Download a file to your android device from a remote server with a Custom ProgressBar

First we will create a simple layout with a button that will download a file on it’s onClick event.

This is the contents of main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/btnDownload"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="66dp"
        android:onClick="downloadFile"
        android:text="Download File" />

    <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/btnDownload"
        android:layout_alignBottom="@+id/btnDownload"
        android:layout_alignParentLeft="true"
        android:text="Downloading File" />

</RelativeLayout>

Now we will write the java code to download the file.
Copy this code to your main java file. My file is named “DownLoadingFileActivity.java”.

package com.android;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.app.Activity;
import android.app.Dialog;
import android.content.ActivityNotFoundException;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

public class DownLoadingFileActivity extends Activity {
    /** Called when the activity is first created. */
    public Context context = this;
    ProgressBar pb;
    Dialog dialog;
    Button btnDownLoad;
    int downloadedSize = 0;
    int totalSize = 0;
    TextView cur_val;
    File file;
    String dwnload_file_path = "pdf file path from the server"; //pdf file path

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        btnDownLoad = (Button) findViewById(R.id.btnDownload);
        btnDownLoad.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                showProgress(dwnload_file_path);

                new Thread(new Runnable() {
                    public void run() {
                        downloadFile();
                    }
                }).start();

            }
        });
    }

    void showProgress(String file_path) {
        dialog = new Dialog(DownLoadingFileActivity.this);
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
        dialog.setContentView(R.layout.customprogressdialog);
        dialog.setTitle("Download Progress");

        TextView text = (TextView) dialog.findViewById(R.id.tvFileName);
        text.setText("Downloading file from ... " + file_path);
        cur_val = (TextView) dialog.findViewById(R.id.cur_pg_tv);
        cur_val.setText("Starting download...");
        dialog.show();

        pb = (ProgressBar) dialog.findViewById(R.id.progress_bar);
        pb.setProgress(0);
        pb.setProgressDrawable(getResources().getDrawable(
                R.drawable.progressbarstyle));
    }

    void downloadFile() {

        try {
            URL url = new URL(dwnload_file_path);
            HttpURLConnection urlConnection = (HttpURLConnection) url
                    .openConnection();

            urlConnection.setRequestMethod("GET");
            urlConnection.setDoOutput(true);

            // connect
            urlConnection.connect();

            // set the path where we want to save the file
            File SDCardRoot = Environment.getExternalStorageDirectory();
            // create a new file, to save the downloaded file
            file = new File(SDCardRoot, "downloaded_file.pdf");

            FileOutputStream fileOutput = new FileOutputStream(file);

            // Stream used for reading the data from the internet
            InputStream inputStream = urlConnection.getInputStream();

            // this is the total size of the file which we are downloading
            totalSize = urlConnection.getContentLength();

            runOnUiThread(new Runnable() {
                public void run() {
                    pb.setMax(totalSize);
                }
            });

            // create a buffer...
            byte[] buffer = new byte[1024 * 1024];
            int bufferLength = 0;

            while ((bufferLength = inputStream.read(buffer)) > 0) {
                fileOutput.write(buffer, 0, bufferLength);
                downloadedSize += bufferLength;
                // update the progressbar //
                runOnUiThread(new Runnable() {
                    public void run() {
                        pb.setProgress(downloadedSize);
                        float per = ((float) downloadedSize / totalSize) * 100;
                        cur_val.setText("Downloaded " + downloadedSize
                                + "KB / " + totalSize + "KB (" + (int) per
                                + "%)");
                    }
                });
            }
            // close the output stream when complete //
            fileOutput.close();
            runOnUiThread(new Runnable() {
                public void run() {
                    // pb.dismiss(); // if you want close it..
                    Uri path = Uri.fromFile(file);
                    try {
                        Intent intent = new Intent(Intent.ACTION_VIEW);
                        intent.setDataAndType(path, "application/pdf");
                        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        startActivity(intent);
                        finish();
                    } catch (ActivityNotFoundException e) {
                        Toast.makeText(
                                context,
                                "PDF Reader application is not installed in your device",
                                Toast.LENGTH_SHORT).show();

                    }
                }
            });

        } catch (final MalformedURLException e) {
            showError("Error : MalformedURLException " + e);
            e.printStackTrace();
        } catch (final IOException e) {
            showError("Error : IOException " + e);
            e.printStackTrace();
        } catch (final Exception e) {
            showError("Error : Please check your internet connection " + e);
        }
    }

    void showError(final String err) {
        runOnUiThread(new Runnable() {
            public void run() {
                Toast.makeText(DownLoadingFileActivity.this, err,
                        Toast.LENGTH_LONG).show();
            }
        });
    }

}

Ok now we have to make a layout for the progressdialog since it is a custom one.
Create a new XML file inside res/layout folder and name it customprogressdialog.xml and copy this code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout_root"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:padding="10dp" >

    <TextView
        android:id="@+id/tvFileName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="FileName"
        android:textColor="#FFF"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/cur_pg_tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:text="hello"
        android:textColor="#0F0"
        android:textStyle="bold|italic" />

    <ProgressBar
        android:id="@+id/progress_bar"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="10dp"
        android:layout_marginTop="5dp"
        android:maxHeight="10dip"
        android:minHeight="10dip"
        android:progress="0" />

</LinearLayout>

Now create a new file inside res/drawable folder and name it “progressbarstyle.xml” and copy this code into it.
This xml is used for giving a green color to the progressbar.

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >

    <item android:id="@android:id/background">

        <shape >

            <corners android:radius="5dip" />

            <gradient
                android:angle="270"
                android:centerColor="#ff5a5d5a"
                android:centerY="0.75"
                android:endColor="#ff747674"
                android:startColor="#ff9d9e9d" />
        </shape>
    </item>

    <item android:id="@android:id/progress">

        <clip >

            <shape >

                <corners android:radius="5dip" />

                <gradient
                    android:angle="270"
                    android:centerColor="@color/greenMid"
                    android:centerY="0.75"
                    android:endColor="@color/greenEnd"
                    android:startColor="@color/greenStart" />
            </shape>
        </clip>
    </item>

</layer-list>

color.xml
-----------
<?xml version="1.0" encoding="utf-8"?>
<resources>

    <color name="greenStart">#ff33dd44</color>
    <color name="greenMid">#ff0A8815</color>
    <color name="greenEnd">#ff1da130</color>

</resources>

Ok now we have customized the progressbar.
This line sets the progressbar to green color.

pb.setProgressDrawable(getResources().getDrawable(R.drawable.progressbarstyle));

The showProgress() method inside the java code will invoke the custom progressbar.
Now the main thing..
Dont forget to add the permissions to the manifest file.
These two are the permissions we need .

This is the AndroidManifest file for this example.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.android"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="8" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <activity
            android:label="@string/app_name"
            android:name=".DownLoadingFileActivity" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>