Remove SinglePermission

app/src/main/java/rs/chir/invtracker/client/EditItemFragment.java

@@ -29,7 +29,6 @@ import java.net.URI;
 import rs.chir.compat.java.util.Optional;
 import rs.chir.invtracker.client.databinding.FragmentEditItemBinding;
 import rs.chir.invtracker.model.TrackedItem;
-import rs.chir.invtracker.utils.SinglePermission;
 
 /**
  * The Item editing and creation interface.
@@ -145,14 +144,11 @@ public class EditItemFragment extends FragmentBase<FragmentEditItemBinding> {
             this.getBinding().progressBar.setVisibility(View.VISIBLE);
             this.subscribe(this.getClient().flatMap(client -> client.getObject(mId)), this::prefillItem);
         }
-        // On older versions of android, we need to request the camera permission to ask the camera for a picture
-        // Hide the camera button if we don't have the permission
-        if (!this.hasPermission(Manifest.permission.CAMERA) && Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
-            this.getBinding().buttonTakePicture.setVisibility(View.INVISIBLE);
-            this.subscribe(new SinglePermission(this, Manifest.permission.CAMERA),
-                    __ -> this.getBinding().buttonTakePicture.setVisibility(View.VISIBLE));
-        }
         this.getBinding().buttonTakePicture.setOnClickListener(v -> {
+            if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+                this.requestPermission(Manifest.permission.CAMERA);
+                return;
+            }
             try {
                 this.takePicture();
             } catch (IOException e) {
@@ -163,6 +159,17 @@ public class EditItemFragment extends FragmentBase<FragmentEditItemBinding> {
         this.getBinding().fab.setOnClickListener(__ -> this.saveItem());
     }
 
+    @Override
+    protected void onPermissionGranted(@NonNull String permission) {
+        if (permission.equals(Manifest.permission.CAMERA)) {
+            try {
+                this.takePicture();
+            } catch (IOException e) {
+                this.onActionError(e);
+            }
+        }
+    }
+
     /**
      * Saves the item to the server.
      */

app/src/main/java/rs/chir/invtracker/client/FragmentBase.java

@@ -5,6 +5,9 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
+import androidx.activity.result.ActivityResultCaller;
+import androidx.activity.result.ActivityResultLauncher;
+import androidx.activity.result.contract.ActivityResultContracts;
 import androidx.annotation.IdRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -19,6 +22,7 @@ import androidx.viewbinding.ViewBinding;
 
 import com.google.android.material.snackbar.Snackbar;
 
+import java.util.ConcurrentModificationException;
 import java.lang.reflect.InvocationTargetException;
 
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
@@ -280,4 +284,49 @@ public class FragmentBase<FragmentBinding extends ViewBinding> extends Fragment
     void navigate(NavDirections fragmentDirection) {
         this.getNavController().navigate(fragmentDirection);
     }
+
+    private String requestedPermission;
+
+    /**
+     * Permissions request launcher
+     */
+    private final ActivityResultLauncher<String> permissionLauncher = this.registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
+        var permission = this.requestedPermission;
+        this.requestedPermission = null;
+        if (isGranted) {
+            this.onPermissionGranted(permission);
+        } else {
+            this.onPermissionDenied(permission);
+        }
+    });
+
+    /**
+     * Called when the requested permission is granted
+     * @param permission the permission
+     */
+    protected void onPermissionGranted(@NonNull String permission) {
+    }
+    /**
+     * Called when the requested permission is denied
+     * @param permission the permission
+     */
+    protected void onPermissionDenied(@NonNull String permission) {
+      this.onActionError(new RuntimeException("Permission denied: " + permission));
+    }
+
+    /**
+     * Requests the given permission
+     * @param permission the permission to request
+     */
+    protected void requestPermission(@NonNull String permission) {
+        if(this.hasPermission(permission)) {
+            this.onPermissionGranted(permission);
+            return;
+        }
+        if(this.requestedPermission != null) {
+            throw new ConcurrentModificationException("Only one permission can be requested at a time");
+        }
+        this.requestedPermission = permission;
+        this.permissionLauncher.launch(permission);
+    }
 }

