Deleting files in Android

Fresher picture Fresher · Jan 10, 2012 · Viewed 9k times · Source

I have a directory that contains a lot of files. I want to delete the entire directory as well as all the files in it.

I want my code to wait until every File in that directory (including the directory itself) is deleted before the next command is executed.

How do i wait? My code is

public void wipeMemoryCard() 
    {
        File deleteMatchingFile = new File(Environment 
                .getExternalStorageDirectory().toString()); 
        try { 
            filenames = deleteMatchingFile.listFiles(); 
            if (filenames != null && filenames.length > 0) 
            { 
                content = true;
                for (File tempFile : filenames) 
                { 
                    if (tempFile.isDirectory()) 
                    { 
                        wipeDirectory(tempFile.toString()); 
                        tempFile.delete();

                    } 
                    else 
                    {                       
                        File file = new File(tempFile.getAbsolutePath()); 
                        file.delete(); 
                    } 
                } 
            } 
            else 
            {   

                deleteMatchingFile.delete(); 
                Toast("No files to Delete");
            } 
        } 

        catch (Exception e) 
        { 
           e.printStackTrace();
        }
        if(content == true)
        {
              if (filenames == null && filenames.length == 0) 
              {
                  Toast("Files Deleted");
              }
        }
    } 

    private static void wipeDirectory(String name) { 
        File directoryFile = new File(name); 
        File[] filenames = directoryFile.listFiles(); 
        if (filenames != null && filenames.length > 0) 
        { 
            for (File tempFile : filenames) 
            { 
                if (tempFile.isDirectory()) 
                { 
                    wipeDirectory(tempFile.toString()); 
                    tempFile.delete(); 
                }
                else 
                { 
                    File file = new File(tempFile.getAbsolutePath()); 
                    file.delete();  
                } 
            } 
        } else 
        { 
            directoryFile.delete(); 
        } 
    } 

Answer

Ted Hopp picture Ted Hopp · Jan 10, 2012

You should not run this on the UI thread. If the file deletion takes too long, the system will pop up an "Application Not Responding" error. You can do this with an AsyncTask. The documentation shows a simple way to use this to pop up a "please wait" dialog, do the time-consuming work in the background, and then dismiss the dialog.

P.S. Your method name is kind of scary! :)