Start working on ability to remove groups

app/src/main/AndroidManifest.xml

@@ -54,5 +54,10 @@
             android:label="Manage key slots"
             android:theme="@style/AppTheme.TransparentActionBar">
         </activity>
+        <activity
+            android:name=".ui.GroupManagerActivity"
+            android:label="Manage groups"
+            android:theme="@style/AppTheme.TransparentActionBar">
+        </activity>
     </application>
 </manifest>

app/src/main/java/me/impy/aegis/db/DatabaseManager.java

@@ -172,6 +172,17 @@ public class DatabaseManager {
         return groups;
     }
 
+    public void removeGroup(String groupName) {
+        TreeSet<String> groups = new TreeSet<>(Collator.getInstance());
+        for (DatabaseEntry entry : getEntries()) {
+            String group = entry.getGroup();
+            if (group != null && group.equals(groupName)) {
+                entry.setGroup(null);
+                _db.replaceEntry(entry);
+            }
+        }
+    }
+
     public DatabaseFileCredentials getCredentials() {
         assertState(false, true);
         return _creds;

app/src/main/java/me/impy/aegis/ui/GroupManagerActivity.java

@@ -0,0 +1,58 @@
+package me.impy.aegis.ui;
+
+import android.os.Bundle;
+
+import java.util.TreeSet;
+
+import androidx.appcompat.app.ActionBar;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
+import me.impy.aegis.AegisApplication;
+import me.impy.aegis.R;
+import me.impy.aegis.db.DatabaseFileCredentials;
+import me.impy.aegis.db.DatabaseManager;
+import me.impy.aegis.db.slots.Slot;
+import me.impy.aegis.ui.views.GroupAdapter;
+import me.impy.aegis.ui.views.SlotAdapter;
+
+public class GroupManagerActivity extends AegisActivity implements GroupAdapter.Listener {
+    private AegisApplication _app;
+    private DatabaseManager _db;
+    private GroupAdapter _adapter;
+
+    TreeSet<String> groups;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_groups);
+
+        _app = (AegisApplication) getApplication();
+        _db = _app.getDatabaseManager();
+
+        groups = _db.getGroups();
+
+        ActionBar bar = getSupportActionBar();
+        bar.setHomeAsUpIndicator(R.drawable.ic_close);
+        bar.setDisplayHomeAsUpEnabled(true);
+
+        // set up the recycler view
+        _adapter = new GroupAdapter(this);
+        RecyclerView slotsView = findViewById(R.id.list_slots);
+        LinearLayoutManager layoutManager = new LinearLayoutManager(this);
+        slotsView.setLayoutManager(layoutManager);
+        slotsView.setAdapter(_adapter);
+        slotsView.setNestedScrollingEnabled(false);
+
+        // load the slots and masterKey
+        for (String group : groups) {
+            _adapter.addGroup(group);
+        }
+    }
+
+    @Override
+    public void onRemoveGroup(String group) {
+        _db.removeGroup(group);
+        groups.remove(group);
+    }
+}

app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java

@@ -67,6 +67,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat {
     private SwitchPreference _fingerprintPreference;
     private Preference _setPasswordPreference;
     private Preference _slotsPreference;
+    private Preference _groupsPreference;
 
     @Override
     public void onCreatePreferencesFix(Bundle savedInstanceState, String rootKey) {
@@ -208,6 +209,15 @@ public class PreferencesFragment extends PreferenceFragmentCompat {
             }
         });
 
+        _groupsPreference = findPreference("pref_groups");
+        _groupsPreference.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
+            @Override
+            public boolean onPreferenceClick(Preference preference) {
+                Intent intent = new Intent(getActivity(), GroupManagerActivity.class);
+                startActivity(intent);
+                return true;
+            }
+        });
         updateEncryptionPreferences();
     }
 

app/src/main/java/me/impy/aegis/ui/views/GroupAdapter.java

@@ -0,0 +1,62 @@
+package me.impy.aegis.ui.views;
+
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import java.util.ArrayList;
+
+import androidx.recyclerview.widget.RecyclerView;
+import me.impy.aegis.R;
+import me.impy.aegis.db.slots.Slot;
+
+public class GroupAdapter extends RecyclerView.Adapter<GroupHolder> {
+    private GroupAdapter.Listener _listener;
+    private ArrayList<String> _groups;
+
+    public GroupAdapter(GroupAdapter.Listener listener) {
+        _listener = listener;
+        _groups = new ArrayList<>();
+    }
+
+    public void addGroup(String group) {
+        _groups.add(group);
+
+        int position = getItemCount() - 1;
+        if (position == 0) {
+            notifyDataSetChanged();
+        } else {
+            notifyItemInserted(position);
+        }
+    }
+
+    public void removeGroup(String group) {
+        int position = _groups.indexOf(group);
+        _groups.remove(position);
+        notifyItemRemoved(position);
+    }
+
+    @Override
+    public GroupHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.card_slot, parent, false);
+        return new GroupHolder(view);
+    }
+
+    @Override
+    public void onBindViewHolder(GroupHolder holder, int position) {
+        holder.setData(_groups.get(position));
+        holder.setOnDeleteClickListener(v -> {
+            int position12 = holder.getAdapterPosition();
+            _listener.onRemoveGroup(_groups.get(position12));
+        });
+    }
+
+    @Override
+    public int getItemCount() {
+        return _groups.size();
+    }
+
+    public interface Listener {
+        void onRemoveGroup(String group);
+    }
+}

