Android线程交互（Handler+Thread 和 AsyncTask）

核心提示：byte[] buf = new byte[128];int ch = -1;int count = 0;while ((ch = is.read(buf)) != -1) {baos.write(buf, 0, ch);count += ch;if (length > 0) {// 如果知道响应的长度，调用pu

byte[] buf = new byte[128];

int ch = -1;

int count = 0;

while ((ch = is.read(buf)) != -1) {

baos.write(buf, 0, ch);

count += ch;

if (length > 0) {

// 如果知道响应的长度，调用publishProgress()更新进度

publishProgress((int) ((count / (float) length) * 100));

}

// 为了在模拟器中清楚地看到进度，让线程休眠100ms

Thread.sleep(100);

}

s = new String(baos.toByteArray()); }

// 返回结果

return s;

} catch (Exception e) {

e.printStackTrace();

}

return null;

}

@Override

protected void onCancelled() {

super.onCancelled();

}

@Override

protected void onPostExecute(String result) {

// 返回HTML页面的内容

message.setText(result);

}

@Override

protected void onPreExecute() {

// 任务启动，可以在这里显示一个对话框，这里简单处理

message.setText(R.string.task_started);

}

@Override

protected void onProgressUpdate(Integer... values) {

// 更新进度

message.setText(values[0]);

}

}

// 设置三种类型参数分别为String,Integer,String

class PageTask extends AsyncTask {

// 可变长的输入参数，与AsyncTask.exucute()对应

@Override

protected String doInBackground(String... params) {

try {

HttpClient client = new DefaultHttpClient();

// params[0]代表连接的url

HttpGet get = new HttpGet(params[0]);

HttpResponse response = client.execute(get);

HttpEntity entity = response.getEntity();

long length = entity.getContentLength();

InputStream is = entity.getContent();