The snippet below is from this sample
watchUtils.whenTrue(view, "stationary", function() {
if (view.center) {
var info =
"<br> <span> the view center changed. </span> x: " +
view.center.x.toFixed(2) +
" y: " +
view.center.y.toFixed(2);
displayMessage(info);
}
if (view.extent) {
var info =
"<br> <span> the view extent changed: </span>" +
"<br> xmin:" +
view.extent.xmin.toFixed(2) +
" xmax: " +
view.extent.xmax.toFixed(2) +
"<br> ymin:" +
view.extent.ymin.toFixed(2) +
" ymax: " +
view.extent.ymax.toFixed(2);
displayMessage(info);
}
});