我在Android m中写了一个权限请求的简写，这段代码还处理了对旧Android版本的向后兼容性。

所有丑陋的代码都被提取到一个片段中，该片段将自己附加到请求权限的活动上。PermissionRequestManager的使用方法如下:

new PermissionRequestManager()
        // We need a AppCompatActivity here, if you are not using support libraries you will have to slightly change 
        // the PermissionReuqestManager class
        .withActivity(this)

        // List all permissions you need
        .withPermissions(android.Manifest.permission.CALL_PHONE, android.Manifest.permission.READ_CALENDAR)

        // This Runnable is called whenever the request was successfull
        .withSuccessHandler(new Runnable() {
            @Override
            public void run() {
                // Do something with your permissions!
                // This is called after the user has granted all 
                // permissions, we are one a older platform where 
                // the user does not need to grant permissions 
                // manually, or all permissions are already granted

            }
        })

        // Optional, called when the user did not grant all permissions
        .withFailureHandler(new Runnable() {
            @Override
            public void run() {
                // This is called if the user has rejected one or all of the requested permissions
                L.e(this.getClass().getSimpleName(), "Unable to request permission");

            }
        })

        // After calling this, the user is prompted to grant the rights
        .request();

来看看:https://gist.github.com/crysxd/385b57d74045a8bd67c4110c34ab74aa

你可以在onRequestPermissionsResult()中检查shouldShowRequestPermissionRationale()。

https://youtu.be/C8lUdPVSzDk?t=2m23s

在onRequestPermissionsResult()中检查权限是否被授予。如果不是，检查shouldShowRequestPermissionRationale()。

如果此方法返回true，则说明为什么需要此特定权限。然后根据用户的选择再次请求permissions()。 如果它返回false，则显示一个错误消息，权限未授予，应用程序不能继续前进或特定功能被禁用。

下面是示例代码。

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    switch (requestCode) {
        case STORAGE_PERMISSION_REQUEST:
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // permission was granted :)
                downloadFile();
            } else {
                // permission was not granted
                if (getActivity() == null) {
                    return;
                }
                if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                    showStoragePermissionRationale();
                } else {
                    Snackbar snackbar = Snackbar.make(getView(), getResources().getString(R.string.message_no_storage_permission_snackbar), Snackbar.LENGTH_LONG);
                    snackbar.setAction(getResources().getString(R.string.settings), new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            if (getActivity() == null) {
                                return;
                            }
                            Intent intent = new Intent();
                            intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                            Uri uri = Uri.fromParts("package", getActivity().getPackageName(), null);
                            intent.setData(uri);
                            OrderDetailFragment.this.startActivity(intent);
                        }
                    });
                    snackbar.show();
                }
            }
            break;
    }
}

显然，谷歌maps对位置许可正是这样做的。

相反，你会收到回调onRequestPermissionsResult()作为PERMISSION_DENIED当你再次请求权限时，而落在shouldShowRequestPermissionRationale()的错误条件下

来自Android文档:

When the system asks the user to grant a permission, the user has the option of telling the system not to ask for that permission again. In that case, any time an app uses requestPermissions() to ask for that permission again, the system immediately denies the request. The system calls your onRequestPermissionsResult() callback method and passes PERMISSION_DENIED, the same way it would if the user had explicitly rejected your request again. This means that when you call requestPermissions(), you cannot assume that any direct interaction with the user has taken place.