app/src/main/java/rs/chir/invtracker/client/MainActivity.java

@@ -8,6 +8,7 @@ import androidx.appcompat.app.AppCompatActivity;
 import androidx.navigation.Navigation;
 import androidx.navigation.ui.AppBarConfiguration;
 import androidx.navigation.ui.NavigationUI;
+import androidx.preference.PreferenceManager;
 
 import rs.chir.invtracker.client.databinding.ActivityMainBinding;
 
@@ -37,6 +38,9 @@ public class MainActivity extends AppCompatActivity {
 
         this.appBarConfiguration = new AppBarConfiguration.Builder(R.id.loadFragment, R.id.loginFragment, R.id.nearbyFragment).build();
         NavigationUI.setupActionBarWithNavController(this, navController, this.appBarConfiguration);
+
+        // Initialize settings
+        PreferenceManager.setDefaultValues(this, R.xml.root_preferences, false);
     }
 
     /**

app/src/main/java/rs/chir/invtracker/client/NearbyFragment.java

@@ -18,14 +18,13 @@ import rs.chir.invtracker.client.model.ItemListAdapter;
 import rs.chir.invtracker.model.GeoLocation;
 import rs.chir.invtracker.model.GeoRect;
 import rs.chir.invtracker.utils.SingleLocation;
-import rs.chir.invtracker.utils.SinglePermission;
 
 /**
  * Fragment that displays a list of items.
  */
 public class NearbyFragment extends FragmentBase<FragmentNearbyBinding> {
     /**
-     * The filter mode 
+     * The filter mode
      */
     private ListFilterMode filterMode = ListFilterMode.NEARBY;
 
@@ -33,19 +32,18 @@ public class NearbyFragment extends FragmentBase<FragmentNearbyBinding> {
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
 
-        // Check permissions
-        if (this.hasPermission(Manifest.permission.ACCESS_FINE_LOCATION)) {
-            this.fetchData();
-        } else {
-            // Request permission before fetching data
-            this.subscribe(new SinglePermission(this, Manifest.permission.ACCESS_FINE_LOCATION), __ -> this.fetchData());
-        }
+        this.requestPermission(Manifest.permission.ACCESS_FINE_LOCATION);
         // Initialize recyclerview
         this.getBinding().nearbyRecyclerView.setLayoutManager(new LinearLayoutManager(this.getContext()));
         this.getBinding().nearbyRecyclerView.addOnItemTouchListener(new NearbyOnTouchListener(this));
         this.getBinding().fab.setOnClickListener(__ -> this.navigate(R.id.action_nearbyFragment_to_QRScanFragment));
     }
 
+    @Override
+    protected void onPermissionGranted(@NonNull String permission) {
+        this.fetchData();
+    }
+
     @Nullable
     @Override
     protected MenuProvider getMenuProvider() {

app/src/main/java/rs/chir/invtracker/client/QRCodeFragment.java

@@ -22,7 +22,6 @@ import java.util.Map;
 
 import rs.chir.invtracker.client.databinding.FragmentQRCodeBinding;
 import rs.chir.invtracker.utils.BitmapStorage;
-import rs.chir.invtracker.utils.SinglePermission;
 
 /**
  * Fragment that displays a QR code for the item.
@@ -99,26 +98,16 @@ public class QRCodeFragment extends FragmentBase<FragmentQRCodeBinding> {
             this.onActionError(e);
         }
 
