Attempt to invoke virtual method

日志如下

W/System.err: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.XmlResourceParser android.content.pm.ProviderInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)' on a null object reference
W/System.err:     at android.support.v4.content.FileProvider.parsePathStrategy(FileProvider.java:605)
W/System.err:     at android.support.v4.content.FileProvider.getPathStrategy(FileProvider.java:579)
W/System.err:     at android.support.v4.content.FileProvider.getUriForFile(FileProvider.java:417)

原因

AndroidManifest.xml中FileProvider配置的authorities与代码中的不同

        //Manifest
        <provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_path"/>
        </provider>
        
       //java
       String authority = activity.getPackageName() + ".fileProvider";
       uri = FileProvider.getUriForFile(activity, authority, takePictureFile);

找了好久 ${applicationId}.fileprovider和.fileProvider P一个小写一个大写，改成一致就行