Dynamic array in Solidity

Solution 1:

Here is my solution, you need experimental ABIEncoderV2 to return array of strings.

pragma solidity ^0.5.2;
pragma experimental ABIEncoderV2;

contract Test {

    string[] array;

    function push(string calldata _text) external {
        array.push(_text);
    }

    function get() external view returns(string[] memory) {
        return array;
    }
}

Solution 2:

If, finally, you want to interact with your smart contract with tools like web3j (for java) or web3js (javascript) in an application, working with dynamic arrays is not going to work because of some bugs in those libraries.
In this case you should serialize your output array. Same applies if you have an input array.