i've a pdf file in my app assets directory that i want open using an external app, so wrote my content provider and i'm tryng to make it work but nothing...
here is the code:
Content Provider:
package package.name;
import java.io.File;
import java.io.FileNotFoundException;
import java.net.URI;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
public class FileContentProvider extends ContentProvider {
private static final String URI_PREFIX = "content://package.name.filecontentprovider";
public static String constructUri(String url) {
Uri uri = Uri.parse(url);
return uri.isAbsolute() ? url : URI_PREFIX + url;
}
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
URI uri1 = URI.create("file:///data/data/package.name/"+uri.getPath());
File file = new File(uri1.getPath());
ParcelFileDescriptor parcel = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
return parcel;
}
@Override
public boolean onCreate() {
return true;
}
@Override
public int delete(Uri uri, String s, String[] as) {
throw new UnsupportedOperationException("Not supported by this provider");
}
@Override
public String getType(Uri uri) {
throw new UnsupportedOperationException("Not supported by this provider");
}
@Override
public Uri insert(Uri uri, ContentValues contentvalues) {
throw new UnsupportedOperationException("Not supported by this provider");
}
@Override
public Cursor query(Uri uri, String[] as, String s, String[] as1, String s1) {
throw new UnsupportedOperationException("Not supported by this provider");
}
@Override
public int update(Uri uri, ContentValues contentvalues, String s, String[] as) {
throw new UnsupportedOperationException("Not supported by this provider");
}
}
and here how i call the opening of the file:
File pdf = new File("assets/prova.pdf");
Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse("content://package.name/" + pdf));
i.setType("application/pdf");
startActivity(i);
i've added the following line in the android manifest, inside the tag:
<provider android:name=".FileContentProvider" android:authorities="package.name" />
this is the logcat output:
02-26 19:47:44.938: ERROR/AndroidRuntime(6494): Uncaught handler: thread main exiting due to uncaught exception
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tf.thinkdroid.samsung/com.tf.thinkdroid.pdf.app.PdfRenderScreen}: java.lang.NullPointerException
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread.access$2200(ActivityThread.java:119)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.os.Handler.dispatchMessage(Handler.java:99)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.os.Looper.loop(Looper.java:123)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread.main(ActivityThread.java:4363)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at java.lang.reflect.Method.invokeNative(Native Method)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at java.lang.reflect.Method.invoke(Method.java:521)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:862)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at dalvik.system.NativeStart.main(Native Method)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): Caused by: java.lang.NullPointerException
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at com.tf.thinkdroid.pdf.app.RenderScreen.onNewIntent(Unknown Source)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at com.tf.thinkdroid.pdf.app.RenderScreen.onCreate(Unknown Source)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at com.tf.thinkdroid.pdf.app.PdfRenderScreen.onCreate(Unknown Source)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
02-26 19:47:44.953: ERROR/AndroidRuntime(6494): ... 11 more
don't understand where the problem is, seem that the external application can't get the file.
thanks for any help!
I am new to android development and spent the whole day looking for the reason that my locally stored PDF could not be opened by external apps. I am glad having found this thread.
In the meantime Marco got it working and describes it here. Beware: Italian language- Google translation service might help ;-)
http://www.marcofaion.it/?p=7
http://web.archive.org/web/20111020204554/http://www.marcofaion.it/?p=7
Additional notes to his howto for beginners:
The line Marco mentions to be inserted in the Manifest.xml
<provider android:name=".FileContentProvider" android:authorities="package.name" />
should be inserted within the <application ...></application> tag.
And if you plan to have custom filenames you should exchange
InputStream is = am.open("file.pdf");
with
InputStream is = am.open(uri.getLastPathSegment());
PDF files have to be put into already existing folder assets in your project (especially not in any newly added folder res/assets or sth.)! =)