Cannot submit a transcation in composer playground? - hyperledger

Question

Problem:
I have created and deployed a business network in https://composer-playground.mybluemix.net. There I can create participant and assets as I expected. But Submit Transaction button is disable.
This is my .cto file.Where I wrote business network model.
namespace org.landreg
abstract concept Address {
o String addressLine
o String locality
}
concept DutchAddress {
o String postalCode regex=/\d{4}[ ]??[A-Z]{2}/
}
enum Gender {
o FEMALE
o MALE
}
participant Individual identified by passportNumber{
o String passportNumber
o DutchAddress address
o Gender gender
}
asset LandTitle identified by id {
o String id
o DutchAddress address
o Integer area range=[1000,]
o Boolean forSale default=false
o Double price optional
--> Individual owner
--> Individual[] previousOwners
}
abstract transaction UnlockLandTitle {
-->LandTitle landTitle
}
This is my logic.js file.Where I define the transaction.
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
"use strict";
/**
* Write your transction processor functions here
*/
const NS = "org.landreg";
/**
* Sample transaction
* #param {org.landreg.UnlockLandTitle} tx //transaction object define in the cto file
* #transaction
*/
async function UnlockLandTitle(tx) {
//Get asset registery for landTitles
const landTitleRegistry = await getAssetRegistry(NS + ".LandTitle");
if (tx.landTitle.forSale) {
throw new Error(
`Land Title with id ${tx.landTitle.getIdentifier()} is already unlocked for sale`
);
}
// Unlock asset to be for sale
tx.landTitle.forSale = true;
await landTitleRegistry.update(tx.landTitle);
}
Can someone help me to solve this problem? Because without solving this I cannot go forward.I search and try to solve this problem.But I was unable to find any solution for this problem.Thank You!

Answer 1

The problem is in your Model(.cto) file.
You can not use abstract with transaction, just remove abstract keyword.
transaction UnlockLandTitle {
--> LandTitle landTitle
}