• 一行代码解决Android M新的运行时权限问题


    Android M运行时权限是个啥东西

    啥是运行时权限呢?Android M对权限管理系统进行了改版,之前我们的App需要权限,只需在manifest中申明即可,用户安装后,一切申明的权限都可来去自如的使用。但是Android M把权限管理做了加强处理,在manifest申明了,在使用到相关功能时,还需重新授权方可使用。当然,不是所有权限都需重新授权,所以就把这些需要重新授权方可使用的权限称之为运行时权限。

    运行时权限的影响

    运行时权限的好处可以让用户使用时更有主动权,不会让app随便乱来。
    但是受害最深的却是我们这些受苦受难的开发者,为何这么说呢?如果你的app的targetSdkVersion 是23也就是android 6.0的话,遇到运行时权限不去做代码处理的话,程序直接崩掉。

    所以,如果你的app没有在android 6.0上做足够的测试,请不要设置targetSdk为23,22以下就不会出现问题。
    但是,作为开发者,我们还是必须要与时俱进的不是,而且以后的主流机型也必然是android M,怎么能不去适配他/她呢?继续往下看。

    哪些是运行时权限

    要先做好适配,那就必然要先了解哪些是运行时权限。
    先看下哪些是不用特殊处理的权限,android称之为普通权限:
    参考链接:http://developer.android.com/guide/topics/security/normal-permissions.html
    As of API level 23, the following permissions are classified as PROTECTION_NORMAL:

    android.permission.ACCESS_LOCATION_EXTRA_COMMANDS
    android.permission.ACCESS_NETWORK_STATE
    android.permission.ACCESS_NOTIFICATION_POLICY
    android.permission.ACCESS_WIFI_STATE
    android.permission.ACCESS_WIMAX_STATE
    android.permission.BLUETOOTH
    android.permission.BLUETOOTH_ADMIN
    android.permission.BROADCAST_STICKY
    android.permission.CHANGE_NETWORK_STATE
    android.permission.CHANGE_WIFI_MULTICAST_STATE
    android.permission.CHANGE_WIFI_STATE
    android.permission.CHANGE_WIMAX_STATE
    android.permission.DISABLE_KEYGUARD
    android.permission.EXPAND_STATUS_BAR
    android.permission.FLASHLIGHT
    android.permission.GET_ACCOUNTS
    android.permission.GET_PACKAGE_SIZE
    android.permission.INTERNET
    android.permission.KILL_BACKGROUND_PROCESSES
    android.permission.MODIFY_AUDIO_SETTINGS
    android.permission.NFC
    android.permission.READ_SYNC_SETTINGS
    android.permission.READ_SYNC_STATS
    android.permission.RECEIVE_BOOT_COMPLETED
    android.permission.REORDER_TASKS
    android.permission.REQUEST_INSTALL_PACKAGES
    android.permission.SET_TIME_ZONE
    android.permission.SET_WALLPAPER
    android.permission.SET_WALLPAPER_HINTS
    android.permission.SUBSCRIBED_FEEDS_READ
    android.permission.TRANSMIT_IR
    android.permission.USE_FINGERPRINT
    android.permission.VIBRATE
    android.permission.WAKE_LOCK
    android.permission.WRITE_SYNC_SETTINGS
    com.android.alarm.permission.SET_ALARM
    com.android.launcher.permission.INSTALL_SHORTCUT
    com.android.launcher.permission.UNINSTALL_SHORTCUT

    再看下运行时权限,android称之为危险权限(google还对其分了组):
    参考链接:http://developer.android.com/guide/topics/security/permissions.html#normal-dangerous


    危险权限表

    同一组的任何一个权限被授权了,其他权限也自动被授权。例如,一旦WRITE_CONTACTS被授权了,app也有READ_CONTACTS和GET_ACCOUNTS了。

    ------------------------------ 关键部分来了---------------------------------------------

    代码封装

    目前对运行时权限,github上也有些代码封装库,但是都感觉用起来太麻烦,于是自己动手封装了下:
    参考代码(google写的sample):
    https://github.com/googlesamples/android-RuntimePermissions;
    http://developer.android.com/training/permissions/requesting.html

