Can't create handler inside thread that has not called Looper.prepare()

FATAL EXCEPTION: OkHttp Dispatcher

Can't create handler inside thread that has not called Looper.prepare()

产生异常的原因：只是想写个Toast.makeText(MainActivity.this,"连接成功！",Toast.LENGTH_SHORT).show();来提示连接服务器成功或者失败，为什么会出错。实际需要调用线程来启动Toast，不能直接调用。

解决方法：调用线程来处理

runOnUiThread(new Runnable() {
　　@Override
　　public void run() {
　　Toast.makeText(MainActivity.this,"连接成功！",Toast.LENGTH_SHORT).show();
　　}
});