創建和寫入Android設備/數據文件夾的文件

Question

嗨我需要創建和寫入文本文件到/ data目錄中。

這是我正在使用的代碼。

try { 
    Runtime runtime = Runtime.getRuntime(); 
    Process process = runtime.exec("chmod 777 /data"); 
    process.waitFor(); 

    resultFile = new File(Environment.getDataDirectory() 
          + "/resultfile.txt"); 
    Log.i(TAG,"File Object Created....."+resultFile); 
} catch (Exception e) { 
    Log.i(TAG, "Exception in Environment.getDataDirectory()" 
       + e.toString()); 
} 

try { 
    try { 
     Runtime runtime = Runtime.getRuntime(); 
     Process process = runtime.exec("chmod 777 /data/resultfile.txt"); 
     process.waitFor(); 

     if (!resultFile.exists()) 
      resultFile.createNewFile(); 

    } catch (IOException ioException) { 
     Log.i(TAG, "Exception in creating file..." 
        + ioException.toString()); 
    } 

    try { 
     if (fileWriter == null) 
      fileWriter = new FileWriter(resultFile); 
    } catch (FileNotFoundException fileNotFoundException) { 
      Log.i(TAG, "FileNotFoundException....." 
         + fileNotFoundException.toString()); 
    } 

，但我得到下面這些問題......

Exception in creating file...java.io.IOException: Permission denied 

FileNotFoundException.....java.io.FileNotFoundException: /data/resultfile.txt (Permission denied) 

Exception in saveResultsToFile.....java.lang.NullPointerException 

PLZ幫我在這...謝謝。

Answer 1

這將無法正常工作，因爲您沒有任何權限可在其中寫入。該目錄由root擁有。