<uses-permission android:name="android.permission.READ_CONTACTS"/>

package com.xxx.xxx;

import android.Manifest;

import android.app.Activity;

import android.content.pm.PackageManager;

import android.os.Bundle;

import android.widget.Toast;

public class MainActivity extends Activity {

    private static final int MY_PERMISSIONS_REQUEST_READ_CONTACTS = 0;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        // 检查是否有权限

        if (checkSelfPermission(Manifest.permission.READ_CONTACTS) != PackageManager.PERMISSION_GRANTED) {

            if (shouldShowRequestPermissionRationale(Manifest.permission.READ_CONTACTS)) {

                // 向用户说明为什么需要该权限的提示

                Toast.makeText(this, "Apply Reason:申请原因。。。", Toast.LENGTH_LONG).show();

            }

            // 请求权限，系统会显示一个获取权限的提示对话框，当前应用不能配置和修改这个对话框

            requestPermissions(new String[] { Manifest.permission.READ_CONTACTS },

                    MY_PERMISSIONS_REQUEST_READ_CONTACTS);

            return;

        }

    }

    @Override

    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {

        switch (requestCode) {

        case MY_PERMISSIONS_REQUEST_READ_CONTACTS: {

            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // 申请成功

                Toast.makeText(this, "Apply Perssion Successfully", Toast.LENGTH_SHORT).show();

            } else {

                // 申请失败

                Toast.makeText(this, "Apply Perssion Failed", Toast.LENGTH_SHORT).show();

                // 当用户选择拒绝并勾选记住选择存在问题

                // 1、不重新申请的话，会永远获取不到权限

                // 2、此处代码，重新申请会陷入死循环，一直提示申请失败，需要调整处理方式

            }

            return;

        }

        }

    }

}

ContextCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)

ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)