实现自定义的UISlider,可以实时显示slider值，文本可以随thumb的滑动同步滑动-The UISlider custom, real-time display slider value, the text can be synchronized with the thumb sliding sliding

一个天气预报的ios软件，能实时显示中国各个城市的天气预报(A weather forecast IOS software that can show the weather forecast in every city in China in real time)