MLDB: asyncronous variant of getOption

diff --git a/app/src/main/java/net/ktnx/mobileledger/utils/GetOptCallback.java b/app/src/main/java/net/ktnx/mobileledger/utils/GetOptCallback.java
new file mode 100644 (file)
index 0000000..c30c150
--- /dev/null
+++ b/app/src/main/java/net/ktnx/mobileledger/utils/GetOptCallback.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright © 2019 Damyan Ivanov.
+ * This file is part of MoLe.
+ * MoLe is free software: you can distribute it and/or modify it
+ * under the term of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your opinion), any later version.
+ *
+ * MoLe is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License terms for details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with MoLe. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package net.ktnx.mobileledger.utils;
+
+abstract public class GetOptCallback {
+    protected abstract void onResult(String result);
+}

diff --git a/app/src/main/java/net/ktnx/mobileledger/utils/MLDB.java b/app/src/main/java/net/ktnx/mobileledger/utils/MLDB.java
index a735ee9022b2fa91695d4fcc465ff747d5935c92..832d57d759da8ea2b6457170ceec7392d9682fc1 100644 (file)
--- a/app/src/main/java/net/ktnx/mobileledger/utils/MLDB.java
+++ b/app/src/main/java/net/ktnx/mobileledger/utils/MLDB.java
@@ -26,6 +26,7 @@ import android.database.MatrixCursor;
 import android.database.SQLException;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteOpenHelper;
+import android.os.AsyncTask;
 import android.os.Build;
 import android.provider.FontsContract;
 import android.util.Log;
@@ -94,6 +95,38 @@ public final class MLDB {
             return default_value;
         }
     }
+    static public void getOption(String name, String defaultValue, GetOptCallback cb) {
+        AsyncTask<Void, Void, String> t = new AsyncTask<Void, Void, String>() {
+            @Override
+            protected String doInBackground(Void... params) {
+                SQLiteDatabase db = getDatabase();
+                try (Cursor cursor = db
+                        .rawQuery("select value from options where profile = ? and name=?",
+                                new String[]{NO_PROFILE, name}))
+                {
+                    if (cursor.moveToFirst()) {
+                        String result = cursor.getString(0);
+
+                        if (result == null) result = defaultValue;
+
+                        debug("async-db", "option " + name + "=" + result);
+                        return result;
+                    }
+                    else return defaultValue;
+                }
+                catch (Exception e) {
+                    debug("db", "returning default value for " + name, e);
+                    return defaultValue;
+                }
+            }
+            @Override
+            protected void onPostExecute(String result) {
+                cb.onResult(result);
+            }
+        };
+
+        t.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, (Void) null);
+    }
     static public String getOption(String name, String default_value) {
         debug("db", "about to fetch option " + name);
         SQLiteDatabase db = getDatabase();