Android onRequestPermissionsResult 不适用于我的片段

Posted 2023-02-24

【中文标题】Android onRequestPermissionsResult 不适用于我的片段

【英文标题】：Android onRequestPermissionsResult not working on my fragment

【发布时间】：2017-10-01 00:22:15

【问题描述】：

在我的活动页面之一的片段中，我想获得用户的许可并在授予许可后执行一些操作，但 onRequestPermissionsResult 不起作用，并且在授予许可后我没有看到任何日志

public class FragmentAboutUs extends Fragment implements ActivityCompat.OnRequestPermissionsResultCallback 
    private Activity          activity;
    private Context           context;
    ...
    private int WRITE_EXTERNAL_STORAGE = 1;

    @Override
    public void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
    

    @Override

    public View onCreateView(LayoutInflater inflater, final ViewGroup container,
                             Bundle savedInstanceState) 
        View view = inflater.inflate(R.layout.fragment_about_us, container, false);

        activity = getActivity();
        context = getActivity().getBaseContext();

        ...

        aboutUs = SQLite.select().from(AboutUs.class).querySingle();
        if (aboutUs == null) 
            if (ActivityCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) 
                if (ActivityCompat.shouldShowRequestPermissionRationale(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE)) 
                    ActivityCompat.requestPermissions(activity, new String[]Manifest.permission.WRITE_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE);
                 else 
                    ActivityCompat.requestPermissions(activity, new String[]Manifest.permission.WRITE_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE);
                
            
        
        return view;
    

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) 
        if (requestCode == WRITE_EXTERNAL_STORAGE) 
            Log.e("permission granted"," OK");
         else 
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        
    

【问题讨论】：

你的 onRequestPermissionsResult 在哪里

【参考方案1】：

使用：

requestPermissions(permissions, PERMISSIONS_CODE);

取而代之的是你的：

ActivityCompat.requestPermissions()

您可以在此处阅读更多内容： Answer

【参考方案2】：

删除这个：

implements ActivityCompat.OnRequestPermissionsResultCallback

Fragment 可以自己处理 OnRequestPermissionsResultCallback 的 Runtime 权限：

像这样使用它：

 final int MyVersion = Build.VERSION.SDK_INT;
if (MyVersion > Build.VERSION_CODES.LOLLIPOP_MR1) 
        if (!checkIfAlreadyhavePermission()) 
            requestPermissions(new String[]Manifest.permission.WRITE_EXTERNAL_STORAGE , WRITE_EXTERNAL_STORAGE);  //request permission
         else 
            //call your method permision already granted
        
     else 
            //call your method permission not needed for this version
    


private boolean checkIfAlreadyhavePermission() 
        int result = ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE);
        return result == PackageManager.PERMISSION_GRANTED;
    

现在您可以在Fragment 内的public void onRequestPermissionsResult() 中获取权限结果

使用：

public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) 
    switch (requestCode) 
        case WRITE_EXTERNAL_STORAGE: 
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) 

                Toast.makeText(getActivity(), "permission granted", Toast.LENGTH_LONG).show();
                //call your action

             else 
                Toast.makeText(getActivity(), "permission denied", Toast.LENGTH_LONG).show();
            
            break;
        
    

【讨论】：

那么在删除implements ActivityCompat.OnRequestPermissionsResultCallback 后授予权限后如何执行自定义操作？

您可以在onRequestPermissionsResult()中调用您的操作...授予权限后--我已对其进行了编辑

requestPermissions(...) 不检查应用是否有权限？看来我必须使用checkIfAlreadyhavePermission 才能获得许可？