我已经坚持了一段时间。我有一个异步任务，将图像上传到Web服务器。工作正常。
我为此设置了一个进度条对话框。我的问题是如何准确更新进度条。我尝试的所有东西都会导致它从一步到0-100。如果需要5秒或2分钟则无关紧要。上传完成后，栏会挂到0，然后点击100。
这是我的doInBackground代码。任何帮助表示赞赏。
编辑：我更新了以下代码以包含整个AsynchTask
private class UploadImageTask extends AsyncTask<String,Integer,String> {
private Context context;
private String msg = "";
private boolean running = true;
public UploadImageTask(Activity activity) {
this.context = activity;
dialog = new ProgressDialog(context);
dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
dialog.setMessage("Uploading photo, please wait.");
dialog.setMax(100);
dialog.setCancelable(true);
}
@Override
protected void onPreExecute() {
dialog.show();
dialog.setOnDismissListener(mOnDismissListener);
}
@Override
protected void onPostExecute(String msg){
try {
// prevents crash in rare case where activity finishes before dialog
if (dialog.isShowing()) {
dialog.dismiss();
}
} catch (Exception e) {
}
}
@Override
protected void onProgressUpdate(Integer... progress) {
dialog.setProgress(progress[0]);
}
@Override
protected String doInBackground(String... urls) {
if(running) {
// new file upload
HttpURLConnection conn = null;
DataOutputStream dos = null;
DataInputStream inStream = null;
String exsistingFileName = savedImagePath;
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead, bytesAvailable, bufferSize;
byte[] buffer;
int maxBufferSize = 1024 * 1024;
String urlString = "https://mysite.com/upload.php";
float currentRating = ratingbar.getRating();
File file = new File(savedImagePath);
int sentBytes = 0;
long fileSize = file.length();
try {
// ------------------ CLIENT REQUEST
// open a URL connection to the Servlet
URL url = new URL(urlString);
// Open a HTTP connection to the URL
conn = (HttpURLConnection) url.openConnection();
// Allow Inputs
conn.setDoInput(true);
// Allow Outputs
conn.setDoOutput(true);
// Don't use a cached copy.
conn.setUseCaches(false);
// Use a post method.
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("Content-Type","multipart/form-data;boundary=" + boundary);
dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos.writeBytes("Content-Disposition: form-data; name=\"uploadedfile\";filename=\""
+ exsistingFileName + "\"" + lineEnd);
dos.writeBytes(lineEnd);
FileInputStream fileInputStream = new FileInputStream(new File(exsistingFileName));
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
// read file and write it into form...
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dos.write(buffer, 0, bufferSize);
// Update progress dialog
sentBytes += bufferSize;
publishProgress((int)(sentBytes * 100 / fileSize));
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
}
// send multipart form data necesssary after file data...
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
dos.flush();
dos.close();
fileInputStream.close();
}catch (MalformedURLException e) {
}catch (IOException e) {
}
// ------------------ read the SERVER RESPONSE
try {
inStream = new DataInputStream(conn.getInputStream());
// try to read input stream
// InputStream content = inStream.getContent();
BufferedInputStream bis = new BufferedInputStream(inStream);
ByteArrayBuffer baf = new ByteArrayBuffer(20);
long total = 0;
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
/* Convert the Bytes read to a String. */
String mytext = new String(baf.toByteArray());
final String newtext = mytext.trim();
inStream.close();
} catch (Exception e) {
}
}
return msg;
}
}
答案 0 :(得分：11)
这应该有效！
connection = (HttpURLConnection) url_stripped.openConnection();
connection.setRequestMethod("PUT");
String boundary = "---------------------------boundary";
String tail = "\r\n--" + boundary + "--\r\n";
connection.addRequestProperty("Content-Type", "image/jpeg");
connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("Content-Length", ""
+ file.length());
connection.setDoOutput(true);
String metadataPart = "--"
+ boundary
+ "\r\n"
+ "Content-Disposition: form-data; name=\"metadata\"\r\n\r\n"
+ "" + "\r\n";
String fileHeader1 = "--"
+ boundary
+ "\r\n"
+ "Content-Disposition: form-data; name=\"uploadfile\"; filename=\""
