ShareInto: Fix crash getRecentFiles() on nullptr, closes #2672, by @gsantner

Author: gsantner

app/src/main/java/net/gsantner/opoc/frontend/base/GsActivityBase.java

@@ -11,7 +11,6 @@
 
 import static android.view.WindowManager.LayoutParams.FLAG_SECURE;
 
-import android.content.Context;
 import android.os.Bundle;
 import android.os.Handler;
 import android.view.View;

app/src/main/java/net/gsantner/opoc/frontend/base/GsPreferenceFragmentBase.java

@@ -145,12 +145,17 @@ public String getTitle() {
     protected int _defaultIconTintColor;
     protected GsContextUtils _cu;
 
+    @Override
+    public void onAttach(@NonNull Context context) {
+        super.onAttach(context);
+        _appSettings = getAppSettings(context);
+        _cu = GsContextUtils.instance;
+    }
+
     @Override
     @Deprecated
     public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
         Activity activity = getActivity();
-        _appSettings = getAppSettings(activity);
-        _cu = GsContextUtils.instance;
         getPreferenceManager().setSharedPreferencesName(getSharedPreferencesName());
         addPreferencesFromResource(getPreferenceResourceForInflation());
 

app/src/main/java/net/gsantner/opoc/frontend/filebrowser/GsFileBrowserFragment.java

@@ -38,7 +38,6 @@
 import androidx.recyclerview.widget.RecyclerView;
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
 
-import net.gsantner.markor.ApplicationObject;
 import net.gsantner.markor.R;
 import net.gsantner.markor.format.FormatRegistry;
 import net.gsantner.markor.frontend.FileInfoDialog;

app/src/main/java/net/gsantner/opoc/model/GsSharedPreferencesPropertyBackend.java

@@ -35,13 +35,11 @@ public boolean isAppCurrentVersionFirstStart(boolean doSet) {
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.SharedPreferences;
-import android.os.Build;
 import android.text.TextUtils;
 
 import androidx.annotation.ColorRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
-import androidx.core.content.ContextCompat;
 
 import java.io.File;
 import java.util.ArrayList;

app/src/main/java/net/gsantner/opoc/util/GsContextUtils.java

@@ -58,7 +58,6 @@
 import android.net.Uri;
 import android.os.Build;
 import android.os.Environment;
-import android.os.IBinder;
 import android.os.ParcelFileDescriptor;
 import android.os.SystemClock;
 import android.os.VibrationEffect;
@@ -90,10 +89,7 @@
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.Window;
-import android.view.WindowInsets;
-import android.view.WindowInsetsController;
 import android.view.WindowManager;
-import android.view.inputmethod.InputMethodManager;
 import android.webkit.MimeTypeMap;
 import android.webkit.WebView;
 import android.widget.ImageView;