1 files changed, 63 insertions, 0 deletions
diff --git a/app/src/main/java/se/leap/bitmaskclient/providersetup/fragments/BaseSetupFragment.java b/app/src/main/java/se/leap/bitmaskclient/providersetup/fragments/BaseSetupFragment.java
new file mode 100644
index 00000000..8012fe76
--- /dev/null
+++ b/app/src/main/java/se/leap/bitmaskclient/providersetup/fragments/BaseSetupFragment.java
@@ -0,0 +1,63 @@
+package se.leap.bitmaskclient.providersetup.fragments;
+
+import android.content.Context;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.Fragment;
+import androidx.viewpager2.widget.ViewPager2;
+
+import se.leap.bitmaskclient.providersetup.activities.SetupActivityCallback;
+
+public class BaseSetupFragment extends Fragment {
+
+    SetupActivityCallback setupActivityCallback;
+    private boolean callFragmentSelected = false;
+    private final ViewPager2.OnPageChangeCallback viewPagerCallback = new ViewPager2.OnPageChangeCallback() {
+        @Override
+        public void onPageSelected(int position) {
+            super.onPageSelected(position);
+            if (position == BaseSetupFragment.this.position) {
+                handleCallFragmentSelected();
+            } else {
+                callFragmentSelected = false;
+            }
+        }
+    };
+    private final int position;
+
+    public BaseSetupFragment(int position) {
+        this.position = position;
+    }
+
+    @Override
+    public void onAttach(@NonNull Context context) {
+        super.onAttach(context);
+        if (getActivity() instanceof SetupActivityCallback) {
+            setupActivityCallback = (SetupActivityCallback) getActivity();
+            setupActivityCallback.registerOnPageChangeCallback(viewPagerCallback);
+            if (setupActivityCallback.getCurrentPosition() == position) {
+                handleCallFragmentSelected();
+            }
+        } else {
+            throw new IllegalStateException("These setup fragments are closely coupled to SetupActivityCallback interface. Activities instantiating them are required to implement the interface");
+        }
+    }
+
+    private void handleCallFragmentSelected() {
+        if (!callFragmentSelected) {
+            callFragmentSelected = true;
+            onFragmentSelected();
+        }
+    }
+
+    @Override
+    public void onDetach() {
+        super.onDetach();
+        setupActivityCallback.removeOnPageChangeCallback(viewPagerCallback);
+        setupActivityCallback = null;
+    }
+
+    public void onFragmentSelected() {
+
+    }
+}