我想将图像从SD卡上传到服务器。 所以我对后端代码有所了解，即如何上传文件。但我想知道我将如何提供用户从他的设备中选择图像上传到服务器。我可以创建这个应用程序的UI，要求用户选择一个图像并上传它？请帮助我我是android新手。图像上传逻辑如下： 我得到了解决方案，我正在使用此代码...
public class DialogFile extends Activity {
FileDialog fileDialog = null;
static String fileName="";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.onCreate(savedInstanceState);
File mPath = new File(Environment.getExternalStorageDirectory() + "//Gaurav-Test//");
fileDialog = new FileDialog(this, mPath);
fileDialog.setFileEndsWith(".txt");
fileDialog.addFileListener(new FileDialog.FileSelectedListener() {
public void fileSelected(File file) {
fileName = file.toString();
Log.d(getClass().getName(), "selected file " + file.toString());
UploadToServer uploadObj = new UploadToServer();
try {
uploadObj.execute().get();
} catch (InterruptedException e) {
Log.d("InterruptedException", e.getMessage());
e.printStackTrace();
} catch (ExecutionException e) {
Log.d("ExecutionException", e.getMessage());
e.printStackTrace();
}
}
});
fileDialog.showDialog();
}
然后在文件FileDilaog.java
中import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.os.Environment;
import android.util.Log;
public class FileDialog {
private static final String PARENT_DIR = "..";
private final String TAG = getClass().getName();
private String[] fileList;
private File currentPath;
public interface FileSelectedListener {
void fileSelected(File file);
}
public interface DirectorySelectedListener {
void directorySelected(File directory);
}
private ListenerList<FileSelectedListener> fileListenerList = new ListenerList<FileDialog.FileSelectedListener>();
private ListenerList<DirectorySelectedListener> dirListenerList = new ListenerList<FileDialog.DirectorySelectedListener>();
private final Activity activity;
private boolean selectDirectoryOption;
private String fileEndsWith;
/**
* @param activity
* @param initialPath
*/
public FileDialog(Activity activity, File path) {
this.activity = activity;
if (!path.exists()) path = Environment.getExternalStorageDirectory();
loadFileList(path);
}
/**
* @return file dialog
*/
public Dialog createFileDialog() {
Dialog dialog = null;
AlertDialog.Builder builder = new AlertDialog.Builder(activity);
builder.setTitle(currentPath.getPath());
if (selectDirectoryOption) {
builder.setPositiveButton("Select directory", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Log.d(TAG, currentPath.getPath());
fireDirectorySelectedEvent(currentPath);
}
});
}
builder.setItems(fileList, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
String fileChosen = fileList[which];
File chosenFile = getChosenFile(fileChosen);
if (chosenFile.isDirectory()) {
loadFileList(chosenFile);
dialog.cancel();
dialog.dismiss();
showDialog();
} else fireFileSelectedEvent(chosenFile);
}
});
dialog = builder.show();
return dialog;
}
public void addFileListener(FileSelectedListener listener) {
fileListenerList.add(listener);
}
public void removeFileListener(FileSelectedListener listener) {
fileListenerList.remove(listener);
}
public void setSelectDirectoryOption(boolean selectDirectoryOption) {
this.selectDirectoryOption = selectDirectoryOption;
}
public void addDirectoryListener(DirectorySelectedListener listener) {
dirListenerList.add(listener);
}
public void removeDirectoryListener(DirectorySelectedListener listener) {
dirListenerList.remove(listener);
}
/**
* Show file dialog
*/
public void showDialog() {
createFileDialog().show();
}
private void fireFileSelectedEvent(final File file) {
fileListenerList.fireEvent(new FireHandler<FileDialog.FileSelectedListener>() {
public void fireEvent(FileSelectedListener listener) {
listener.fileSelected(file);
}
});
}
private void fireDirectorySelectedEvent(final File directory) {
dirListenerList.fireEvent(new FireHandler<FileDialog.DirectorySelectedListener>() {
public void fireEvent(DirectorySelectedListener listener) {
listener.directorySelected(directory);
}
});
}
private void loadFileList(File path) {
this.currentPath = path;
List<String> r = new ArrayList<String>();
if (path.exists()) {
if (path.getParentFile() != null) r.add(PARENT_DIR);
FilenameFilter filter = new FilenameFilter() {
public boolean accept(File dir, String filename) {
File sel = new File(dir, filename);
if (!sel.canRead()) return false;
if (selectDirectoryOption) return sel.isDirectory();
else {
boolean endsWith = fileEndsWith != null ? filename.toLowerCase().endsWith(fileEndsWith) : true;
return endsWith || sel.isDirectory();
}
}
};
String[] fileList1 = path.list(filter);
for (String file : fileList1) {
r.add(file);
}
}
fileList = (String[]) r.toArray(new String[]{});
}
private File getChosenFile(String fileChosen) {
if (fileChosen.equals(PARENT_DIR)) return currentPath.getParentFile();
else return new File(currentPath, fileChosen);
}
public void setFileEndsWith(String fileEndsWith) {
this.fileEndsWith = fileEndsWith != null ? fileEndsWith.toLowerCase() : fileEndsWith;
}
}
class ListenerList<L> {
private List<L> listenerList = new ArrayList<L>();
public interface FireHandler<L> {
void fireEvent(L listener);
}
public void add(L listener) {
listenerList.add(listener);
}
