If the value of the variable i is -1, then it indicates that the contents of the file are over 2GB. When the returned value is -1, you can use the function copyLarge inputStream, fileOS in place of the copy inputstream, fileOS function to handle this load.
Both of these functions buffer the inputstream internally. The internal buffer means we do not have to use the BufferedInputStream class to enhance our code performance and helps us avoid writing boilerplate code. Another library managed by the Apache organization is the HttpComponents package. This library uses the request-response mechanism to download the file from a given URL. The first step to downloading a file is to create an HTTP client object that would issue the request to the server.
For this, we will be using the CloseableHttpClient class. The code snippet that creates a new HTTP client is as follows:. We then need to create an HttpGet or HttpPost object to send the request to the server. The request is created by the following line of code:. The execute request function is applied to the client object and returns with a response from the server. Once the request is sent to the server we need a response object to receive the data sent from the server.
To catch the response from the server we use the HttpResponse class object. The data sent by the server in the form of a message is obtained through the getEntity function. You can also obtain the response code sent by the server through the response object and use it to your specific need. The data to be downloaded is encapsulated within the entity object and can be extracted using the getContent function. The getContent function returns an InputStream object that can be further used with a BufferedInputStreamReader to enhance performance.
Now all you need to do is read from the stream byte by byte and write the contents into a file using the FileOutputStream class. The last thing required to be done is closing all the open resources in order to ensure that the system resources are not overutilized and that there are no memory leaks. So there you have it - these are the simplest ways to download a file using the basic Java code and other third party libraries. Now that we are done with the basics, you can be as creative as you want and utilize the knowledge to suit your needs.
So see you next time with a new set of concepts to help you become a better coder. There's no easy way to fix it after the fact. So the initial effort of learning the basic, standard tools can be a good investment. This class was deprecated in API level ProgressDialog is a modal dialog, which prevents the user from interacting with the app. Instead of using this class, you should use a progress indicator like ProgressBar, which can be embedded in your app's UI.
Alternatively, you can use a notification to inform the user of the task's progress. For more details Link. Don't forget to add permissions to your manifest file if you're gonna be downloading stuff from the internet! Yes the code above will work. But if you are updating your progressbar in onProgressUpdate of Asynctask and you press back button or finish your activity AsyncTask looses its track with your UI. And when you go back to your activity, even if download is running in background you will see no update on progressbar.
So on OnResume try to run a thread like runOnUIThread with a timer task that updates ur progressbar with values updating from the AsyncTask running background. I'd recommend you to use my Project Netroid , It's based on Volley.
I have added some features to it such as multi-events callback, file download management. This could be of some help. I have modified AsyncTask class to handle creation of progressDialog at the same context. I think following code will be more reusable. I found this blog post very helpful, Its using loopJ to download file, it has only one Simple function, will be helpful to some new android guys.
While I was starting to learn android development, I had learnt that ProgressDialog is the way to go. There is the setProgress method of ProgressDialog which can be invoked to update the progress level as the file gets downloaded. The best I have seen in many apps is that they customize this progress dialog's attributes to give a better look and feel to the progress dialog than the stock version.
Any animation with in the progress dialog attracts users and they don't feel like being kept waiting for long. My personal advice is to use Progress Dialog and build up before execution , or initiate at OnPreExecute , publish progress often if you use horizontal style of progress bar of the progress dialog. The remaining part is to optimize the algorithm of doInBackground. Use Android Query library, very cool indeed. You can change it to use ProgressDialog as you see in other examples, this one will show progress view from your layout and hide it after completion.
I am adding another answer for other solution I am using now because Android Query is so big and unmaintained to stay healthy. You can observer the progress of the download manager using LiveData and coroutines, see the gist below. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more.
Asked 11 years, 5 months ago. Active 7 months ago. Viewed k times. Tom Leese Tom Leese I hope below link may be help you For quick fix refer this answer — Richa. Add a comment. Active Oldest Votes. Use AsyncTask and show the download progress in a dialog This method will allow you to execute some background processes and update the UI at the same time in this case, we'll update a progress bar.
Imports: import android. PowerManager; import java. InputStream; import java. OutputStream; import java. FileOutputStream; import java. Download from Service The big question here is: how do I update my activity from a service? This is how the whole code would look like: The activity where you are showing the dialog Use DownloadManager class GingerBread and newer only GingerBread brought a new feature, DownloadManager , which allows you to download files easily and delegate the hard work of handling threads, streams, etc.
Request Uri. Final thoughts First and second methods are just the tip of the iceberg. Make sure the directory were you are going to download files exist and has write permissions. If download is too big you may want to implement a way to resume the download if previous attempts failed.
Users will be grateful if you allow them to interrupt the download. There is a problem in Cristian's answer.
Because code at " 1. Use AsyncTask and show the download progress in a dialog " does connection. Suggested to close the streams input and output in finally instead of try , otherwise if any exception is thrown before close , you have unclosed streams hanging around. Animation sample program in Android. GridView sample program in Android. Reading a file sample program in Android. AlertDialog sample program in Android. Error generating R. Another Animation sample program in Android.
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Progress bar and downloading a file sample program in Android. Getting Started with Android. Android Emulator. I und. Perfect example and I have achieved my task.
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