Android development: When you get short message content, you can get short message content, but you can't get the number and sender?

Google above android4.4 has improved the security of users. If you want to get the sender of the short message, you have to get the mobile phone number, which is the mobile phone number. The operator wrote the card information directly into the card, and now the operator doesn't continue to write it. Some mobile phone card information obtained through imsi cannot be obtained, and some can be successful! You can try to get users to send you text messages and ask for their mobile phone numbers.