//res目录下创建xml，设置要分享的目录,名称定义file_paths
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-path name="myFile" path ="" />
</paths>

// 注册provider
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="com.lzp.fileprovider"
android:exported="false"
// 赋予Uri权限
android:grantUriPermissions="true">

<meta-data
  android:name="android.support.FILE_PROVIDER_PATHS"
  // 设置要分享的路径
  android:resource="@xml/file_paths"/>
</provider>

Intent i = new Intent(Intent.ACTION_VIEW);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
// 判断是否是7.0
if(Build.VERSION.SDK_INT >= 24){
  // 适配android7.0 ，不能直接访问原路径
  // 需要对intent 授权
  i.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
  i.setDataAndType(FileProvider.getUriForFile(context, context.getPackageName() + ".fileProvider",new File(filePath)),"application/vnd.android.package-archive");
}
else{
  i.setDataAndType(Uri.fromFile(new File(filePath)), "application/vnd.android.package-archive");
}
context.startActivity(i);

content://com.lzp.fileprovider/myFile/xxxxx.apk