Android N 7.0 上安装apk问题

android.os.FileUriExposedException: file:///storage/emulated/0/trgis/1511427343635.apk exposed beyond app through Intent.getData()

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

<?xml version="1.0" encoding="utf-8"?>
<resources>
<paths>
    <external-path
        name="files_root"
        path="" />
</paths>
</resources>

Intent intent = new Intent(Intent.ACTION_VIEW);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
   /* Android N 写法*/
   intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
   Uri contentUri = FileProvider.getUriForFile(MainActivity.this, BuildConfig.APPLICATION_ID + ".fileProvider", new File("apk地址"));
   intent.setDataAndType(contentUri, "application/vnd.android.package-archive");
} else {
   /* Android N之前的老版本写法*/
   intent.setDataAndType(Uri.fromFile(new File("apk地址")), "application/vnd.android.package-archive");
   intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
}
startActivity(intent);