Make the Android geocoder an observable

Part of #4522.

3 files changed, 72 insertions, 82 deletions

diff --git a/main/src/cgeo/geocaching/AddressListActivity.java b/main/src/cgeo/geocaching/AddressListActivity.java
index 4f71ab6..f51d37c 100644
--- a/main/src/cgeo/geocaching/AddressListActivity.java
+++ b/main/src/cgeo/geocaching/AddressListActivity.java
@@ -1,14 +1,14 @@
 package cgeo.geocaching;
 
 import cgeo.geocaching.activity.AbstractListActivity;
-import cgeo.geocaching.location.Geocoder;
+import cgeo.geocaching.location.AndroidGeocoder;
 import cgeo.geocaching.ui.AddressListAdapter;
 
-import org.apache.commons.collections4.CollectionUtils;
+import rx.android.observables.AndroidObservable;
+import rx.functions.Action1;
 
 import android.app.ProgressDialog;
 import android.location.Address;
-import android.os.AsyncTask;
 import android.os.Bundle;
 
 import java.util.List;
@@ -39,27 +39,21 @@ public class AddressListActivity extends AbstractListActivity {
     }
 
     private void lookupAddressInBackground(final String keyword, final AddressListAdapter adapter, final ProgressDialog waitDialog) {
-        new AsyncTask<Void, Void, List<Address>>() {
-
-            @Override
-            protected List<Address> doInBackground(final Void... params) {
-                final Geocoder geocoder = new Geocoder(AddressListActivity.this);
-                return geocoder.getFromLocationName(keyword);
-            }
-
+        final AndroidGeocoder geocoder = new AndroidGeocoder(this);
+        AndroidObservable.bindActivity(this, geocoder.getFromLocationName(keyword).toList()).subscribe(new Action1<List<Address>>() {
             @Override
-            protected void onPostExecute(final List<Address> addresses) {
+            public void call(final List<Address> addresses) {
                 waitDialog.dismiss();
-                if (CollectionUtils.isNotEmpty(addresses)) {
-                    for (final Address address : addresses) {
-                        adapter.add(address); // don't use addAll, it's only available with API >= 11
-                    }
-                } else {
-                    finish();
-                    CacheListActivity.startActivityAddress(AddressListActivity.this, null, keyword);
+                for (final Address address : addresses) {
+                    adapter.add(address); // don't use addAll, it's only available with API >= 11
                 }
             }
-
-        }.execute();
+        }, new Action1<Throwable>() {
+            @Override
+            public void call(final Throwable throwable) {
+                finish();
+                CacheListActivity.startActivityAddress(AddressListActivity.this, null, keyword);
+            }
+        });
     }
 }
\ No newline at end of file
diff --git a/main/src/cgeo/geocaching/location/AndroidGeocoder.java b/main/src/cgeo/geocaching/location/AndroidGeocoder.java
new file mode 100644
index 0000000..373e40e
--- /dev/null
+++ b/main/src/cgeo/geocaching/location/AndroidGeocoder.java
@@ -0,0 +1,57 @@
+package cgeo.geocaching.location;
+
+import cgeo.geocaching.utils.Log;
+import cgeo.geocaching.utils.RxUtils;
+
+import org.apache.commons.collections4.CollectionUtils;
+import org.eclipse.jdt.annotation.NonNull;
+
+import rx.Observable;
+import rx.functions.Func0;
+
+import android.content.Context;
+import android.location.Address;
+import android.location.Geocoder;
+
+import java.util.List;
+import java.util.Locale;
+
+/**
+ * Encapsulation of the Android {@link Geocoder} with default error handling. All methods of this class
+ * are blocking and will do network lookups.
+ *
+ */
+public class AndroidGeocoder {
+    private final Geocoder geocoder;
+
+    public AndroidGeocoder(final Context context) {
+        geocoder = new Geocoder(context, Locale.getDefault());
+    }
+
+    /**
+     * Retrieve addresses from a textual location using Android geocoding API. The works happens on the network scheduler.
+     *
+     * @param keyword the location
+     * @return an observable containing zero or more locations
+     *
+     * @see Geocoder#getFromLocationName(String, int)
+     */
+    public Observable<Address> getFromLocationName(@NonNull final String keyword) {
+        return Observable.defer(new Func0<Observable<Address>>() {
+            @Override
+            public Observable<Address> call() {
+                try {
+                    final List<Address> addresses = geocoder.getFromLocationName(keyword, 20);
+                    if (CollectionUtils.isEmpty(addresses)) {
+                        return Observable.error(new RuntimeException("no result from Android geocoder"));
+                    }
+                    return Observable.from(addresses);
+                } catch (final Exception e) {
+                    Log.i("Unable to use Android geocoder: " + e.getMessage());
+                    return Observable.error(e);
+                }
+            }
+        }).subscribeOn(RxUtils.networkScheduler);
+    }
+
+}
diff --git a/main/src/cgeo/geocaching/location/Geocoder.java b/main/src/cgeo/geocaching/location/Geocoder.java
deleted file mode 100644
index 1582daa..0000000
--- a/main/src/cgeo/geocaching/location/Geocoder.java
+++ /dev/null
@@ -1,61 +0,0 @@
-package cgeo.geocaching.location;
-
-import cgeo.geocaching.utils.Log;
-
-import org.apache.commons.lang3.StringUtils;
-import org.eclipse.jdt.annotation.NonNull;
-
-import android.content.Context;
-import android.location.Address;
-
-import java.io.IOException;
-import java.util.Collections;
-import java.util.List;
-import java.util.Locale;
-
-/**
- * Encapsulation of the Android {@link android.location.Geocoder} with default error handling. All methods of this class
- * are blocking and will do network lookups.
- *
- */
-public class Geocoder {
-    private final android.location.Geocoder geocoder;
-
-    public Geocoder(final Context context) {
-        geocoder = new android.location.Geocoder(context, Locale.getDefault());
-    }
-
-    /**
-     * @param keyword
-     * @return
-     *
-     * @see android.location.Geocoder#getFromLocationName(String, int)
-     */
-    public @NonNull List<Address> getFromLocationName(final String keyword) {
-        try {
-            return geocoder.getFromLocationName(keyword, 20);
-        } catch (final Exception e) {
-            handleException(e);
-            return Collections.emptyList();
-        }
-    }
-
-    public @NonNull List<Address> getFromLocation(final Geopoint coords) {
-        try {
-            return geocoder.getFromLocation(coords.getLatitude(), coords.getLongitude(), 20);
-        } catch (final IOException e) {
-            handleException(e);
-            return Collections.emptyList();
-        }
-    }
-
-    private static void handleException(final Exception e) {
-        // non Google devices come without the geocoder
-        if (StringUtils.containsIgnoreCase(e.getMessage(), "Service not Available")) {
-            Log.i("No geocoder available");
-        }
-        else {
-            Log.e("Geocoder", e);
-        }
-    }
-}