var grid = new tui.Grid({
    el: $('#grid'),
    data: gridData,
    rowHeaders: ['rowNum', 'radio'],
    bodyHeight: 300,
    rowHeight: 40,
    virtualScrolling: true,
    treeColumnOptions: {
        name: 'name',
        useCascadingCheckbox: false
    },
    columns: [
        {
            title: 'Name',
            name: 'name',
            width: 300,
            editOptions: {
                type: 'text',
                useViewMode: true
            }
        },
        {
            title: 'Artist',
            name: 'artist'
        },
        {
            title: 'Type',
            name: 'type'
        },
        {
            title: 'Release',
            name: 'release'
        },
        {
            title: 'Genre',
            name: 'genre'
        }
    ]
});

function appendRows(parentRowKey, isDynamicLoaing) {
    var childrenRowData = [
        {
            id: 502796,
            name: 'test4',
            artist: 'test4',
            release: '2015.05.12',
            type: 'EP',
            typeCode: '2',
            genre: 'Hiphop',
            genreCode: '5',
            grade: '5',
            price: 18000,
            downloadCount: 1000,
            listenCount: 5000
        },
        {
            id: 502790,
            name: 'test5',
            artist: 'test5',
            release: '2015.05.12',
            type: 'EP',
            typeCode: '2',
            genre: 'Hiphop',
            genreCode: '5',
            grade: '5',
            price: 18000,
            downloadCount: 1000,
            listenCount: 5000
        }
    ];

    grid.appendRow([{
        id: 502795,
        name: 'test1',
        artist: 'test1',
        release: '2015.05.12',
        type: 'EP',
        typeCode: '2',
        genre: 'Hiphop',
        genreCode: '5',
        grade: '5',
        price: 18000,
        downloadCount: 1000,
        listenCount: 5000,
        _extraData: {
            treeState: 'COLLAPSE'
        },
        _children: isDynamicLoaing ? true : childrenRowData
    },
    {
        id: 502793,
        name: 'test2',
        artist: 'test2',
        release: '2015.05.12',
        type: 'EP',
        typeCode: '2',
        genre: 'Hiphop',
        genreCode: '5',
        grade: '5',
        price: 18000,
        downloadCount: 1000,
        listenCount: 5000
    },
    {
        id: 502797,
        name: 'test3',
        artist: 'test3',
        release: '2015.05.12',
        type: 'EP',
        typeCode: '2',
        genre: 'Hiphop',
        genreCode: '5',
        grade: '5',
        price: 18000,
        downloadCount: 1000,
        listenCount: 5000
    }], {
        parentRowKey: parentRowKey
    });
}

function removeRows(rowKeys) {
    _.each(rowKeys, function(rowKey) {
        grid.removeRow(rowKey);
    });
}

$('#append').on('click', function() {
    var parentRowKey = grid.getCheckedRowKeys()[0];

    appendRows(parentRowKey);
});

$('#remove').on('click', function() {
    var rowKeys = grid.getCheckedRowKeys();

    removeRows(rowKeys);
});

grid.on('expanded', function(ev) {
    var parentRowKey = ev.rowKey;
    var descendantRowKeys = ev.descendantRowKeys;

    if (!descendantRowKeys.length) {
        removeRows(descendantRowKeys);
        appendRows(parentRowKey, true);
    }
});

<div id="grid"></div>