    封装代码如下:

    在BaseActivity添加如下代码:

    //**************** Android M Permission (Android 6.0权限控制代码封装) 
    *****************************************************
        private int permissionRequestCode = 88;
        private PermissionCallback permissionRunnable ;
        public interface PermissionCallback{
            void hasPermission();
            void noPermission();
        }
    
        /**
         * Android M运行时权限请求封装
         * @param permissionDes 权限描述
         * @param runnable 请求权限回调
         * @param permissions 请求的权限(数组类型),直接从Manifest中读取相应的值,比如Manifest.permission.WRITE_CONTACTS
         */
        public void performCodeWithPermission(@NonNull String permissionDes,PermissionCallback runnable,@NonNull String... permissions){
            if(permissions == null || permissions.length == 0)return;
    //        this.permissionrequestCode = requestCode;
            this.permissionRunnable = runnable;
            if((Build.VERSION.SDK_INT < Build.VERSION_CODES.M) || checkPermissionGranted(permissions)){
                if(permissionRunnable!=null){
                    permissionRunnable.hasPermission();
                    permissionRunnable = null;
                }
            }else{
                //permission has not been granted.
                requestPermission(permissionDes,permissionRequestCode,permissions);
            }
    
        }
        private boolean checkPermissionGranted(String[] permissions){
            boolean flag = true;
            for(String p:permissions){
                if(ActivityCompat.checkSelfPermission(this, p) != PackageManager.PERMISSION_GRANTED){
                    flag = false;
                    break;
                }
            }
            return flag;
        }
        private void requestPermission(String permissionDes,final int requestCode,final String[] permissions){
            if(shouldShowRequestPermissionRationale(permissions)){
                // Provide an additional rationale to the user if the permission was not granted
                // and the user would benefit from additional context for the use of the permission.
                // For example, if the request has been denied previously.
    
    //            Snackbar.make(getWindow().getDecorView(), requestName,
    //                    Snackbar.LENGTH_INDEFINITE)
    //                    .setAction(R.string.common_ok, new View.OnClickListener() {
    //                        @Override
    //                        public void onClick(View view) {
    //                            ActivityCompat.requestPermissions(BaseAppCompatActivity.this,
    //                                    permissions,
    //                                    requestCode);
    //                        }
    //                    })
    //                    .show();
                //如果用户之前拒绝过此权限,再提示一次准备授权相关权限
                new AlertDialog.Builder(this)
                        .setTitle("提示")
                        .setMessage(permissionDes)
                        .setPositiveButton(R.string.common_ok, new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                ActivityCompat.requestPermissions(BaseAppCompatActivity.this, permissions, requestCode);
                            }
                        }).show();
    
            }else{
                // Contact permissions have not been granted yet. Request them directly.
                ActivityCompat.requestPermissions(BaseAppCompatActivity.this, permissions, requestCode);
            }
        }
        private boolean shouldShowRequestPermissionRationale(String[] permissions){
            boolean flag = false;
            for(String p:permissions){
                if (ActivityCompat.shouldShowRequestPermissionRationale(this,p)){
                    flag = true;
                    break;
                }
            }
            return flag;
        }
    
        /**
         * Callback received when a permissions request has been completed.
         */
        @Override
        public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
                                               @NonNull int[] grantResults) {
            if(requestCode == permissionRequestCode){
                if(verifyPermissions(grantResults)){
                    if(permissionRunnable!=null) {
                        permissionRunnable.hasPermission();
                        permissionRunnable = null;
                    }
                }else{
                    showToast("暂无权限执行相关操作!");
                     if(permissionRunnable!=null) {
                      permissionRunnable.noPermission();
                      permissionRunnable = null;
                    }
                }
            }else{
                super.onRequestPermissionsResult(requestCode, permissions, grantResults);
            }
    
        }
        public boolean verifyPermissions(int[] grantResults) {
            // At least one result must be checked.
            if(grantResults.length < 1){
                return false;
            }
    
