默认动态样式对象。 
它由一个callback或判別式和被适用于通过判別式的时点的样式列表所构成。
    grid.setColumns([{
        name: "category",
        fieldName: "category",
        width: 100,
        styles: { textAlignment: "far" },
        dynamicStyles: [{
            expression: "value not ilike '%Damage%'",
            styles: {
                "background": "#1100ff00"
            }
        }],
        header: { text: "Category" }
    },
    ...
    ]);
    grid.setColumns([{
        name: "category",
        fieldName: "category",
        width: 100,
        styles: { textAlignment: "far" },
        dynamicStyles: [{
            callback: function (scope) {
                return !scope.value() || !scope.value().match(/Damag/i);
            },
            styles: {
                "background": "#1100ff00"
            }
        }],
        header: { text: "Category" }
    },
    ...
    ]);