public void fireEvent(FireHandler<L> fireHandler) {
List<L> copy = new ArrayList<L>(listenerList);
for (L l : copy) {
fireHandler.fireEvent(l);
}
}
public void remove(L listener) {
listenerList.remove(listener);
}
public List<L> getListenerList() {
return listenerList;
}
}
然后将HTTPOST代码上传到服务器
import java.io.File;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import android.os.AsyncTask;
import android.util.Log;
public class UploadToServer extends AsyncTask<String, String, String>{
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... aurl){
String status="";
final String URL= "";
Log.d("Image Path ======",DialogFile.fileName);
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(URL);
File file = new File(DialogFile.fileName);
FileBody bin = new FileBody(file);
MultipartEntity reqEntity = new MultipartEntity();
reqEntity.addPart("userImage", bin);
httppost.setEntity(reqEntity);
Log.d("executing request ", httppost.getRequestLine().toString());
HttpResponse response = httpclient.execute(httppost);
HttpEntity resEntity = response.getEntity();
if (resEntity != null)
{
Log.d("Response content length: ",resEntity.getContentLength()+"");
if(resEntity.getContentLength()>0)
{
status= EntityUtils.toString(resEntity);
}
else
{
status= "No Response from Server";
Log.d("Status----->",status);
}
}
else
{
status= "No Response from Server";
Log.d("Status----->",status);
}
} catch (Exception e) {
e.printStackTrace();
status="Unable to connect with iPerform server";
}
return status;
}
}
答案 0 :(得分：0)
您可以查看此答案 https://stackoverflow.com/a/3645048/984466
例如，或使用自定义文件对话框 https://code.google.com/p/android-file-dialog/
答案 1 :(得分：0)
试试这个：
Intent intent = new Intent(Intent.ACTION_GET_CONTENT, null);
intent.setType("image/*");
intent.putExtra("return-data", true);
startActivityForResult(intent, 1);
然后此代码用于设置从图库中选择的图像。使用onActivityResult方法从Gallery中获取结果：
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case 1:
Uri _uri = data.getData();
String yourimagepath = getRealPathFromURI(_uri);
...
// your code goes here
}
super.onActivityResult(requestCode, resultCode, data);
}
public String getRealPathFromURI(Uri contentUri) {
String[] proj = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
希望它有所帮助。
答案 2 :(得分：0)
此代码可以帮助您：
String boundary = "---------------------------14737809831466499882746641449";
String lineEnd = "\r\n", p;
String twoHyphens = "--";
HttpURLConnection conn;
DataOutputStream dos = null;
int bytesRead, bytesAvailable, bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 1024 * 1024;
DataInputStream inStream;
File sourceFile;
ArrayList<String> tempList = new ArrayList<String>();
String exsistingFileName = Environment.getExternalStorageDirectory()
.getAbsolutePath() + "/PiyushAushFish";
try {
File f = new File(exsistingFileName);
File[] files = f.listFiles();
for (int i = 0; i < files.length; i++) {
File file = files[i];
tempList.add(file.getPath());
Log.v("Existing", exsistingFileName);
}
// tempList.add(exsistingFileName);
// tempList.add(FileName);
if (isUploaded) {
URL url = new URL(
"You URL here");
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type",
"text/plain; charset=utf-8");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("Content-Type",
"multipart/form-data; boundary=" + boundary);
for (int i = 0; i < tempList.size(); i++) {
Log.v("Length", tempList.size() + "");
sourceFile = new File(tempList.get(i));
FileInputStream fileInputStream = new FileInputStream(
sourceFile);
Log.v("IMAGPATH", sourceFile + "");
dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(lineEnd + twoHyphens + boundary + lineEnd);
System.out
.println("==========================image name================="
+ sourceFile);
dos.writeBytes("Content-Disposition: form-data; name=\"image[]\"; filename=\""
+ sourceFile + "\"" + lineEnd);
dos.writeBytes("Content-Type: application/octet-stream"
+ lineEnd + lineEnd);
System.out
.println("=============================data writin start================");
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dos.write(buffer, 0, bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
System.out
.println("==============================bytesRead==========================="
+ bytesRead);
}
dos.writeBytes(lineEnd + twoHyphens + boundary + twoHyphens
+ lineEnd);
fileInputStream.close();
}
dos.flush();
dos.close();
} else {
Log.v("Error.....", "No Data");
}
} catch (Exception e) {
// TODO Auto-generated catch block
Log.d("Error--------->", e.getMessage());
e.printStackTrace();
}
try {
inStream = new DataInputStream(conn.getInputStream());
String str;
while ((str = inStream.readLine()) != null) {
Log.e("Debug", "Server Response " + str);
}
inStream.close();
int serverResponseCode = conn.getResponseCode();
String serverResponseMessage = conn.getResponseMessage();
Log.e("server response codde", "" + serverResponseCode);
Log.i("uploadFile", "HTTP Response is : " + serverResponseMessage
+ ": " + serverResponseCode);
if (serverResponseCode == 200) {
isUploaded = true;
// isUploaded = (c.getInt(23) == 1);
Log.v("Upload", "Successfully");
}
} catch (IOException ioex) {
Log.e("Debug", "error: " + ioex.getMessage(), ioex);
}