// assumes you have a variables called `my_data` which is an array of arrays of numbers
auto table = new TableView(window);
// snip: you would set up columns here

// this is how you provide data to the table view class
table.getData = delegate(int row, int column, scope void delegate(in char[]) sink) {
	import std.conv;
	sink(to!string(my_data[row][column]));
};

// and this is how you customize the colors
table.getCellStyle = delegate(int row, int column) {
	return (my_data[row][column] < 0) ?
		TableView.CellStyle(Color.red); // make negative numbers red
		: TableView.CellStyle.init; // leave the rest alone
};
// snip: you would call table.setItemCount here then continue with the rest of your window setup work