试试这个简单的权限库。它将在3个简单的步骤中处理与权限相关的所有操作。这节省了我的时间。您可以在15分钟内完成所有权限相关的工作。

它可以处理拒绝，它可以处理永不再请求，它可以调用应用程序设置的权限，它可以给出一个Rational消息，它可以给出一个拒绝消息，它可以给出一个接受的权限列表，它可以给出一个拒绝的权限列表，等等。

https://github.com/ParkSangGwon/TedPermission

步骤1:添加依赖项

dependencies {
     compile 'gun0912.ted:tedpermission:2.1.1'
     //check the above link for latest libraries
}

步骤2:征求许可

TedPermission.with(this)
    .setPermissionListener(permissionlistener)
    .setDeniedMessage("If you reject permission,you can not use this service\n\nPlease turn on permissions at [Setting] > [Permission]")
    .setPermissions(Manifest.permission.READ_CONTACTS, Manifest.permission.ACCESS_FINE_LOCATION)
    .check();

步骤3:处理权限响应

PermissionListener permissionlistener = new PermissionListener() {
    @Override
    public void onPermissionGranted() {
        Toast.makeText(MainActivity.this, "Permission Granted", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onPermissionDenied(ArrayList<String> deniedPermissions) {
        Toast.makeText(MainActivity.this, "Permission Denied\n" + deniedPermissions.toString(), Toast.LENGTH_SHORT).show();
    }
};

请不要为这个解决办法向我扔石头。

这是可行的，但有点“俗气”。

当调用requestPermissions时，注册当前时间。

        mAskedPermissionTime = System.currentTimeMillis();

然后在onRequestPermissionsResult中

如果结果不允许，请再次检查时间。

 if (System.currentTimeMillis() - mAskedPermissionTime < 100)

由于用户不可能那么快地点击拒绝按钮，我们知道他选择了“永不再问”，因为回调是即时的。

使用风险自负。

你可以使用

shouldShowRequestPermissionRationale()

内部

onRequestPermissionsResult()

请看下面的例子:

当用户点击按钮时检查是否有权限:

@Override
public void onClick(View v) {
    if (v.getId() == R.id.appCompatBtn_changeProfileCoverPhoto) {
        if (Build.VERSION.SDK_INT < 23) { // API < 23 don't need to ask permission
            navigateTo(MainActivity.class); // Navigate to activity to change photos
        } else {
            if (ContextCompat.checkSelfPermission(SettingsActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    != PackageManager.PERMISSION_GRANTED) {
                // Permission is not granted yet. Ask for permission...
                requestWriteExternalPermission();
            } else {
                // Permission is already granted, good to go :)
                navigateTo(MainActivity.class);
            }
        } 
    }
}

当用户回答权限对话框时，我们将进入onRequestPermissionResult:

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);

    if (requestCode == WRITE_EXTERNAL_PERMISSION_REQUEST_CODE) {
        // Case 1. Permission is granted.  
        if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {  
            if (ContextCompat.checkSelfPermission(SettingsActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    == PackageManager.PERMISSION_GRANTED) {
                // Before navigating, I still check one more time the permission for good practice.
                navigateTo(MainActivity.class);
            }
        } else { // Case 2. Permission was refused
            if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                // Case 2.1. shouldShowRequest... returns true because the
                // permission was denied before. If it is the first time the app is running we will 
                // end up in this part of the code. Because he need to deny at least once to get 
                // to onRequestPermissionsResult. 
                Snackbar snackbar = Snackbar.make(findViewById(R.id.relLayout_container), R.string.you_must_verify_permissions_to_send_media, Snackbar.LENGTH_LONG);
                snackbar.setAction("VERIFY", new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        ActivityCompat.requestPermissions(SettingsActivity.this
                                , new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}
                                , WRITE_EXTERNAL_PERMISSION_REQUEST_CODE);
                    }
                });
                snackbar.show();
            } else {
                // Case 2.2. Permission was already denied and the user checked "Never ask again". 
                // Navigate user to settings if he choose to allow this time.
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setMessage(R.string.instructions_to_turn_on_storage_permission)
                        .setPositiveButton(getString(R.string.settings), new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                Intent settingsIntent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                                Uri uri = Uri.fromParts("package", getPackageName(), null);
                                settingsIntent.setData(uri);
                                startActivityForResult(settingsIntent, 7);
                            }
                        })
                        .setNegativeButton(getString(R.string.not_now), null);
                Dialog dialog = builder.create();
                dialog.show();
            }
        }
    }

}