Why Does This Code Take A Long Time?

I am using this following code for getting all songs stored in the sdcard. https://stackoverflow.com/a/12227047/2714061 Well why does this code take so long to return this list of

Solution 1:

How about using an asynchronous task, reading a file or downloading something, takes time that requires the user to wait, you must think of using an Asynchronous task for this purpose,

1: From the developer reference we have : AsyncTask enables proper and easy use of the UI thread. This class allows to perform background operations and publish results on the UI thread without having to manipulate threads and/or handlers. http://developer.android.com/reference/android/os/AsyncTask.html

An asynchronous task is defined by 3 generic types, called Params, Progress and Result, and 4 steps, called onPreExecute, doInBackground, onProgressUpdate and onPostExecute.

2: So you may include an Async task class as:

classDoBackgroundTaskextendsAsyncTask<URL, Void, ArrayList> {
           /*
             URL is the file directory or URL to be fetched, remember we can pass an array of URLs, 
            Void is simple void for the progress parameter, you may change it to Integer or Double if you also want to do something on progress,
            Arraylist is the type of object returned by doInBackground() method.

           */@OverrideprotectedArrayListdoInBackground(URL... url) {
     //Do your background work here//i.e. fetch your file list herereturn fileList; // return your fileList as an ArrayList

    }

    protectedvoidonPostExecute(ArrayList result) {

    //Do updates on GUI here//i.e. fetch your file list from result and show on GUI

    }

    @OverrideprotectedvoidonProgressUpdate(Integer... values) {
        // Do something on progress update
    }

}
//Meanwhile, you may show a progressbar while the files load, or are fetched.

This AsyncTask can be called from you onCreate method by calling its execute method and passing the arguments to it:

 new DoBackgroundTask().execute(URL);

3: And at last, there is also a very nice tutorial about AsyncTasks here, http://www.vogella.com/articles/AndroidBackgroundProcessing/article.html