-        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
-            // pre android 10, we need external storage permission to save the QR code to the gallery
-            // so we ask for it here and disable the save button until we have it
-            this.getBinding().saveToGalleryButton.setEnabled(false);
-            this.subscribe(new SinglePermission(this.requireActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE),
-                    __ -> this.getBinding().saveToGalleryButton.setEnabled(true),
-                    __ -> this.getBinding().saveToGalleryButton.setEnabled(false)); // may be extraneous
-        }
-
         this.getBinding().imageView.setImageBitmap(this.bitmap);
         this.getBinding().imageView.setContentDescription("https://invtracker.chir.rs/objects/" + mId);
 
         this.getBinding().saveToGalleryButton.setOnClickListener(__ -> {
-            try {
-                // save the QR code to the gallery
-                BitmapStorage.create(this.requireContext()).storeBitmap(this.bitmap, "qr_code_" + mId);
-            } catch (IOException e) {
-                this.onActionError(e);
+            // pre android 10, we need external storage permission to save the QR code to the gallery
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
+                this.requestPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE);
+            } else {
+                this.storeBitmap();
             }
-            this.getNavController().navigateUp(); // we are done here
         });
 
         this.getBinding().print.setOnClickListener(__ -> {
@@ -128,4 +117,19 @@ public class QRCodeFragment extends FragmentBase<FragmentQRCodeBinding> {
             this.getNavController().navigateUp();
         });
     }
+
+    private void storeBitmap() {
+        try {
+            // save the QR code to the gallery
+            BitmapStorage.create(this.requireContext()).storeBitmap(this.bitmap, "qr_code_" + mId);
+        } catch (IOException e) {
+            this.onActionError(e);
+        }
+        this.getNavController().navigateUp(); // we are done here
+    }
+
+    @Override
+    protected void onPermissionGranted(@NonNull String permission) {
+      this.storeBitmap();
+    }
 }

app/src/main/java/rs/chir/invtracker/client/QRScanFragment.java

@@ -31,7 +31,6 @@ import rs.chir.invtracker.client.databinding.FragmentQrScanBinding;
 import rs.chir.invtracker.model.GeoLocation;
 import rs.chir.invtracker.utils.ListenableFutureAdapter;
 import rs.chir.invtracker.utils.SingleLocation;
-import rs.chir.invtracker.utils.SinglePermission;
 import rs.chir.utils.math.Vec2;
 
 /**
@@ -52,6 +51,8 @@ public class QRScanFragment extends FragmentBase<FragmentQrScanBinding> implemen
      */
     private boolean hasPaused = false;
 
+    private long id;
+
     /**
      * Initializes the cosmetic alignment box
      */
@@ -71,7 +72,7 @@ public class QRScanFragment extends FragmentBase<FragmentQrScanBinding> implemen
         this.initViewfinderBox();
 
         // Make sure we have the needed permissions
-        this.subscribe(new SinglePermission(this, Manifest.permission.CAMERA), __ -> this.startCamera());
+        this.requestPermission(Manifest.permission.CAMERA);
     }
 
     @Override
@@ -81,6 +82,28 @@ public class QRScanFragment extends FragmentBase<FragmentQrScanBinding> implemen
         this.getNavController().popBackStack();
     }
 
+    @Override
+    protected void onPermissionGranted(String permission) {
+      if(permission.equals(Manifest.permission.CAMERA)) {
+          this.startCamera();
+      } else if (permission.equals(Manifest.permission.ACCESS_FINE_LOCATION)) {
+          var fusedLocationClient = LocationServices.getFusedLocationProviderClient(this.requireActivity());
+          this.subscribe(SingleLocation.getNextLocation(fusedLocationClient, this.requireContext()), location -> this.updateLocation(id, location), err -> {
+              err.printStackTrace();
+              this.showDetailView(id);
+          });
+      }
+    }
+
+    @Override
+    protected void onPermissionDenied(String permission) {
+        if(permission.equals(Manifest.permission.ACCESS_FINE_LOCATION)) {
+            this.showDetailView(id);
+        } else {
+            super.onPermissionDenied(permission);
+        }
+    }
+
     @Override
     public void onPause() {
         super.onPause();
@@ -131,17 +154,8 @@ public class QRScanFragment extends FragmentBase<FragmentQrScanBinding> implemen
                 return; // should not happen
             // while we are determining the location, we don’t want to show the user the viewfinder
             this.hideUI(true);
-            var id = Long.parseLong(group);
-            // TODO: request location permission
-            if (this.hasPermission(Manifest.permission.ACCESS_FINE_LOCATION)) {
-                var fusedLocationClient = LocationServices.getFusedLocationProviderClient(this.requireActivity());
-                this.subscribe(SingleLocation.getNextLocation(fusedLocationClient, this.requireContext()), location -> this.updateLocation(id, location), err -> {
-                    err.printStackTrace();
-                    this.showDetailView(id);
-                });
-            } else {
-                this.showDetailView(id);
-            }
+            this.id = Long.parseLong(group);
+            this.requestPermission(Manifest.permission.ACCESS_FINE_LOCATION);
         } else {
             Snackbar.make(this.getBinding().getRoot(), "Invalid QR code", BaseTransientBottomBar.LENGTH_LONG).show();
             this.hasScanned.set(false);

