我创建了一个用于将文件上传到PHP服务器的程序。 它看起来像这样：
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
private static final int PICK_FILE_REQUEST = 1;
private static final String TAG = MainActivity.class.getSimpleName();
private String selectedFilePath;
private String SERVER_URL = "http://192.168.0.29/aji/AndroidFileUpload/UploadToServer.php";
ImageView ivAttachment;
Button bUpload;
TextView tvFileName;
ProgressDialog dialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ivAttachment = (ImageView) findViewById(R.id.ivAttachment);
bUpload = (Button) findViewById(R.id.b_upload);
tvFileName = (TextView) findViewById(R.id.tv_file_name);
ivAttachment.setOnClickListener(this);
bUpload.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if(v== ivAttachment){
//on attachment icon click
showFileChooser();
}
if(v== bUpload){
//on upload button Click
if(selectedFilePath != null){
dialog = ProgressDialog.show(MainActivity.this,"","Uploading File...",true);
new Thread(new Runnable() {
@Override
public void run() {
//creating new thread to handle Http Operations
uploadFile(selectedFilePath);
}
}).start();
}else{
Toast.makeText(MainActivity.this,"Please choose a File First",Toast.LENGTH_SHORT).show();
}
}
}
private void showFileChooser() {
Intent intent = new Intent();
//sets the select file to all types of files
intent.setType("file/*");
//allows to select data and return it
intent.setAction(Intent.ACTION_GET_CONTENT);
//starts new activity to select file and return data
startActivityForResult(Intent.createChooser(intent,"Choose File to Upload.."),PICK_FILE_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == Activity.RESULT_OK){
if(requestCode == PICK_FILE_REQUEST){
if(data == null){
//no data present
return;
}
Uri selectedFileUri = data.getData();
selectedFilePath = FilePath.getPath(this,selectedFileUri);
Log.i(TAG,"Selected File Path:" + selectedFilePath);
if(selectedFilePath != null && !selectedFilePath.equals("")){
tvFileName.setText(selectedFilePath);
}else{
Toast.makeText(this,"Cannot upload file to server",Toast.LENGTH_SHORT).show();
}
}
}
}
//android upload file to server
public int uploadFile(final String selectedFilePath){
int serverResponseCode = 0;
HttpURLConnection connection;
DataOutputStream dataOutputStream;
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead,bytesAvailable,bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 1024 * 1024;
File selectedFile = new File(selectedFilePath);
String[] parts = selectedFilePath.split("/");
final String fileName = parts[parts.length-1];
if (!selectedFile.isFile()){
dialog.dismiss();
runOnUiThread(new Runnable() {
@Override
public void run() {
tvFileName.setText("Source File Doesn't Exist: " + selectedFilePath);
}
});
return 0;
}else{
try{
FileInputStream fileInputStream = new FileInputStream(selectedFile);
URL url = new URL(SERVER_URL);
connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);//Allow Inputs
connection.setDoOutput(true);//Allow Outputs
connection.setUseCaches(false);//Don't use a cached Copy
connection.setRequestMethod("POST");
connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("ENCTYPE", "multipart/form-data");
connection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
connection.setRequestProperty("uploaded_file",selectedFilePath);
//creating new dataoutputstream
dataOutputStream = new DataOutputStream(connection.getOutputStream());
//writing bytes to data outputstream
dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
dataOutputStream.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\""
+ selectedFilePath + "\"" + lineEnd);
dataOutputStream.writeBytes(lineEnd);
//returns no. of bytes present in fileInputStream
bytesAvailable = fileInputStream.available();
//selecting the buffer size as minimum of available bytes or 1 MB
bufferSize = Math.min(bytesAvailable,maxBufferSize);
//setting the buffer as byte array of size of bufferSize
buffer = new byte[bufferSize];
//reads bytes from FileInputStream(from 0th index of buffer to buffersize)
bytesRead = fileInputStream.read(buffer,0,bufferSize);
//loop repeats till bytesRead = -1, i.e., no bytes are left to read
while (bytesRead > 0){
//write the bytes read from inputstream
dataOutputStream.write(buffer,0,bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable,maxBufferSize);
bytesRead = fileInputStream.read(buffer,0,bufferSize);
}
dataOutputStream.writeBytes(lineEnd);
dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
serverResponseCode = connection.getResponseCode();
String serverResponseMessage = connection.getResponseMessage();
Log.i(TAG, "Server Response is: " + serverResponseMessage + ": " + serverResponseCode);
//response code of 200 indicates the server status OK
if(serverResponseCode == 200){
runOnUiThread(new Runnable() {
@Override
public void run() {
tvFileName.setText("File Upload completed.\n\n You can see the uploaded file here: \n\n" + "http://coderefer.com/extras/uploads/"+ fileName);
}
});
}
//closing the input and output streams
fileInputStream.close();
dataOutputStream.flush();
dataOutputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MainActivity.this,"File Not Found",Toast.LENGTH_SHORT).show();
}
});
} catch (MalformedURLException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, "URL error!", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, "Cannot Read/Write File!", Toast.LENGTH_SHORT).show();
}
dialog.dismiss();
return serverResponseCode;
}
}
}
并且对于文件路径：
public class FilePath {
/**
* Method for return file path of Gallery image/ Document / Video / Audio
*
* @param context
* @param uri
* @return path of the selected image file from gallery
*/
@TargetApi(Build.VERSION_CODES.KITKAT)
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)) {
return Environment.getExternalStorageDirectory() + "/"
+ 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())) {
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());
}
}
当我在安卓4.0系统上运行时，它可以正常工作。 但是当我在安卓6.0系统上运行时，文件无法被点击。
效果如下图所示：
getPath方法永远无法适用于所有文件。您应该使用 ContentResolver.openInputStream()，它适用于您收到的每个 URI。只需跳过整个方法即可。 - ianhanniballakeopenInputStream()的原因。 - ianhanniballake