因为这里存在线程安全问题，把我发的android developer文档的连接看完，你会了解google的一些设计理念Threads ... Additionally, the Andoid UI toolkit is not thread-safe. So, you must not manipulate your UI from a worker thread—you must do all manipulation to your user interface from the UI thread. Thus, there are simply two rules to Android's single thread model:1. Do not block the UI thread 2. Do not access the Android UI toolkit from outside the UI thread
直接通过一个thread来操作UI控件不报错只是运气建议买本Android开发相关的书籍，比如Pro Android 4
或者多看看android developer网址的guide及training
http://developer.android.com/guide/components/processes-and-threads.html
...
Additionally, the Andoid UI toolkit is not thread-safe. So, you must not manipulate your UI from a worker thread—you must do all manipulation to your user interface from the UI thread. Thus, there are simply two rules to Android's single thread model:1. Do not block the UI thread
2. Do not access the Android UI toolkit from outside the UI thread
http://blog.csdn.net/zhaokaiqiang1992/article/details/43410351