<provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="com.peter.jiangbin.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_paths" />
</provider>

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <paths>
        <root-path name="rp" path="jiangbin"/>
        <files-path name="fp" path="jiangbin"/>
        <cache-path name="cp" path="jiangbin" />
        <external-path name="ep" path="jiangbin"/>
        <external-files-path name="efp" path="jiangbin" />
        <external-cache-path name="ecp" path="jiangbin" />
    </paths>
</resources>

 File file = new File(mContext.getFilesDir() + "/jiangbin", "hello.txt");
        Uri data;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            data = FileProvider.getUriForFile(mContext, "com.ysx.fileproviderserver.fileprovider", file);
        } else {
            data = Uri.fromFile(file);
        }

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | FLAG_GRANT_WRITE_URI_PERMISSION);

public class FileProvider extends ContentProvider {
    ...
    @GuardedBy("sCache")
    private static HashMap<String, PathStrategy> sCache = new HashMap<String, PathStrategy>();
    interface PathStrategy {
        public Uri getUriForFile(File file);
        public File getFileForUri(Uri uri);
    }
    static class SimplePathStrategy implements PathStrategy {
        private final String mAuthority;
        private final HashMap<String, File> mRoots = new HashMap<String, File>();
        public SimplePathStrategy(String authority) {
            mAuthority = authority;
        }
    }
    ...
}