How to Use Android Downloads Provider

“Good programmers write solid code, while great programmers reuse the code of good programmers”
— W. Jason Gilmore, the author of “Beginning PHP and MySQL”

In Android Platform, it supports some ways to download files from URLs via HttpURLConnection or HttpClient, or DownloadProvider.When you write an android programm with Eclipse, try to import:

import android.provider.Downloads

The Eclipse gives a red error prompting and complains:

The import android.provider.Downloads cannot be resolved

Oops…

The download manager is not part of the public SDK, and there are no relational API description in Android developers Reference.Comment in sources frameworks/base/core/java/android/provider/Downloads.java, says: “For 1.0 the download manager can’t deal with abuse from untrusted apps, so this API is hidden.” Refer to the document description from: packages/providers/DownloadProvider/docs/index.html. we Know that Browser / Gmail / Market / Updater depend on the download manager. Yes, show some screenshots in the market:

use downloadprovider in android market

android market downloads shows in the statebar.

We maybe can’t compile with Eclipse, but we can write an Android.mk makefile, use mmm to do it.

DownloadProvider is very easy to use.First, declare permission in AndroidManifest.xml:

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

And then just need to fill some field values:

ContentValues values = new ContentValues();
String url = "http://lytsing.qiniudn.com/wp-content/uploads/2010/06/android_downloadprovider_market.jpg";
values.put(Downloads.URI, url);
values.put(Downloads.MIMETYPE, "image/jpeg");
values.put(Downloads.FILENAME_HINT, getFullFilename("android_downloadprovider_market.jpg"));
values.put(Downloads.TITLE, "screenshot");
values.put(Downloads.DESCRIPTION, "screenshot file for DownloadProvider Demo");
values.put(Downloads.VISIBILITY, Downloads.VISIBILITY_VISIBLE);
values.put(Downloads.NOTIFICATION_CLASS, "org.lytsting.android.downloads.DownloadReceiver");
values.put(Downloads.NOTIFICATION_PACKAGE, "org.lytsting.android.downloads");
getContentResolver().insert(Downloads.CONTENT_URI, values);

private String getFullFilename(String filename) {
    return Environment.getExternalStorageDirectory().toString() + "/download/" + filename);
}

Notes

Downloads.FILENAME_HINT, for a demo, here, I put the file into SD Card, the download directory, without checking any exception.
Downloads.NOTIFICATION_CLASS, you want to write a DownloadReceiver class, which extends BroadcastReceiver, and handle the message Downloads.DOWNLOAD_COMPLETED_ACTION or Downloads.NOTIFICATION_CLICKED_ACTION. like this:

public class DownloadReceiver extends BroadcastReceiver {
    static final String TAG = "DownloadReceiver";

    @Override
    public void onReceive(Context context, Intent intent) {
        Log.d(TAG, intent.getAction());
        if (intent.getAction().equals(Downloads.NOTIFICATION_CLICKED_ACTION)) {
            Intent activityIntent = new Intent(Intent.ACTION_VIEW);
            activityIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            activityIntent.setClass(context, Downloads.class); // Downloads Activity
            try {
                context.startActivity(activityIntent);
            } catch (ActivityNotFoundException ex) {
                Log.d(TAG, "no activity for Downloads.NOTIFICATION_CLICKED_ACTION" + ex);
            }
        } else if (intent.getAction().equals(Downloads.DOWNLOAD_COMPLETED_ACTION)) {
            // balabala
        }
    }
}

By here, we need to modify the AndroidManifest.xml, add:

<receiver
    android:name=".DownloadReceiver"
    android:permission="android.permission.SEND_DOWNLOAD_COMPLETED_INTENTS"
    android:exported="true" >
    
    <intent-filter>
        <action
            android:name="android.intent.action.DOWNLOAD_COMPLETED">
        </action>
    </intent-filter>
    <intent-filter>
        <action
            android:name="android.intent.action.DOWNLOAD_NOTIFICATION_CLICKED">
        </action>

        <category
            android:name="android.intent.category.DEFAULT">
        </category>
        <data
            android:scheme="content">
        </data>
    </intent-filter>
</receiver> 

Maybe, you don’t like show the the Download state in status bar, just change Downloads.VISIBILITY_VISIBLE to Downloads.VISIBILITY_HIDDEN

and even, maybe you would like to show the download progress in the Activity, little case.

