问题
I have an app that is using ActiveAndroid and it's been working fine. However; now when I try to save a model to the database I'm getting a SecurityException.
The stack is:
Error saving model java.lang.SecurityException: Failed to find provider null for user 0; expected to find a valid ContentProvider for this authority
at android.os.Parcel.readException(Parcel.java:1942)
at android.os.Parcel.readException(Parcel.java:1888)
at android.content.IContentService$Stub$Proxy.notifyChange(IContentService.java:801)
at android.content.ContentResolver.notifyChange(ContentResolver.java:2046)
at android.content.ContentResolver.notifyChange(ContentResolver.java:1997)
at android.content.ContentResolver.notifyChange(ContentResolver.java:1967)
at com.activeandroid.Model.save(Model.java:162)
[.... local stack removed]
Has anyone else experienced this? Do we need to specify the Content Provider in the AndroidManifest.xml?
Sorry but I do not have an isolated example of this yet. I will work to put something together.
Thanks in advance
回答1:
As pointed out by @GeigerGeek security changes on Android 26 and above require you to specify the content provider in your manifest.
For ActiveAndroid you can add the below to your Manifest and change your package name.
<provider
android:name="com.activeandroid.content.ContentProvider"
android:authorities="<your.package.name>"
android:enabled="true"
android:exported="false">
</provider>
If using flavours on your build process you can use below instead:
android:authorities="${applicationId}"
Using ${applicationId} will help in flavor based project structure where application package may be different for each flavors.
For more solutions or info this was taken from here.
回答2:
For hot fix, set your
compileSdkVersion 25
targetSDKVersion 25
and you will ignore android O features. It will save your day!
important for hot fix:
But this solution will be invalid.
August 2018: New apps required to target API level 26 (Android 8.0) or higher. November 2018: Updates to existing apps required to target API level 26 or higher. 2019 onwards: Each year the targetSdkVersion requirement will advance. Within one year following each Android dessert release, new apps and app updates will need to target the corresponding API level or higher.
Another ways, you can fix with ActiveAndroid but It is deprecated now. You can try or you can try ReActiveAndroid
with ActiveAndroid, visit https://github.com/pardom/ActiveAndroid/issues/536#issuecomment-344470558
When project have defined model classes in java source code through addModelClasses configuration method application will still be crashing cause model classes wont be loaded through that configuration. In that situation You need to move model definition to the AndroidManifest.xml file.
AndroidManifest.xml
<provider
android:name=".content.DatabaseContentProvider"
android:authorities="your package name"
android:exported="false" />
DatabaseContentProvider.java
...
import com.activeandroid.content.ContentProvider;
...
public class DatabaseContentProvider extends ContentProvider {
@Override
protected Configuration getConfiguration() {
Configuration.Builder builder = new Configuration.Builder(getContext());
builder.addModelClass(SomeModel.class);
builder.addModelClass(OtherModel.class);
return builder.create();
}}
If you are doing something with FileProvider, don't miss to change package name
Uri contentUri = FileProvider.getUriForFile(mContext,
"your package name", new File(mImageFilePath));
回答3:
Android O apparently requires the use of a custom ContentProvider for database usage, even if you do not intend to share your data with other applications.
https://developer.android.com/about/versions/oreo/android-8.0-changes.html
Your custom class must be defined in a provider tag within your application tag in AndroidManifest.xml. If applicable, set exported=false to protect your data from external usage.
<provider android:name=".MyContentProvider"
android:exported="false"
android:authorities="com.your_app_path.MyContentProvider"/>
For me the problem arose because I was calling notifyChange from the contentResolver. I ended up not needing this, so I was able to avoid implementation a ContentProvider.
