title: android problem in extracting zip file using ZipFile
body: <p>try{</p>
  
  <pre><code>File f = new File("/data/cizip.zip");
   if(f.exists()){
     ZipFile zf = new ZipFile(f); //this always throws an error
  /*some of my codes here*/
  }
  catch(IOException e){
     AlertDialog.Builder abd = new AlertDialog.Builder(this);
     abd.setMessage(e.getMessage());
     abd.show();
  }
  </code></pre>
  
  <p>the line <code>ZipFile zf = new ZipFile(f);</code> always throws an error and I don't know why. And the error message is the file name ("/data/cizip.zip"), therefore I can't know the cause of the error. Can someone please tell me what causes this error? Thanks in advance.</p>