内容提供者概述

内容提供者（ContentProvider）是Android系统四大组件之一，它是不同应用程序之间进行数据共享的标准API，通过ContentResolver类可以访问ContentProvider中共享的数据。

获取相应操作的Uri，Uri.parse()方法是将字符串转化成Uri对象。

Uri uri= Uri.parse("content://sms/");

获取ContentResolver对象

ContentResolver contentResolver = getContentResolver();

通过ContentResolver对象查询数据

Cursor cursor = contentResolver .query(uri,new String[]{
        "_id","address","body"},null,null,null);

/data/data/com.google.android.apps.messaging/databases # sqlite3 bugle_db

新建一个ContentResolver程序，拿到手机短信内容

参考代码：

package com.example.myapplication;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;

import android.Manifest;
import android.content.ContentResolver;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void click(View view) {
        ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.READ_SMS},1);
    }
    private  void getSms(){
        Uri uri= Uri.parse("content://sms/");
        ContentResolver contentResolver = getContentResolver();
        Cursor cursor = contentResolver .query(uri,new String[]{
                "_id","address","body"},null,null,null);
        if(cursor!=null &&cursor.getCount()>0){
            while(cursor.moveToNext()){
                int _id =cursor.getInt(0);
                String address =cursor.getString(1);
                String body= cursor.getString(2);
                Toast.makeText(MainActivity.this,body, Toast.LENGTH_SHORT).show();
            }
        }
}
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode==1){
            for(int i=0;i<permissions.length;i++){
                if(grantResults[i]== PackageManager.PERMISSION_GRANTED){

                    Toast.makeText(this, "获取权限成功", Toast.LENGTH_SHORT).show();
                    getSms();
                }else{
                    Toast.makeText(this, "权限"+permissions[i]+"申请失败，不能读取系统短信", Toast.LENGTH_SHORT).show();
                }
            }

        }
    }
}