我想通过最近遇到问题的多部分I Android Studio将PDF文件上传到服务器 这是有时可以正常工作的代码，并且PDF已成功发送到服务器，但是大多数情况下，它的路径值为null
String path = FilePath.getPath (this, filePath);
主要活动班
public class cv extends AppCompatActivity implements View.OnClickListener
{
//Declaring views
private Button buttonChoose;
private Button buttonUpload;
User user = SharedPrefManager.getInstance(this).getUser();
private EditText editText;
private PermissionObj permissionObj;
ImageView imageView;
//Image request code
private int PICK_PDF_REQUEST = 120;
//storage permission code
private static final int STORAGE_PERMISSION_CODE = 123;
//Bitmap to get image from gallery
private Bitmap bitmap;
//Uri to store the image uri
private Uri filePath;
//ListView to show the fetched Pdfs from the server
//button to fetch the intiate the fetching of pdfs.
Button buttonFetch;
//Progress bar to check the progress of obtaining pdfs
ProgressDialog progressDialog;
//an array to hold the different pdf objects
ArrayList<Pdf> pdfList = new ArrayList<Pdf>();
//pdf adapter
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_cv);
requestStoragePermission();
//Requesting storage permission
permissionObj = new PermissionObj(this);
//Initializing views
buttonChoose = (Button) findViewById(R.id.buttonChoose);
buttonUpload = (Button) findViewById(R.id.buttonUpload);
editText = (EditText) findViewById(R.id.editTextName);
//initializing buttonFetch
buttonFetch = (Button) findViewById(R.id.buttonFetchPdf);
//initializing progressDialog
progressDialog = new ProgressDialog(this);
//Setting clicklistener
buttonChoose.setOnClickListener(this);
buttonUpload.setOnClickListener(this);
buttonFetch.setOnClickListener(this);
}
/*
* This is the method responsible for image upload
* We need the full image path and the name for the image in this method
* */
public void uploadMultipart() {
//getting name for the pdf
String name = editText.getText().toString().trim();
//getting the actual path of the pdf
String path = FilePath.getPath(this,filePath);
Log.d("path", "Path: "+path);
if (path == null) {
Toast.makeText(this, "Please move your .pdf file to internal storage and retry", Toast.LENGTH_LONG).show();
} else {
//Uploading code
try {
String uploadId = UUID.randomUUID().toString();
//Creating a multi part request
new MultipartUploadRequest(this, uploadId, URLs.user_add_resume)
.addFileToUpload(path, "resume") //Adding file
.addParameter("user_id", String.valueOf(user.getId())) //Adding text parameter to the request
.addParameter("token", user.getapi_token()) //Adding text parameter to the request
.setNotificationConfig(new UploadNotificationConfig())
.setMaxRetries(2)
.startUpload(); //Starting the upload
} catch (Exception exc) {
Toast.makeText(this, exc.getMessage(), Toast.LENGTH_SHORT).show();
}
}
}
/* Get uri related content real local file path. */
//method to show file chooser
private void showFileChooser() {
Intent intent = new Intent();
intent.setType("application/pdf");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Pdf"), PICK_PDF_REQUEST);
}
//handling the ima chooser activity result
//handling the ima chooser activity result
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PICK_PDF_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null) {
filePath = data.getData();
}
}
//Requesting permission
private void requestStoragePermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED)
return;
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.READ_EXTERNAL_STORAGE)) {
//If the user has denied the permission previously your code will come to this block
//Here you can explain why you need this permission
//Explain here why you need this permission
}
//And finally ask for the permission
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, STORAGE_PERMISSION_CODE);
}
//This method will be called when the user will tap on allow or deny
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
//Checking the request code of our request
if (requestCode == STORAGE_PERMISSION_CODE) {
//If permission is granted
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
//Displaying a toast
Toast.makeText(this, "Permission granted now you can read the storage", Toast.LENGTH_LONG).show();
} else {
//Displaying another toast if permission is not granted
Toast.makeText(this, "Oops you just denied the permission", Toast.LENGTH_LONG).show();
}
}
}
@Override
public void onClick(View v) {
if (v == buttonChoose) {
requestStoragePermission();
showFileChooser();
}
if (v == buttonUpload) {
uploadMultipart();
}
if (v == buttonFetch) {
}
}
} 文件路径类
import android.annotation.SuppressLint;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.util.Log;
public class FilePath
{
/**
* Method for return file path of Gallery image
*
* @param context
* @param uri
* @return path of the selected image file from gallery
*/
@SuppressLint("NewApi")
public static String getPath(final Context context, final Uri uri)
{
//check here to KITKAT or new version
final boolean isKitKat = Build.VERSION.SDK_INT >=
Build.VERSION_CODES.KITKAT;
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
Log.d("envirment", "Path: "+Environment.getExternalStorageDirectory().getAbsolutePath() + "/" + split[1]);
return Environment.getExternalStorageDirectory().getAbsolutePath() + "/" + split[1];
}
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {
final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}
final String selection = "_id=?";
final String[] selectionArgs = new String[] {
split[1]
};
return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
Log.d("url.get", "Path: "+uri.getPath());
return uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
public static String getDataColumn(Context context, Uri uri, String selection,
String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {
column
};
try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.moveToFirst()) {
final int index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is Google Photos.
*/
public static boolean isGooglePhotosUri(Uri uri) {
return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}
}