顯示進度百分比複製文件

Question

目前

我選擇從庫文件並將其複製到指定的文件夾。在複製時，我顯示ProgressDialog，我正在使用AsyncTask。

我試圖顯示正在複製的文件的進度百分比，但我遇到的問題是進度顯示50％，並保持在50％，直到文件完成複製。

有很多關於此的問題，但所有這些都與從URL下載有關。

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我的問題

我怎樣才能得到文件的當前進度被複制並使其顯示爲百分比是多少？

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請看看我已經試過如下：

@Override 
protected void onActivityResult(int requestCode, int resultCode, Intent data) 
{ 
    if(requestCode == SELECT_VIDEO_REQUEST && resultCode == RESULT_OK) 
    { 
     if(data.getData()!=null) 
     { 
      new MyCopyTask().execute(data.getData()); 

    }else{ 

     Toast.makeText(getApplicationContext(), "Failed to select video" , Toast.LENGTH_LONG).show(); 

     } 
    } 
} 

private class MyCopyTask extends AsyncTask<Uri, Integer, File> { 
    ProgressDialog progressDialog; 

    @Override 
    protected void onPreExecute() { 
     progressDialog = new ProgressDialog(MainActivity.this); 
     progressDialog.setCancelable(false); 
     progressDialog.setIndeterminate(false); 
     progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); 
     progressDialog.setMax(100); 
     progressDialog.show(); 
    } 


    @Override 
    protected File doInBackground(Uri... params) { 
     //copy file to new folder 
     Uri selectedImageUri = params[0]; 
     String sourcePath = getRealPathFromURI(selectedImageUri); 

     File source = new File(sourcePath); 



     String filename = sourcePath.substring(sourcePath.lastIndexOf("/")+1); 

     //onProgressUpdate(50); 

     publishProgress(50); 

     File destination = new File(Environment.getExternalStorageDirectory(), "MyFolder/Videos/"+filename); 
     try 
     { 
      FileUtils.copyFile(source, destination); 
     } 
     catch (IOException e) 
     { 
      e.printStackTrace(); 
     } 
     return destination; 
    } 

    @Override 
    protected void onProgressUpdate(Integer... values){ 
     super.onProgressUpdate(values); 
     progressDialog.setProgress(values[0]); 
    } 


    @Override 
    protected void onPostExecute(File result) { 
     if(result.exists()) { 
      sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.fromFile(result))); 

      Toast.makeText(getApplicationContext(),"Stored at: "+"---"+result.getParent()+"----"+"with name: "+result.getName(), Toast.LENGTH_LONG).show(); 
      progressDialog.dismiss(); 


     } else { 
      Toast.makeText(getApplicationContext(),"File could not be copied", Toast.LENGTH_LONG).show(); 
      progressDialog.dismiss(); 
     } 

    } 



} 

Answer 1

手動複製和更新百分比進度：

InputStream in = new FileInputStream(source); 
OutputStream out = new FileOutputStream(destination); 

long lenghtOfFile = source.length(); 
byte[] buf = new byte[512]; 
int len; 
long total; 
while ((len = in.read(buf)) != -1) { 
    total += len; 

    publishProgress((int)((total*100)/lenghtOfFile)); 
    out.write(buf, 0, len); 
} 

in.close(); 
out.close(); 

Answer 2

錯誤是publishProgress（50）; 你必須發佈每個百分比的進度 這樣 publishProgress（i）; i ++;