callback test

doric/template/custom_callback.h

@@ -0,0 +1,23 @@
+#ifndef CUSTOM_CALLBACK_H
+#define CUSTOM_CALLBACK_H
+
+#include "async/callback.h"
+
+template <class R>
+class CustomCallback : public Callback<R> {
+
+public:
+    void onResult(R result) override {
+
+    }
+
+    void onError(QException exception) override {
+
+    }
+
+    void onFinish() override {
+
+    }
+};
+
+#endif // CUSTOM_CALLBACK_H