Question

如果他/她第一次拒绝，我想在这种情况下向用户请求许可。我已设置权限，但即使按拒绝选项，我的应用也会运行。我有一个代码，应该做我想做的事情，但当我点击Alt + Enter时，我得到解决符号 Snackbar 它创建了另一个活动并保持 -make 和 -permision_available_camera 会出现红色错误。

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

        if (requestCode == REQUEST_CAMERA) {
            // BEGIN_INCLUDE(permission_result)
            // Received permission result for camera permission.
            Log.i(TAG, "Received response for Camera permission request.");

            // Check if the only required permission has been granted
            if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // Camera permission has been granted, preview can be displayed
                Log.i(TAG, "CAMERA permission has now been granted. Showing preview.");
                Snackbar.make(mLayout, R.string.permision_available_camera,
                        Snackbar.LENGTH_SHORT).show();
            } else {
                Log.i(TAG, "CAMERA permission was NOT granted.");
                Snackbar.make(mLayout, R.string.permissions_not_granted,
                        Snackbar.LENGTH_SHORT).show();

            }

Answer 1

@Arjun Thakun这是一种管理再次询问权限概念的方法，并处理用户在询问权限时可以回答的所有方式

void loopOver( std::vector<Particle*> const vec ){
for (auto i = vec.begin(); i != vec.end(); i++){
    std::cout << "avem " << (*i)->getXPos() << " " << (*i)->getYPos() << std::endl;
}
}

Answer 2

尝试一下

基本上，这里我们试图从外部存储中读取内容。为此，我们必须询问用户运行时权限。如果用户允许，可以，但是如果用户拒绝该许可，它将显示第二个对话框/消息框，直到用户接受该许可为止

寻求许可

如果用户拒绝，则在用户启动应用程序时将显示“需要权限”对话框

如果用户按下“确定”按钮，它将再次询问权限。

 public class MainActivity extends AppCompatActivity {

        public static int REQUEST_PERMISSION=1;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            permission_fn();


        }

        private  void requestStoragePermission()
        {
            if(ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.READ_EXTERNAL_STORAGE))
            {
                new AlertDialog.Builder(this)
                        .setTitle("Permission Needed")
                        .setMessage("Permission is needed to access files from your device...")
                        .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},REQUEST_PERMISSION);
                            }
                        })
                        .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.dismiss();
                            }
                        }).create().show();
            }
            else
            {
                ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},REQUEST_PERMISSION);
            }
        }

        private void permission_fn()
        {
            if(ContextCompat.checkSelfPermission(MainActivity.this,Manifest.permission.READ_EXTERNAL_STORAGE)== PackageManager.PERMISSION_GRANTED)
            {
                if(ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE))
                {

                }
                else
                {
                    ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},REQUEST_PERMISSION);
                }
            }
            else {

                requestStoragePermission();

            }
        }

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

                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    Toast.makeText(this, "Thanks for enabling the permission", Toast.LENGTH_SHORT).show();

                    //do something permission is allowed here....

                } else {

                    Toast.makeText(this, "Please allow the Permission", Toast.LENGTH_SHORT).show();


                }
            }

        }


        }

在AndroidManifest.xml文件中添加用户权限

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

如果用户第一次拒绝，如何再次请求权限（RunTime）

2 个答案: