Use QML WorkerScript for loading and updating models

common/ModelWorkerScript.qml

@@ -0,0 +1,67 @@
+
+/**
+ *
+ * gPodder QML UI Reference Implementation
+ * Copyright (c) 2015, Thomas Perl <m@thp.io>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+import QtQuick 2.0
+
+
+WorkerScript {
+    source: 'modelworker.js'
+
+    property int callbacks_seq: 1
+    property var callbacks: ({})
+
+    function refCallback(callback) {
+        var id = callbacks_seq++;
+        callbacks[id] = callback;
+        return id;
+    }
+
+    function unrefCallback(callback) {
+        var result = callbacks[callback];
+        delete callbacks[callback];
+        return result;
+    }
+
+    function updateModelFrom(model, data, callback) {
+        sendMessage({
+            action: 'updateModelFrom',
+            model: model,
+            data: data,
+            callback: refCallback(callback),
+        });
+    }
+
+    function updateModelWith(model, key, value, update, callback) {
+        sendMessage({
+            action: 'updateModelWith',
+            model: model,
+            key: key,
+            value: value,
+            update: update,
+            callback: refCallback(callback),
+        });
+    }
+
+    onMessage: {
+        if (messageObject.callback !== undefined) {
+            unrefCallback(messageObject.callback)();
+        }
+    }
+}