3
I’m using the plugin JS Webix to create grid dynamic. 
It has a functionality to export to PDF/Excel, on the site has the following example:
grid = new webix.ui({
    view:"datatable",
    columns:[...],
    "export":true
});
and to trigger, the button:
<input type="button" value="Get as PDF" style='width:400px;margin:25px;' onclick="grid.exportToPDF();">
Where grid is the instance of webix.ui that contain the datatable
How do I export if a datatable is inside a layout?
Example: 
new webix.ui({
    type:"line", id:"a1", rows:[
        {type:"head", padding:0, responsive:"a1", cols:[
                {template:"<?=$rel->getHeader_logo()?>", css:"cabecalho-webix", height:84, minWidth:200},
                {template:"<?=$rel->getHeader_titulo()?>", css:"cabecalho-webix", height:84, minWidth:300},
                {template:"<?=$rel->getHeader_dataemissao()?>", css:"cabecalho-webix", height:84, minWidth:200}
        ]},
        {type:"line", padding:0, responsive:"a1", cols:[
            {
                container:"testA",
                view:"datatable",
                columns: <?= $json; ?>,
                footer:false,
                autoheight:false,
                data:<?= $json_body; ?>,
                scrollAlignY:true,
                export:true,
                resizeColumn:true,
                resizeRow:false,
                dragColumn:true
            }
        ]},
        {type:"line", padding:0, responsive:"a1", cols:[
            {template:"<span id='imprimir' onclick='printGrid();'><img src='images/bt_imprimir.png'></span>", height:60}
        ]}
    ]
}).show();
Thanks, that took care.
– Malgany