8     layout::grid::{Grid, GridArrangeType},
27     let grid = Grid::new();  in main()  localVariable
28     grid.set_arrange_type(GridArrangeType::Horizontal); //优先横向排列  in main()
29     grid.set_upper_limit(3); //每行最大元素个数为3  in main()
31     grid.set_space(20, 20);  in main()
32     grid.add_element(&image1);  in main()
33     grid.add_element(&image2);  in main()
34     grid.add_element(&image3);  in main()
35     grid.add_element(&image4);  in main()
36     grid.add_element(&image5);  in main()
38     panel.add_child(&grid);  in main()