private ProgressDialog mDialog;

progressDialog = new ProgressDialog( ProgressDialogActivity.this); 
      //设置进度条风格，风格为圆形，旋转的 
      progressDialog.setProgressStyle( 
        ProgressDialog.STYLE_SPINNER); 
      //设置ProgressDialog 标题 
      progressDialog.setTitle("下载"); 
      //设置ProgressDialog 提示信息 
      progressDialog.setMessage("这是一个圆形进度条对话框"); 
      //设置ProgressDialog 标题图标 
      progressDialog.setIcon(Android.R.drawable.btn_star); 
      //设置ProgressDialog 的进度条是否不明确 
      progressDialog.setIndeterminate(false); 
      //设置ProgressDialog 是否可以按退回按键取消 
      progressDialog.setCancelable(true); 
      // 让ProgressDialog显示 
      progressDialog.show(); 

progressDialog.dismiss();