Android：选项卡式应用程序中的Toast＆amp;下一页点击选项卡式应用程序

Question

我正在尝试从我的片段中创建一个Toast。我一直在互联网上搜索几个小时，我遇到的所有东西似乎都没有用。

information.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    Toast toast = Toast.makeText(getActivity().getBaseContext(), "This information will not be published in the world wide web, but will be saved on your own device instead", Toast.LENGTH_SHORT);
                    toast.show();
                    toast.setGravity(Gravity.CENTER_VERTICAL | Gravity.CENTER_HORIZONTAL, 0, 0);
                }
            });    

＆＃39;的 getActivity ＆＃39;是红色的。在悬停时，它说：＆＃34; 无法解决方法＆＃39; getActivity（）＆＃39;＆＃34;。 如果我删除了getActivity，并且仅使用 getBaseContext（）或 getApplicationContext（），则表示无法从静态上下文中引用非静态方法< / strong>即可。任何人都可以教我如何创建这个特定的Toast吗？

我使用了Android Studio中的标准图库标签应用程序。 这是我的代码（你会在最底层找到它）：

public class ApplicationFragments extends AppCompatActivity {
        private SectionsPagerAdapter mSectionsPagerAdapter;
        private ViewPager mViewPager;

        //get widgets voor alle functies
        private static View rootView;

        //variable
        private static int section;
        //fragment1
        static ImageButton information;
        static int addOneSex;
        static int addOneWeight;
        static int addOneAge;
        static ImageView plusSex;
        static ImageView plusWeight;
        static ImageView plusAge;
        static TextView sex;
        static TextView weight;
        static TextView age;

        //fragment2
        static int addOneHour;
        static int addOneBeer;
        static int addOneWine;
        static int addOneShot;
        static ImageView plusBeers;
        static ImageView plusWines;
        static ImageView plusShots;
        static TextView plusHours;
        static TextView amountOfHours;
        static TextView amountOfBeers;
        static TextView amountOfWines;
        static TextView amountOfShots;

        //fragment3

        //all fragments
        static Button btnNext;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            //verander animatie
            overridePendingTransition(android.R.anim.slide_in_left, android.R.anim.fade_out);

            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_information);

            // Create the adapter that will return a fragment for each of the three
            // primary sections of the activity.
            mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

            // Set up the ViewPager with the sections adapter.
            mViewPager = (ViewPager) findViewById(R.id.container);
            mViewPager.setAdapter(mSectionsPagerAdapter);
        }

        public static class PlaceholderFragment extends Fragment {
            private static final String ARG_SECTION_NUMBER = "section_number";

            public static PlaceholderFragment newInstance(int sectionNumber) {
                PlaceholderFragment fragment = new PlaceholderFragment();
                Bundle args = new Bundle();
                args.putInt(ARG_SECTION_NUMBER, sectionNumber);
                fragment.setArguments(args);
                return fragment;
            }

            //bij het creëren van een tab
            @Override
            public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                     Bundle savedInstanceState) {
                rootView = inflater.inflate(R.layout.fragment_information, container, false);

                //set xml
                section = getArguments().getInt(ARG_SECTION_NUMBER);
                if (section == 1) {
                    rootView = inflater.inflate(R.layout.fragment_information, container, false);
                    GenerateFragment1();
                }
                if (section == 2) {
                    rootView = inflater.inflate(R.layout.fragment_drinks, container, false);
                    GenerateFragment2();
                }
                if (section == 3) {
                    rootView = inflater.inflate(R.layout.fragment_calculate, container, false);
                    GenerateFragment3();
                }
                return rootView;
            }
        }

        //geef de juiste pagina terug
        public class SectionsPagerAdapter extends FragmentPagerAdapter {
            public SectionsPagerAdapter(FragmentManager fm) {
                super(fm);
            }

            @Override
            public Fragment getItem(int position) {
                return PlaceholderFragment.newInstance(position + 1);
            }

            @Override
            public int getCount() {
                //hoeveelheid pagina's
                return 3;
            }

            @Override
            public CharSequence getPageTitle(int position) {
                switch (position) {
                    case 0:
                        return "SECTION 1";
                    case 1:
                        return "SECTION 2";
                    case 2:
                        return "SECTION 3";
                }
                return null;
            }
        }

        //fragment 1
        public static void GenerateFragment1(){
            information = (ImageButton) rootView.findViewById(R.id.imgBtnInfo);
            sex = (TextView) rootView.findViewById(R.id.etSex);
            weight = (TextView) rootView.findViewById(R.id.etWeight);
            age = (TextView) rootView.findViewById(R.id.etAge);
            plusSex = (ImageView) rootView.findViewById(R.id.btnSex);
            plusWeight = (ImageView) rootView.findViewById(R.id.btnWeight);
            plusAge = (ImageView) rootView.findViewById(R.id.btnAge);
            btnNext = (Button) rootView.findViewById(R.id.btnNext);

            plusSex.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    addOneSex = Integer.parseInt(sex.getText().toString());
                    addOneSex++;
                    sex.setText(Integer.toString(addOneSex));
                }
            });

            plusWeight.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    addOneWeight = Integer.parseInt(weight.getText().toString());
                    addOneWeight++;
                    weight.setText(Integer.toString(addOneWeight));
                }
            });

            plusAge.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    addOneAge = Integer.parseInt(age.getText().toString());
                    addOneAge++;
                    age.setText(Integer.toString(addOneAge));
                }
            });


            information.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    Toast toast = Toast.makeText(getActivity().getBaseContext(), "This information will not be published in the world wide web, but will be saved on your own device instead", Toast.LENGTH_SHORT);
                    toast.show();
                    toast.setGravity(Gravity.CENTER_VERTICAL | Gravity.CENTER_HORIZONTAL, 0, 0);
                }
            });

            btnNext.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    //to the next fragment
                }
            });
        }

另外，我想知道如何让应用程序转到按钮上的下一页（btnNext）。

感谢您的时间和帮助！

Answer 1

您是否有某个存储在活动中的片段列表或片段管理器？如果是这样，您可以从列表中获取下一个片段并使用片段管理器将其切换出来。关于toast getActivity（）问题：如果我理解正确，ApplicationFragments是你的主要活动？如果是这样，为什么不调用{{1}}而不是getActivity（）？