Cursor c = getContentResolver().query(
        Downloads.CONTENT_URI, new String[] {
        Downloads._ID,
        Downloads.CURRENT_BYTES,
        Downloads.TOTAL_BYTES,
        Downloads.STATUS }, 
        " " + Downloads.MIMETYPE + " = 'image/jpeg'", null,
        Downloads._ID);

if (c == null) {
    return;
}

// Columns match projection in query above
final int idColumn = 0;
final int currentBytesColumn = 1;
final int totalBytesColumn = 2;
final int statusColumn = 3;

c.moveToFirst();
long totalBytes = c.getLong(totalBytesColumn);
long currentBytes = c.getLong(currentBytesColumn);

c.close();

Add a ProgressBar and a Handler to display and refresh the progress, I suppose you should know how to do. You also can write a class extends ContentObserver to observer the download status.

The last step, delete the history data:

getContentResolver().delete(Downloads.CONTENT_URI,
                 "(" + Downloads.TITLE + " = 'screenshot')", null);

This code snippet should be write into a function in really code.

Read the code packages/apps/Browser for a more complete example.

Update:Since Android 2.2, the Downloads’s api has changed, they put some variables input a sub class which named Impl, so you should check it in the source code.

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21 thoughts on “How to Use Android Downloads Provider

  1. kingmove

    We maybe can’t compile with Eclipse, but we can write an Android.mk makefile, use mmm to do it.

    How do?could you tell me more.thank you.

    Reply
    1. deli Post author

      hi kingmove:
      First, you want to compile all the android code, and then put your project to packages/apps/ , create Android.mk file in the root of your project, can refer to the Browser’s Android.mk, or others.
      . build/envsetup.sh
      mmm packages/apps/your_project

      Reply
      1. magic

        hi deli ,
        I can compile my code successfully with the method you mentioned and I push the apk file under the /system/app , but when I tried to run it on the device, it told me the error ” 09-03 08:53:37.696: ERROR/AndroidRuntime(3304): The import android.provider.Downloads cannot be resolved” .
        Why?

        Reply
          1. Rahul

            Hi,

            I am trying to do the same thing as you but I am new to the android and don’t know how write a make file. It would be great help if u can share ur mk file.

            Thanks in advance.

          2. lytsing Post author

            $ cat Android.mk
            LOCAL_PATH:= $(call my-dir)
            include $(CLEAR_VARS)

            LOCAL_MODULE_TAGS := user

            LOCAL_SRC_FILES := $(call all-java-files-under, src)

            LOCAL_SRC_FILES += \
            src/com/google/android/googleapps/IGoogleLoginService.aidl \
            src/com/android/vending/licensing/ILicenseResultListener.aidl\
            src/com/android/vending/licensing/ILicensingService.aidl

            LOCAL_PACKAGE_NAME := Vending
            LOCAL_CERTIFICATE := platform

            include $(BUILD_PACKAGE)

            include $(BUILD_MULTI_PREBUILT)

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  3. Darla

    Hi there. This is a very informative post. I am fairly new to developing on this platform, but I was very surprised to read this:

    “The download manager is not part of the public SDK, and there are no relational API description in Android developers Reference.”

    Maybe it’s my ignorance. However, it looks like you have provided a solid solution. I’ve bookmarked this page because I believe it will directly relate to some things I will be doing next month. Oh, and thanks for the update at the end too. :)

    Darla

    Reply
    1. deli Post author

      hi, If your apps have the same sign key with your ROM, or you can get the root user privileges, you can use the downloads Provider. If not, you can use the exists Downloads Provider code , just change the package name, the URI for your own.

      Reply
  4. Pradeep

    Thank you for a very useful post.
    I have a standalone android application (eclipse project) which cannot be added to “packages/apps” for compilation and therefore I couldn’t import “android.provider.Downloads” class in my activity class.
    Instead, I have taken the string definitions from Downloads class in my activity.

    The call to getContentResolver().insert(Uri.parse(“content://downloads/my_downloads”), values) is throwing following exception:
    10-27 21:31:01.595: ERROR/DatabaseUtils(2872): Writing exception to parcel
    10-27 21:31:01.595: ERROR/DatabaseUtils(2872): java.lang.SecurityException: Invalid value for is_public_api: null
    10-27 21:31:01.595: ERROR/DatabaseUtils(2872): at com.android.providers.downloads.DownloadProvider.enforceAllowedValues(DownloadProvider.java:686)

    10-27 21:31:18.830: ERROR/AndroidRuntime(8025): FATAL EXCEPTION: main
    10-27 21:31:18.830: ERROR/AndroidRuntime(8025): java.lang.SecurityException: Invalid value for is_public_api: null
    10-27 21:31:18.830: ERROR/AndroidRuntime(8025): at android.os.Parcel.readException(Parcel.java:1322)

    1) Is there a way I could still import Downloads class in my eclipse project?
    2) Any idea about the above exception?

    Thanks

    Reply
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