Develop code that implements lazy loading images

1. The front-end performance optimization of key programs, through pictures or delay in loading the data, we can speed up page rendering speed, so for the first time opens the page faster, only to slide to an area, it loads the real picture, which also save load flow,

2. The processing solutions, all the lazy FIG valves with a wrapped box, and the default width and height provided placeholder FIG. Src started to make all IMg is empty, the real address on the custom properties IMG, allowing IMG hide, wait until after all other resources are loaded, we then begin loading map valves, valves for a variety of plots, as needed after the page scroll when the current map loaded valves fully displayed the true picture Aberdeen