViewBehavior.java

@@ -0,0 +1,44 @@
+package org.briarproject.android.util;
+
+import android.content.Context;
+import android.support.design.widget.CoordinatorLayout;
+import android.support.design.widget.Snackbar;
+import android.util.AttributeSet;
+import android.view.View;
+
+public class BriarRecyclerViewBehavior
+		extends CoordinatorLayout.Behavior<BriarRecyclerView> {
+
+	public BriarRecyclerViewBehavior(Context context, AttributeSet attrs) {
+		super(context, attrs);
+	}
+
+	@Override
+	public boolean onDependentViewChanged(CoordinatorLayout parent,
+			BriarRecyclerView child, View dependency) {
+
+		// FIXME the below code works, but does not reset margin when snackbar is dismissed
+/*
+		int margin = 0;
+		if (dependency.isShown()) margin = dependency.getHeight();
+
+		// set snackbar height as bottom margin if it is shown
+		CoordinatorLayout.LayoutParams params =
+				(CoordinatorLayout.LayoutParams) child.getLayoutParams();
+		params.setMargins(0, 0, 0, margin);
+		child.setLayoutParams(params);
+
+		child.scrollToPosition(0);
+*/
+		return true;
+	}
+
+	@Override
+	public boolean layoutDependsOn(CoordinatorLayout parent,
+			BriarRecyclerView child, View dependency) {
+		// we only want to trigger the change
+		// only when the changes is from a snackbar
+		return dependency instanceof Snackbar.SnackbarLayout;
+	}
+
+}