app/src/main/java/me/impy/aegis/ui/views/GroupHolder.java

@@ -0,0 +1,35 @@
+package me.impy.aegis.ui.views;
+
+import androidx.recyclerview.widget.RecyclerView;
+import android.view.View;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+import me.impy.aegis.R;
+import me.impy.aegis.crypto.KeyStoreHandle;
+import me.impy.aegis.crypto.KeyStoreHandleException;
+import me.impy.aegis.db.slots.FingerprintSlot;
+import me.impy.aegis.db.slots.PasswordSlot;
+import me.impy.aegis.db.slots.RawSlot;
+import me.impy.aegis.db.slots.Slot;
+import me.impy.aegis.helpers.FingerprintHelper;
+
+public class GroupHolder extends RecyclerView.ViewHolder {
+    private TextView _slotName;
+    private ImageView _buttonDelete;
+
+    public GroupHolder(final View view) {
+        super(view);
+        _slotName = view.findViewById(R.id.text_slot_name);
+        _buttonDelete = view.findViewById(R.id.button_delete);
+    }
+
+    public void setData(String groupName) {
+        _slotName.setText(groupName);
+    }
+
+    public void setOnDeleteClickListener(View.OnClickListener listener) {
+        _buttonDelete.setOnClickListener(listener);
+    }
+}

app/src/main/res/layout/activity_groups.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:fitsSystemWindows="true"
+    tools:context="me.impy.aegis.ui.GroupManagerActivity">
+
+    <androidx.core.widget.NestedScrollView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical">
+
+            <androidx.recyclerview.widget.RecyclerView
+                android:id="@+id/list_slots"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:scrollbars="vertical"/>
+
+        </LinearLayout>
+
+    </androidx.core.widget.NestedScrollView>
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

app/src/main/res/layout/card_group.xml

@@ -0,0 +1,70 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="horizontal">
+
+    <LinearLayout
+        android:id="@+id/button_edit"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_weight="1"
+        android:clickable="true"
+        android:focusable="true"
+        android:orientation="horizontal"
+        android:paddingStart="10dp"
+        android:paddingEnd="10dp"
+        android:paddingTop="12.5dp"
+        android:paddingBottom="12.5dp"
+        android:foreground="?android:attr/selectableItemBackground">
+
+        <LinearLayout
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:orientation="vertical">
+
+            <TextView
+                android:id="@+id/text_group_name"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="Group name"
+                android:textAppearance="?android:attr/textAppearanceMedium"
+                android:textColor="?android:attr/textColorPrimary" />
+
+            <TextView
+                android:id="@+id/text_slot_used"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="5dp"
+                android:text="... entries"
+                android:visibility="visible" />
+
+        </LinearLayout>
+
+    </LinearLayout>
+
+    <View
+        android:layout_width="1dp"
+        android:layout_height="match_parent"
+        android:background="@android:color/darker_gray"
+        android:paddingStart="15dp"
+        android:paddingEnd="15dp"
+        android:layout_marginTop="12.5dp"
+        android:layout_marginBottom="12.5dp"/>
+
+    <ImageView
+        android:id="@+id/button_delete"
+        android:layout_width="wrap_content"
+        android:layout_height="match_parent"
+        android:clickable="true"
+        android:focusable="true"
+        android:foreground="?android:attr/selectableItemBackground"
+        android:paddingStart="15dp"
+        android:paddingTop="12.5dp"
+        android:paddingEnd="15dp"
+        android:paddingBottom="12.5dp"
+        android:src="@drawable/ic_delete_black_24dp"
+        android:tint="?attr/iconColorPrimary" />
+
+</LinearLayout>

app/src/main/res/values/strings.xml

@@ -142,4 +142,6 @@
     <string name="new_group">New group...</string>
     <string name="enter_group_name">Enter a group name</string>
     <string name="group_name_hint">Group name</string>
+    <string name="preference_manage_groups">Edit groups</string>
+    <string name="preference_manage_groups_summary">Manage and delete your groups here</string>
 </resources>

app/src/main/res/xml/preferences.xml

@@ -20,6 +20,12 @@
             android:title="@string/pref_account_name_title"
             android:summary="@string/pref_account_name_summary"
             app:iconSpaceReserved="false"/>
+
+        <Preference
+            android:key="pref_groups"
+            android:title="@string/preference_manage_groups"
+            android:summary="@string/preference_manage_groups_summary"
+            app:iconSpaceReserved="false"/>
     </PreferenceCategory>
 
     <PreferenceCategory