            // Verify that each required permission has been granted, otherwise return false.
            for (int result : grantResults) {
                if (result != PackageManager.PERMISSION_GRANTED) {
                    return false;
                }
            }
            return true;
        }
        //********************** END Android M Permission ****************************************

    Tips:

    1)BaseActivity要继承AppCompatActivity
    2)support包使用尽量新的,我使用的是compile 'com.android.support:appcompat-v7:23.0.1' 以防里面的ActivityCompat找不到相关类或方法。
    3)如果在Fragment中使用,直接在自己的BaseFragment写个方法调用此Activity的方法即可。

    /**
         * Android M运行时权限请求封装
         * @param permissionDes 权限描述
         * @param runnable 请求权限回调
         * @param permissions 请求的权限(数组类型),直接从Manifest中读取相应的值,比如Manifest.permission.WRITE_CONTACTS
         */
        public void performCodeWithPermission(@NonNull String permissionDes,BaseAppCompatActivity.PermissionCallback runnable,@NonNull String... permissions){
            if(getActivity()!=null && getActivity() instanceof BaseAppCompatActivity){
                ((BaseAppCompatActivity) getActivity()).performCodeWithPermission(permissionDes,runnable,permissions);
            }
        }

    一句代码使用:

    比如,我们要请求相机:

    performCodeWithPermission("XX App请求访问相机权限",new BaseAppCompatActivity.PermissionCallback() {
                            @Override
                            public void hasPermission() {
                                //执行打开相机相关代码
                            }
                            @Override
                            public void noPermission() {
                            }
                        }, Manifest.permission.CAMERA, Manifest.permission.READ_EXTERNAL_STORAGE,Manifest.permission.WRITE_EXTERNAL_STORAGE);

    写在最后

    • 如果读者还是没有看过文章开头推荐的文章,建议先看一遍,有些知识和出现问题的场景此文没有细说,看完后对运行时权限会有更好的理解。
    • 另外,如果本文有描述不对之处,还望大家多多指正,多谢!

    ===20160509更新========

    checkSelfPermission检测权限失效问题

    要改成如下的检测方案:
    参考:http://stackoverflow.com/questions/33407250/checkselfpermission-method-is-not-working-in-targetsdkversion-22

    public boolean selfPermissionGranted(String permission) {
            // For Android < Android M, self permissions are always granted.
            boolean result = true;
    
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    
                if (targetSdkVersion >= Build.VERSION_CODES.M) {
                    // targetSdkVersion >= Android M, we can
                    // use Context#checkSelfPermission
                    result = context.checkSelfPermission(permission)
                            == PackageManager.PERMISSION_GRANTED;
                } else {
                    // targetSdkVersion < Android M, we have to use PermissionChecker
                    result = PermissionChecker.checkSelfPermission(context, permission)
                            == PermissionChecker.PERMISSION_GRANTED;
                }
            }
    
            return result;
        }

    获取target sdk的方法如下:

    try {
            final PackageInfo info = context.getPackageManager().getPackageInfo(
                    context.getPackageName(), 0);
            targetSdkVersion = info.applicationInfo.targetSdkVersion;
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }

    官方解决方案 EasyPermissions

    google自己出了一个解决方案,在github上叫easypermissions。
    链接为:https://github.com/googlesamples/easypermissions



    文/Adley(简书作者)
    原文链接:http://www.jianshu.com/p/d3a998ec04ad
    著作权归作者所有,转载请联系作者获得授权,并标注“简书作者”。
  • 相关阅读:
    JS调试debug
    避免使用 JS 特性 with(obj){}
    bit Byte KB MB GB TB 单位换算
    C语言中连接器介绍
    [bzoj3600]没有人的算术
    [bzoj4373]算术天才⑨与等差数列
    [bzoj4151][AMPPZ2014]The Cave
    [bzoj4906][BeiJing2017]喷式水战改
    [bzoj4908][BeiJing2017]开车
    [Codeforces Round#417 Div.2]
  • 原文地址:https://www.cnblogs.com/Free-Thinker/p/5667068.html
Copyright © 2020-2023  润新知