app/src/main/java/rs/chir/invtracker/utils/SinglePermission.java

@@ -1,63 +0,0 @@
-package rs.chir.invtracker.utils;
-
-import android.util.AndroidException;
-
-import androidx.activity.result.ActivityResultCaller;
-import androidx.activity.result.ActivityResultLauncher;
-import androidx.activity.result.contract.ActivityResultContracts;
-import androidx.annotation.NonNull;
-
-import java.util.List;
-
-import io.reactivex.rxjava3.core.Single;
-import io.reactivex.rxjava3.core.SingleObserver;
-
-/**
- * {@link Single} that completes when the user grants the requested permissions and errors otherwise.
- */
-public class SinglePermission extends Single<String> {
-    /** 
-     * The subscribers to this {@link Single}.
-     */
-    private final List<SingleObserver<? super String>> subscribers = new java.util.ArrayList<>(1);
-    /**
-     * Permission that is requested.
-     */
-    private final String permission;
-    /**
-     * The {@link ActivityResultLauncher} for requesting the permission.
-     */
-    private final ActivityResultLauncher<String> launcher;
-
-    /**
-     * Creates a new {@link SinglePermission} for the given permission.
-     *
-     * <br>
-     * This function needs to be called before the {@link android.app.Activity} or {@link android.app.Fragment} is started.
-     *
-     * @param activity An activity or fragment.
-     * @param permission The permission to request.
-     */
-    public SinglePermission(@NonNull ActivityResultCaller activity, String permission) {
-        this.launcher = activity.registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
-            if (isGranted) {
-                for (var subscriber : subscribers) {
-                    subscriber.onSuccess(permission);
-                }
-            } else {
-                for (var subscriber : subscribers) {
-                    subscriber.onError(new AndroidException("Permission denied"));
-                }
-            }
-        });
-        this.permission = permission;
-    }
-
-    @Override
-    protected void subscribeActual(@io.reactivex.rxjava3.annotations.NonNull SingleObserver<? super String> observer) {
-        subscribers.add(observer);
-        if (subscribers.size() == 1) {
-            launcher.launch(permission);
-        }
-    }
-}

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

@@ -84,4 +84,4 @@
     <string name="qr_scan_fragment_label">QR Code Scanner</string>
     <string name="qr_code_fragment">QR Code</string>
     <string name="edit_item_fragment">Edit Item</string>
-</resources>
+</resources>

app/src/main/res/xml/root_preferences.xml

@@ -4,7 +4,7 @@
 
         <ListPreference
             android:id="@+id/pref_location_privacy"
-            android:defaultValue="location_round"
+            android:defaultValue="privacy_round"
             android:entries="@array/demo_privacy_type_lbl"
             android:entryValues="@array/demo_privacy_type"
             android:key="location_privacy"
@@ -18,4 +18,4 @@
             android:title="@string/preference_location_accuracy"
             app:min="0" />
     </PreferenceCategory>
-</PreferenceScreen>
+</PreferenceScreen>