Xamarin Forms File Provider not set

The readme says:

If your application targets Android N (API 24) or newer, you must use version 2.6.0+.

You must also add a few additional configuration files to adhere to the new strict mode:

1.) Add the following to your AndroidManifest.xml inside the tags:

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

YOUR_APP_PACKAGE_NAME must be set to your app package name!

2.) Add a new folder called xml into your Resources folder and add a new XML file called file_paths.xml

Add the following code:

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-files-path name="my_images" path="Pictures" />
    <external-files-path name="my_movies" path="Movies" />
</paths>

YOUR_APP_PACKAGE_NAME must be set to your app package name!

You can read more at: https://developer.android.com/training/camera/photobasics.html

In my case it was because I had put the FileProvider in the wrong place in the AndroidManifest.xml file. It needed to be inside the <Application> tags.

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.myapp.app1" android:installLocation="auto">
        <uses-sdk android:minSdkVersion="22" android:targetSdkVersion="27" />
        <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
        <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
        <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
        <uses-permission android:name="android.permission.ACCESS_SURFACE_FLINGER" />
        <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
        <uses-permission android:name="android.permission.BROADCAST_WAP_PUSH" />
        <uses-permission android:name="android.permission.CAMERA" />
        <uses-permission android:name="android.permission.INTERNET" />
        <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
        <uses-permission android:name="android.permission.RECEIVE_WAP_PUSH" />
        <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
        <uses-permission android:name="android.permission.WRITE_SETTINGS" />
        <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
        <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
        <application android:label="app1.Android">
            <meta-data android:name="com.google.android.maps.v2.API_KEY" android:value="AIzaSyCZF1O9_7-MXlxYfAEIxBQkr-dR8RiwiYE" />

            <!-- ADD FILE PROVIDER HERE -->
            <provider android:name="android.support.v4.content.FileProvider"
                  android:authorities="com.myapp.app1.fileprovider"
                  android:exported="false"
                  android:grantUriPermissions="true">
              <meta-data android:name="android.support.FILE_PROVIDER_PATHS"
              android:resource="@xml/file_paths"></meta-data>
            </provider>

        </application>
    </manifest>