回答4:
if your package is different from your applicationId then you should use the applicationId
<provider
android:name="com.activeandroid.content.ContentProvider"
android:authorities="${applicationId}"
android:exported="false" />
回答5:
Maybe because of your uri is null when you use notifyChange, https://developer.android.com/about/versions/oreo/android-8.0-changes.html#ccn
Android O will add check for provider:
311 .checkContentProviderAccess(uri.getAuthority(), userHandle);
312 if (msg != null) {
313 if (targetSdkVersion >= Build.VERSION_CODES.O) {
314 throw new **SecurityException**(msg);
315 } else {
回答6:
I was redirected to this question when I was searching for the same problem. However, this specific question concerns to an specific library implementation. To overcome this error due to the changes which are newly introduced in Android O, we have to provide the specific authority to the ContentProvider by adding the following in the AndroidManifest.xml file under application tag.
<provider
android:name=".DatabaseContentProvider"
android:authorities="com.yourpackage.name"
android:exported="false" />
And you need to have a ContentProvider class like the following.
public class DatabaseContentProvider extends ContentProvider {
@Nullable
@Override
public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {
return null;
}
@Nullable
@Override
public Cursor query(@NonNull Uri uri,
@Nullable String[] projection,
@Nullable String selection,
@Nullable String[] selectionArgs,
@Nullable String sortOrder) {
return null;
}
@Override
public boolean onCreate() {
return true;
}
@Override
public int update(@NonNull Uri uri, @Nullable ContentValues values,
@Nullable String selection, @Nullable String[] selectionArgs) {
return 0;
}
@Override
public int delete(@NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {
return 0;
}
@Nullable
@Override
public String getType(@NonNull Uri uri) {
return null;
}
}
回答7:
There are two simple steps.
You need to have the provider specified in your
AndroidManifest.xmlunder yourapplicationtag like the following.<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round" android:theme="@style/AppTheme"> <activity android:name=".activity.MainActivity" android:label="@string/app_name" android:theme="@style/AppTheme.NoActionBar"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <provider android:name=".util.DatabaseContentProvider" android:authorities="com.your.application.package.name" android:exported="false" /> </application>And you need to have the java class which specifies the provider stated in the manifest. In my case, I had the provider file in the
utilpackage.package com.your.application.package.name.util; import android.content.ContentProvider; import android.content.ContentValues; import android.database.Cursor; import android.net.Uri; import android.support.annotation.NonNull; import android.support.annotation.Nullable; public class DatabaseContentProvider extends ContentProvider { @Nullable @Override public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) { return null; } @Nullable @Override public Cursor query(@NonNull Uri uri, @Nullable String[] projection, @Nullable String selection, @Nullable String[] selectionArgs, @Nullable String sortOrder) { return null; } @Override public boolean onCreate() { return true; } @Override public int update(@NonNull Uri uri, @Nullable ContentValues values, @Nullable String selection, @Nullable String[] selectionArgs) { return 0; } @Override public int delete(@NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) { return 0; } @Nullable @Override public String getType(@NonNull Uri uri) { return null; } }
That's it. You are good to go.
Here is a complete working code for SQLite read/write/update operation in Github. Hope that helps!
回答8:
I had the exact same problem with active android on Android O. Turns out that one of the methods in my custom ContentProvider returned a Uri, some times it would return null and this was causing the issue. So I added the @Nullable annotation to the method as shown below which fixed the problem.
@Nullable
@Override
public Uri insert(Uri uri, ContentValues contentValues) {..}
回答9:
Edit Manifest and add this provider tag node in side application node.
<application ....>
<provider android:name="com.activeandroid.content.ContentProvider"
android:exported="false"
android:enabled="true"
android:authorities="here will be package name of your app"/>
.....
</application>
I use this and it fixed my error. Click here for demo.
回答10:
i know there already good answer is there, but i dont understand how to best way to fix this bug and read this post Fixing SecurityException requiring a valid ContentProvider on Android 8, it very helpful to fix my bug i hope its helpful for other, Cheers!!!
来源：https://stackoverflow.com/questions/45925380/securityexception-failed-to-find-provider-null-for-user-0-on-activeandroid-on