Android從onActivityResult獲取文件名和路徑

Question

我試圖實現的目標。我有一個button，當按鈕被點擊時，應用程序打開一個文件選擇器，用戶選擇一個文件。該應用程序然後使用FileInputStream來讀取文件並生成byte[]。我在button下面有一個TextView，然後它將只顯示byte[].length。下面是在button.onClick()事件中的代碼：

Intent intent = new Intent(Intent.ACTION_GET_CONTENT); 
    intent.addCategory(Intent.CATEGORY_OPENABLE); 
    intent.setType("*/*"); 

    requestFilePickerCode = parent.registerActivityResultListener(this); 
    try 
    { 
     parent.startActivityForResult(intent, requestFilePickerCode); 
    } 
    catch (ActivityNotFoundException e) 
    { 
     Toast.makeText(task.getParent(), "Please install a file manager", Toast.LENGTH_SHORT).show(); 
    } 

現在這個代碼的工作，我已經證實，它激發onActivityResult選擇文件時。我簡單地打印Log顯示data.toString()產生以下輸出：

11-02 15:14:36.196 2535-2535/? V/class za.co.gpsts.gpsjobcard.utility.handlers.PebbleTypeHandlerBinary: -----> content:/com.android.providers.downloads.documents/document/1 

所以似乎越來越選定的文件。當我運行的應用程序，我選擇一個文件，它拋出我的自定義錯誤：

11-02 15:14:36.196 2535-2535/? E/class za.co.gpsts.gpsjobcard.utility.handlers.PebbleTypeHandlerBinary: -----> File does not exist 

這顯然表明，我沒有得到的文件。這裏是我的代碼：

@Override 
public boolean onActivityResult(int requestCode, int resultCode, Intent data) 
{ 
    byte[] fileContent; 

    // check that data is not null and assign to file if not null 
    if (data != null) 
    { 
     Uri uri = data.getData(); 
     String uriString = uri.toString(); 
     file = new File(uriString); 

     Log.v(PebbleTypeHandlerBinary.class.toString(), "-----> " + file.toString()); 

     // declare file input stream and read bytes 
     // write to string variable to test and test output 
     FileInputStream fin = null; 
     try 
     { 
      fin = new FileInputStream(file); 
      fileContent = new byte[(int) file.length()]; 

      fin.read(fileContent); 
      String test = new String(fileContent); 
      Log.v(PebbleTypeHandlerBinary.class.toString(), "=====> " + test); 
     } 
     catch (FileNotFoundException e) 
     { 
      Toast.makeText(task.getParent(), "File not found", Toast.LENGTH_SHORT).show(); 
      Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> File does not exist"); 
     } 
     catch (IOException e) 
     { 
      Toast.makeText(task.getParent(), "Error reading file", Toast.LENGTH_SHORT).show(); 
      Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> Error while reading the file"); 
     } 
     finally 
     { 
      // close the file input stream to stop mem leaks 
      try 
      { 
       if (fin != null) 
       { 
        fin.close(); 
       } 
      } catch (IOException e) 
      { 
       Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> Error closing the stream"); 
      } 
     } 

     Log.v(PebbleTypeHandlerBinary.class.toString(), data.toString()); 
    } 

    return false; 
} 

請你們可以查看我的代碼，並幫助我得到這個工作。任何幫助，將不勝感激。

Answer 1

U可搜索將uri轉換爲filepath。

GetData() retruns a uri。

但是​​需要filepath參數;

像這樣：

public static String getRealFilePath(final Context context, final Uri uri) { 
    if (null == uri) return null; 
    final String scheme = uri.getScheme(); 
    String data = null; 
    if (scheme == null) 
     data = uri.getPath(); 
    else if (ContentResolver.SCHEME_FILE.equals(scheme)) { 
     data = uri.getPath(); 
    } else if 
(ContentResolver.SCHEME_CONTENT.equals(scheme)) { 

Cursor cursor = context.getContentResolver().query(uri, new String[] { ImageColumns.DATA }, null, null, null); 
     if (null != cursor) { 
      if (cursor.moveToFirst()) { 

int index = cursor.getColumnIndex(ImageColumns.DATA); 
       if (index > -1) { 
        data = cursor.getString(index); 
       } 
      } 
      cursor.close(); 
     } 
    } 
    return data; 
} 

Answer 2

我設法如下解決它：

我以前inputStream = task.getParent().getContentResolver().openInputStream(uri);得到一個InputStream。然後使用ByteArrayOutputStream寫入一個字節[]。見下面的代碼。

@Override 
public boolean onActivityResult(int requestCode, int resultCode, Intent data) 
{ 
    Uri uri = data.getData(); 
    byte[] fileContent; 
    InputStream inputStream = null; 

    try 
    { 
     inputStream = task.getParent().getContentResolver().openInputStream(uri); 
     if (inputStream != null) 
     { 
      fileContent = new byte[(int)file.length()]; 
      inputStream.read(fileContent); 
      fileContent = new byte[1024]; 
      ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
      int read; 
      while((read=inputStream.read(fileContent))>-1) baos.write(fileContent,0,read); 
      fileContent = baos.toByteArray(); 
      baos.close(); 
      Log.v(PebbleTypeHandlerBinary.class.toString(), "-----> Input Stream: " + inputStream); 
      Log.v(PebbleTypeHandlerBinary.class.toString(), "-----> Byte Array: " + fileContent.length); 
     } 
     else 
     { 
      Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> Input Stream is null"); 
     } 
    } 
    catch (FileNotFoundException e) 
    { 
     Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> File not found", e); 
    } 
    catch (IOException e) 
    { 
     Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> Error reading file", e); 
    } 
    finally 
    { 
     if (inputStream != null) 
     { 
      try 
      { 
       inputStream.close(); 
      } 
      catch (IOException e) 
      { 
       Log.e(PebbleTypeHandlerBinary.class.toString(), "-----> Error reading file", e); 
      } 
     } 
    } 

    return false; 
} 

感謝您的幫助。