SMART datagrid v.1 > Classes > ButtonCellRenderer
被显示在disabled状态的按钮的文本。 
如果指定null或undefined,就会显示指定在text的值。 
如果指定""(空字符串),就不会显示文本。v 1.3.8
默认值为undefined.
    var columns = [{
        name: "column1",
        renderer: {
            type: "button",
            disabledText : "Not Avaliable"
        }
    },
    ...
    ];
    grid.setColumns(columns);
    $("#changeText").click(function () {
        var col = grid.columnByName('column1');
        col.setRenderer({ 
            disabledText : "Not Avaliable"
        });
    });