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function ObjectCellRenderer() {
}

ObjectCellRenderer.prototype.init = function (params) {
    this.span = document.createElement('span');
    this.span.title=''
    this.span.innerHTML='';
    this.refresh(params)
};

ObjectCellRenderer.prototype.refresh = function(params) {
    var res = ''
    if(params.value) {
        for(var i=0;i<params.fields.length;i++) {
            res += params.fields[i].label + ': ';
            res+=params.value[params.fields[i].name] + ' ';
        }
    }
    
    this.span.innerHTML=res;
}

ObjectCellRenderer.prototype.getGui = function () {
    return this.span;
};


function ObjectEditor() {
    
}

var onKeyDown = function(event) {
        var key = event.which || event.keyCode;
        if (key == 37 ||  // left
            key == 39 || // right
            key == 9 ) {  // tab
            event.stopPropagation();
        }
    }

ObjectEditor.prototype.init = function (params) {
    this.container = document.createElement('div');
    this.container.style = "border-radius: 15px; border: 1px solid grey;background: #e6e6e6;padding: 10px; ";
    this.container.onkeydown = onKeyDown
    
    for(i=0;i<params.fields.length;i++) {
        var field = params.fields[i];
        var label = document.createElement('label');
				label.innerHTML = field.label+': ';
        var input = document.createElement('input');
        input.name = field.name;
        if (params.value) {
        	input.value = params.value[field.name]; 
        }
        
        this.container.appendChild(label);
        this.container.appendChild(input);
        this.container.appendChild(document.createElement('br'));
    }
    
    var saveButton = document.createElement('button');
    saveButton.appendChild(document.createTextNode('Ok'))
    saveButton.addEventListener('click', function (event) {
        params.stopEditing();
    });
    this.container.appendChild(saveButton);
};

ObjectEditor.prototype.getGui = function () {
    return this.container;
};

ObjectEditor.prototype.afterGuiAttached = function () {
    var inputs = this.container.getElementsByTagName('input');
    inputs[0].focus();    
};

ObjectEditor.prototype.getValue = function () {
    var res = {};
    var inputs = this.container.getElementsByTagName('input');
    for(j=0;j<inputs.length;j++) {
          res[inputs[j].name] = inputs[j].value.replace(/^\s+|\s+$/g, "");
    }
    return res;
};

ObjectEditor.prototype.destroy = function () {
};

ObjectEditor.prototype.isPopup = function () {
    return true;
};

var addressFields = [
	{'name': 'address', 'label': 'Address' },
  {'name': 'zip', 'label': 'ZIP' },
  {'name': 'city', 'label': 'City' },
]

var columns = [
    {
        headerName: 'ID', field: 'id', width: 50, editable: true  
    }, {
        headerName: 'Name', field: 'name', width: 100, editable: true
    }, {
        headerName: "Address", field: "address", width: 200, editable: true,
        cellRenderer: ObjectCellRenderer,
        cellEditor: ObjectEditor,
        cellEditorParams: {
          fields: addressFields
        },
        cellRendererParams: {
          fields: addressFields
        }
    }, {
        headerName: "Children", field: "children", width: 200, editable: true
    }
];

var gridOptions = {
    columnDefs: columns,
    rowData: []
};

new agGrid.Grid(document.querySelector('#myGrid'), gridOptions);

document.querySelector('#addRow').addEventListener("click", function() {
    gridOptions.api.addItems([{}]);
});

<button id='addRow' >Add row</button>
<div id="myGrid" style="height: 500px" class="ag-blue"></div>