Android Studio权限问题，以读取联系人列表为例

废话不多说直接上代码

package com.example.administrator.callpermission;

import android.Manifest;
import android.content.Intent;
import android.content.pm.ComponentInfo;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.NetworkRequest;
import android.net.Uri;
import android.provider.ContactsContract;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.accessibility.CaptioningManager;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private Button button;
    ArrayAdapter<String> adapter;
    List<String> contactList = new ArrayList<>();
    private ListView ListView_ReadContact;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = (Button) findViewById(R.id.Button);
        ListView_ReadContact = (ListView) findViewById(R.id.ListView_ReadContact);
        adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, contactList);
        ListView_ReadContact.setAdapter(adapter);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
//                if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE)!=
//                        PackageManager.PERMISSION_GRANTED){
//                    ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.CALL_PHONE
//                    },1);
//                }else {
//                    call();
//                }

                if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_CONTACTS) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(MainActivity.this,
                            new String[]{Manifest.permission.READ_CONTACTS}, 1);
                } else {
                    readContact();
                }
            }
        });
    }

    public void readContact() {
        Cursor cursor = null;
        try {
            cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null, null, null);
            if (cursor != null) {
                while (cursor.moveToNext()) {
                    //获取联系人姓名
                    String displayName = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
                    String Num=cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
                    contactList.add(displayName+"\n"+Num);
                }
                adapter.notifyDataSetChanged();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            if (cursor!=null){
                cursor.close();
            }
        }

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode){
            case 1:
                if (grantResults.length>0&&grantResults[0]==PackageManager.PERMISSION_GRANTED){
                    readContact();
                }else {
                    Toast.makeText(this,"未获取权限",Toast.LENGTH_SHORT).show();
                }
                break;
            default:
                break;
        }
    }
    //    @Override
//    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
//        switch (requestCode){
//            case 1:
//                if (grantResults.length>1&&grantResults[0]==PackageManager.PERMISSION_GRANTED){
//                    call();
//                }else {
//                    Toast.makeText(this,"未获得权限",Toast.LENGTH_SHORT).show();
//                }
//                break;
//            default:
//                break;
//        }
//    }
//
//    public void call(){
//        try {
//            Intent intent=new Intent(Intent.ACTION_CALL);
//            intent.setData(Uri.parse("tel:10086"));
//            startActivity(intent);
//        }catch (SecurityException e){
//            e.printStackTrace();
//        }
//
//    }
}
package com.example.administra