+ fileName + "\"\r\n"
+ "Content-Type: application/octet-stream\r\n"
+ "Content-Transfer-Encoding: binary\r\n";
long fileLength = file.length() + tail.length();
String fileHeader2 = "Content-length: " + fileLength + "\r\n";
String fileHeader = fileHeader1 + fileHeader2 + "\r\n";
String stringData = metadataPart + fileHeader;
long requestLength = stringData.length() + fileLength;
connection.setRequestProperty("Content-length", ""
+ requestLength);
connection.setFixedLengthStreamingMode((int) requestLength);
connection.connect();
DataOutputStream out = new DataOutputStream(
connection.getOutputStream());
out.writeBytes(stringData);
out.flush();
int progress = 0;
int bytesRead = 0;
byte buf[] = new byte[1024];
BufferedInputStream bufInput = new BufferedInputStream(
new FileInputStream(file));
while ((bytesRead = bufInput.read(buf)) != -1) {
// write output
out.write(buf, 0, bytesRead);
out.flush();
progress += bytesRead;
// update progress bar
publishProgress(progress);
}
// Write closing boundary and close stream
out.writeBytes(tail);
out.flush();
out.close();
// Get server response
BufferedReader reader = new BufferedReader(
new InputStreamReader(connection.getInputStream()));
String line = "";
StringBuilder builder = new StringBuilder();
while ((line = reader.readLine()) != null) {
builder.append(line);
}
参考：http://delimitry.blogspot.in/2011/08/android-upload-progress.html
答案 1 :(得分：2)
你可以这样做：
try { // open a URL connection to the Servlet
FileInputStream fileInputStream = new FileInputStream(
sourceFile);
URL url = new URL("http://10.0.2.2:9090/plugins/myplugin/upload");
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true); // Allow Inputs
conn.setDoOutput(true); // Allow Outputs
conn.setUseCaches(false); // Don't use a Cached Copy
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("ENCTYPE", "multipart/form-data");
conn.setRequestProperty("Content-Type",
"multipart/form-data;boundary=" + boundary);
conn.setRequestProperty("uploadedfile", filename);
// conn.setFixedLengthStreamingMode(1024);
// conn.setChunkedStreamingMode(1);
dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos.writeBytes("Content-Disposition: form-data; name=\"uploadedfile\";filename=\""
+ filename + "\"" + lineEnd);
dos.writeBytes(lineEnd);
bytesAvailable = fileInputStream.available();
bufferSize = (int) sourceFile.length()/200;//suppose you want to write file in 200 chunks
buffer = new byte[bufferSize];
int sentBytes=0;
// read file and write it into form...
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dos.write(buffer, 0, bufferSize);
// Update progress dialog
sentBytes += bufferSize;
publishProgress((int)(sentBytes * 100 / bytesAvailable));
bytesAvailable = fileInputStream.available();
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
}
// send multipart form data necesssary after file data...
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
// Responses from the server (code and message)
serverResponseCode = conn.getResponseCode();
String serverResponseMessage = conn.getResponseMessage();
// close streams
fileInputStream.close();
dos.flush();
dos.close();
} catch (MalformedURLException ex) {
ex.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
答案 2 :(得分：2)
我有同样的问题，这对我有帮助。这对你也有帮助。
在Async任务类中，编写（粘贴）以下代码。
ProgressDialog dialog;
protected void onPreExecute(){
//example of setting up something
dialog = new ProgressDialog(your_activity.this);
dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
dialog.setMax(100);
dialog.show();
}
@Override
protected String doInBackground(String... params) {
for (int i = 0; i < 20; i++) {
publishProgress(5);
try {
Thread.sleep(88);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
dialog.dismiss();
return null;
}
protected void onProgressUpdate(Integer...progress){
dialog.incrementProgressBy(progress[0]);
}
如果发生错误，请从代码中删除"publishProgress(5);"。否则很高兴。
答案 3 :(得分：0)
您需要对浮点值进行除法并将结果转换回int：
float progress = ((float)sentBytes/(float)fileSize)*100.0f;
publishProgress((int)progress);
答案 4 :(得分：0)
我花了两天with this example。
这一切都在这个字符串中。
conn.setRequestProperty("ENCTYPE", "multipart/form-data");
只有它有帮助。