1.Tab layout

app/src/main/java/com/zane/smapiinstaller/MainActivity.java

@@ -63,7 +63,7 @@ public class MainActivity extends AppCompatActivity {
     private AppBarConfiguration mAppBarConfiguration;
 
     @BindView(R.id.launch)
-    FloatingActionButton buttonLaunch;
+    public FloatingActionButton buttonLaunch;
 
     @BindView(R.id.toolbar)
     Toolbar toolbar;
@@ -74,7 +74,9 @@ public class MainActivity extends AppCompatActivity {
     @BindView(R.id.nav_view)
     NavigationView navigationView;
 
-    private int currentFragment = R.id.nav_install;
+    private int currentFragment = R.id.nav_main;
+
+    public static MainActivity instance;
 
     private void requestPermissions() {
         if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE)
@@ -98,6 +100,7 @@ public class MainActivity extends AppCompatActivity {
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        instance = this;
         setContentView(R.layout.activity_main);
         ButterKnife.bind(this);
         AppConfig appConfig = ConfigUtils.getConfig((MainApplication) this.getApplication(), AppConfigKey.PRIVACY_POLICY_CONFIRM, false);
@@ -122,7 +125,7 @@ public class MainActivity extends AppCompatActivity {
         // Passing each menu ID as a set of Ids because each
         // menu should be considered as top level destinations.
         mAppBarConfiguration = new AppBarConfiguration.Builder(
-                R.id.nav_install, R.id.nav_config, R.id.nav_help, R.id.nav_download, R.id.nav_about)
+                R.id.nav_main, R.id.nav_config, R.id.nav_help, R.id.nav_download, R.id.nav_about)
                 .setOpenableLayout(drawer)
                 .build();
         final NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
@@ -406,5 +409,9 @@ public class MainActivity extends AppCompatActivity {
         DialogUtils.dismissDialog();
         super.onDestroy();
     }
+
+    public void setFloatingBarVisibility(boolean value) {
+        buttonLaunch.setVisibility(value ? View.VISIBLE: View.INVISIBLE);
+    }
 }
 

app/src/main/java/com/zane/smapiinstaller/ui/install/InstallFragment.java

@@ -20,6 +20,8 @@ import com.zane.smapiinstaller.constant.DialogAction;
 import com.zane.smapiinstaller.logic.ApkPatcher;
 import com.zane.smapiinstaller.logic.CommonLogic;
 import com.zane.smapiinstaller.logic.ModAssetsManager;
+import com.zane.smapiinstaller.ui.main.MainTabsFragment;
+import com.zane.smapiinstaller.ui.main.MainTabsFragmentDirections;
 import com.zane.smapiinstaller.utils.ConfigUtils;
 import com.zane.smapiinstaller.utils.DialogUtils;
 
@@ -128,7 +130,7 @@ public class InstallFragment extends Fragment {
                     DialogUtils.showConfirmDialog(root, R.string.error, StringUtils.firstNonBlank(patcher.getErrorMessage().get(), context.getString(R.string.failed_to_patch_game)), R.string.menu_download, R.string.cancel, (d, which) -> {
                         if (which == DialogAction.POSITIVE) {
                             NavController controller = Navigation.findNavController(installButton);
-                            controller.navigate(InstallFragmentDirections.actionNavInstallToNavDownload());
+                            controller.navigate(MainTabsFragmentDirections.actionNavMainToNavDownload());
                         }
                     });
                 } else {
@@ -198,7 +200,7 @@ public class InstallFragment extends Fragment {
                     DialogUtils.showConfirmDialog(root, R.string.error, StringUtils.firstNonBlank(patcher.getErrorMessage().get(), context.getString(R.string.failed_to_patch_game)), R.string.menu_download, R.string.cancel, (d, which) -> {
                         if (which == DialogAction.POSITIVE) {
                             NavController controller = Navigation.findNavController(installButton);
-                            controller.navigate(InstallFragmentDirections.actionNavInstallToNavDownload());
+                            controller.navigate(MainTabsFragmentDirections.actionNavMainToNavDownload());
                         }
                     });
                 } else {

