1 files changed, 45 insertions, 0 deletions
diff --git a/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java b/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java
new file mode 100644
index 00000000..9e188bc0
--- /dev/null
+++ b/app/src/main/java/com/wireguard/android/fragment/BaseFragment.java
@@ -0,0 +1,45 @@
+package com.wireguard.android.fragment;
+
+import android.app.Fragment;
+import android.content.Context;
+
+import com.wireguard.android.activity.BaseActivity;
+import com.wireguard.android.activity.BaseActivity.OnSelectedTunnelChangedListener;
+import com.wireguard.android.model.Tunnel;
+
+/**
+ * Base class for fragments that need to know the currently-selected tunnel. Only does anything when
+ * attached to a {@code BaseActivity}.
+ */
+
+public abstract class BaseFragment extends Fragment implements OnSelectedTunnelChangedListener {
+    private BaseActivity activity;
+
+    protected Tunnel getSelectedTunnel() {
+        return activity != null ? activity.getSelectedTunnel() : null;
+    }
+
+    @Override
+    public void onAttach(final Context context) {
+        super.onAttach(context);
+        if (context instanceof BaseActivity) {
+            activity = (BaseActivity) context;
+            activity.addOnSelectedTunnelChangedListener(this);
+        } else {
+            activity = null;
+        }
+    }
+
+    @Override
+    public void onDetach() {
+        if (activity != null)
+            activity.removeOnSelectedTunnelChangedListener(this);
+        activity = null;
+        super.onDetach();
+    }
+
+    protected void setSelectedTunnel(final Tunnel tunnel) {
+        if (activity != null)
+            activity.setSelectedTunnel(tunnel);
+    }
+}