android 文件下载及进度条显示

android 文件下载

进度条：

ProgressDialog progress = new ProgressDialog(context);

progress.setTitle(“文件下载”);

progress.setMessage("loading...");

progress.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);

progress.setIndeterminate(false);//设置为fase等待进度更新，设置为true则左右循环滚动

progress.setMax(100);

下载部分

HttpURLConnection conn = null;

URL url = null;

url = new URL(connStr);//connStr，访问路径

conn = url.openConnection();

long size = conn.getContentLength();//文件大小

BufferedInputStream in = new BufferedInputStream(conn.openStream());

ByteArrayOutputStream dataStream = new ByteArrayOutputStream();

BufferedOutputStream out = new BufferedOutputStream(dataStream);

int count = 0;

long total = 0L;

byte[] data = new byte[512];

while((count = in.read(data)) != -1){

　　total += count;

　　publishProgress((int)(total*100/size));//放在Asycntask里面做进度条更新;

　　out.write(data,0,count);

}

out.flush();

byte[] bytes = dataStream.toByteArray();

String s = new String(bytes);//转换成对应的类型

return s;