app/src/main/java/com/zane/smapiinstaller/ui/main/MainTabPagerAdapter.java

@@ -0,0 +1,75 @@
+package com.zane.smapiinstaller.ui.main;
+
+import android.os.Bundle;
+
+import com.zane.smapiinstaller.R;
+import com.zane.smapiinstaller.ui.about.AboutFragment;
+import com.zane.smapiinstaller.ui.config.ConfigFragment;
+import com.zane.smapiinstaller.ui.download.DownloadableContentFragment;
+import com.zane.smapiinstaller.ui.help.HelpFragment;
+import com.zane.smapiinstaller.ui.install.InstallFragment;
+
+import org.jetbrains.annotations.NotNull;
+
+import androidx.fragment.app.Fragment;
+import androidx.viewpager2.adapter.FragmentStateAdapter;
+
+class MainTabPagerAdapter extends FragmentStateAdapter {
+    private Fragment fragment;
+
+    public MainTabPagerAdapter(Fragment fragment) {
+        super(fragment);
+        this.fragment = fragment;
+    }
+
+    @NotNull
+    @Override
+    public Fragment createFragment(int position) {
+        Bundle args = new Bundle();
+        Fragment fragment;
+        switch (position){
+            case 1:
+                fragment = new ConfigFragment();
+                fragment.setArguments(args);
+                return fragment;
+            case 2:
+                fragment = new DownloadableContentFragment();
+                fragment.setArguments(args);
+                return fragment;
+            case 3:
+                fragment = new HelpFragment();
+                fragment.setArguments(args);
+                return fragment;
+            case 4:
+                fragment = new AboutFragment();
+                fragment.setArguments(args);
+                return fragment;
+            case 0:
+            default:
+                fragment = new InstallFragment();
+                fragment.setArguments(args);
+                return fragment;
+        }
+    }
+
+    public String getTitle(int position) {
+        switch (position){
+            case 1:
+                return fragment.getString(R.string.menu_config);
+            case 2:
+                return fragment.getString(R.string.menu_download);
+            case 3:
+                return fragment.getString(R.string.menu_help);
+            case 4:
+                return fragment.getString(R.string.menu_about);
+            case 0:
+            default:
+                return fragment.getString(R.string.menu_install);
+        }
+    }
+
+    @Override
+    public int getItemCount() {
+        return 5;
+    }
+}

app/src/main/java/com/zane/smapiinstaller/ui/main/MainTabsFragment.java

@@ -0,0 +1,59 @@
+package com.zane.smapiinstaller.ui.main;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import com.google.android.material.tabs.TabLayout;
+import com.google.android.material.tabs.TabLayoutMediator;
+import com.zane.smapiinstaller.MainActivity;
+import com.zane.smapiinstaller.R;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.fragment.app.Fragment;
+import androidx.viewpager2.widget.ViewPager2;
+import butterknife.BindView;
+import butterknife.ButterKnife;
+
+/**
+ * @author Zane
+ */
+public class MainTabsFragment extends Fragment {
+
+    @BindView(R.id.main_tab_layout)
+    TabLayout tabLayout;
+    @BindView(R.id.main_pager)
+    ViewPager2 viewPager;
+
+    @Nullable
+    @Override
+    public View onCreateView(@NonNull LayoutInflater inflater,
+                             @Nullable ViewGroup container,
+                             @Nullable Bundle savedInstanceState) {
+        View view = inflater.inflate(R.layout.fragment_main, container, false);
+        ButterKnife.bind(this, view);
+        return view;
+    }
+
+    @Override
+    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
+        MainTabPagerAdapter pagerAdapter = new MainTabPagerAdapter(this);
+        viewPager.setAdapter(pagerAdapter);
+        new TabLayoutMediator(tabLayout, viewPager,
+                (tab, position) -> tab.setText(pagerAdapter.getTitle(position))
+        ).attach();
+        viewPager.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
+            @Override
+            public void onPageSelected(int position) {
+                super.onPageSelected(position);
+                if (position >= 3) {
+                    MainActivity.instance.setFloatingBarVisibility(false);
+                } else {
+                    MainActivity.instance.setFloatingBarVisibility(true);
+                }
+            }
+        });
+    }
+}

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

@@ -0,0 +1,17 @@
+<?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="match_parent"
+    android:orientation="vertical">
+    <com.google.android.material.tabs.TabLayout
+        android:id="@+id/main_tab_layout"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+    </com.google.android.material.tabs.TabLayout>
+    <androidx.viewpager2.widget.ViewPager2
+        android:id="@+id/main_pager"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
+    </androidx.viewpager2.widget.ViewPager2>
+</LinearLayout>

app/src/main/res/menu/activity_main_drawer.xml

@@ -5,9 +5,9 @@
 
     <group android:checkableBehavior="single">
         <item
-            android:id="@+id/nav_install"
+            android:id="@+id/nav_main"
             android:icon="@drawable/add"
-            android:title="@string/menu_install" />
+            android:title="@string/nav_header_title" />
         <item
             android:id="@+id/nav_config"
             android:icon="@drawable/edit"

app/src/main/res/navigation/mobile_navigation.xml

@@ -3,16 +3,21 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/mobile_navigation"
-    app:startDestination="@+id/nav_install">
+    app:startDestination="@+id/nav_main">
-
     <fragment
-        android:id="@+id/nav_install"
+        android:id="@+id/nav_main"
+        android:name="com.zane.smapiinstaller.ui.main.MainTabsFragment"
+        android:label="@string/nav_header_title"
+        tools:layout="@layout/fragment_main">
+        <action
+            android:id="@+id/action_nav_main_to_nav_download"
+            app:destination="@id/nav_download" />
+    </fragment>
+    <fragment
+        android:id="@+id/install_fragment"
         android:name="com.zane.smapiinstaller.ui.install.InstallFragment"
         android:label="@string/menu_install"
         tools:layout="@layout/fragment_install">
-        <action
-            android:id="@+id/action_nav_install_to_nav_download"
-            app:destination="@id/nav_download" />
     </fragment>
     <fragment
         android:id="@+id/config_edit_fragment"