Question

我有一个Activity Main班级和XML，以及ana_sayfa（Fragment）班级和XML。

当我滑动屏幕并显示ana_sayfa时，我想将项目添加到可展开列表视图中，但我无法访问ana_sayfa Fragment到主要活动类

Main_activity类：

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    Button b1;


    private ResideMenu resideMenu;
    private Context mContext;
    private ResideMenuItem itemAnasayfa;
    private ResideMenuItem itemRastgele;
    private ResideMenuItem itemEncok;
    private ResideMenuItem itemTarifyaz;

    private ExpandableListView listView;
    private ExpandableListAdapter listAdapter;
    private List<String> listDataHeader;
    private HashMap<String,List<String>> listHash;


    private View view2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = this;
        setUpMenu();
        if (savedInstanceState == null) {

            changeFragment(new F_ana_sayfa());

        }


       /** listView=(ExpandableListView)findViewById(R.id.exp2);
        initData();
        listAdapter=new com.yeni.ExpandableListAdapter(this,listDataHeader,listHash);
        listView.setAdapter(listAdapter);
        */
    }

    private void initData() {
        listDataHeader=new ArrayList<>();
        listHash=new HashMap<>();

        listDataHeader.add("et");
        listDataHeader.add("tavuk");
        listDataHeader.add("sebze");
        listDataHeader.add("diger");

        List<String> l_et=new ArrayList<>();
        l_et.add("kemikli");
        l_et.add("kuşbaşı");

        List<String> l_tavuk=new ArrayList<>();
        l_tavuk.add("bonfile");
        l_tavuk.add("but");
        l_tavuk.add("bütün tavuk");

        List<String> l_sebze=new ArrayList<>();
        l_sebze.add("patates");
        l_sebze.add("biber");
        l_sebze.add("kabak");
        l_sebze.add("patlıcan");

        List<String> l_diger=new ArrayList<>();
        l_diger.add("tuz");
        l_diger.add("yağ");
        l_diger.add("kekik");

        listHash.put(listDataHeader.get(0),l_et);
        listHash.put(listDataHeader.get(1),l_tavuk);
        listHash.put(listDataHeader.get(2),l_sebze);
        listHash.put(listDataHeader.get(3),l_diger);
    }

    private void setUpMenu() {
        resideMenu = new ResideMenu(this);
        resideMenu.setBackground(R.drawable.menu_background);
        resideMenu.attachToActivity(this);


        resideMenu.setMenuListener(menuListener);
        resideMenu.setScaleValue(0.6f);
        //create menu items;
        itemAnasayfa = new ResideMenuItem(this, R.drawable.icon_home, "Ana Sayfa");
        itemRastgele = new ResideMenuItem(this, R.drawable.icon_profile, "Random tarif bul");
        itemEncok = new ResideMenuItem(this, R.drawable.icon_calendar, "En cok begenilenler");
        itemTarifyaz = new ResideMenuItem(this, R.drawable.icon_settings, "tarif Yaz");


        itemAnasayfa.setOnClickListener(this);
        itemRastgele.setOnClickListener(this);
        itemEncok.setOnClickListener(this);
        itemTarifyaz.setOnClickListener(this);


        resideMenu.addMenuItem(itemAnasayfa, ResideMenu.DIRECTION_LEFT);
        resideMenu.addMenuItem(itemRastgele, ResideMenu.DIRECTION_LEFT);
        resideMenu.addMenuItem(itemEncok, ResideMenu.DIRECTION_RIGHT);
        resideMenu.addMenuItem(itemTarifyaz, ResideMenu.DIRECTION_RIGHT);

        findViewById(R.id.title_bar_left_menu).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                resideMenu.openMenu(ResideMenu.DIRECTION_LEFT);
            }
        });

        findViewById(R.id.title_bar_right_menu).setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view) {

                resideMenu.openMenu(ResideMenu.DIRECTION_RIGHT);
            }
        });
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        return resideMenu.dispatchTouchEvent(ev);
    }

    @Override
    public void onClick(View view) {

        if (view == itemAnasayfa) {

            changeFragment(new F_ana_sayfa());

            listView=(ExpandableListView)findViewById(R.id.exp2);
            initData();
            listAdapter=new com.yeni.ExpandableListAdapter(this,listDataHeader,listHash);
            listView.setAdapter(listAdapter);

        } else if (view == itemRastgele) {
            changeFragment(new F_rastgele_tarif());
        } else if (view == itemEncok) {
            changeFragment(new F_encok_beg());
        } else if (view == itemTarifyaz) {
            changeFragment(new F_tarif_yaz());
        }

        resideMenu.closeMenu();
    }

    private ResideMenu.OnMenuListener menuListener = new ResideMenu.OnMenuListener() {
        @Override
        public void openMenu() {
            Toast.makeText(mContext, "Menu is aÇILDIIII!", Toast.LENGTH_SHORT).show();
        }

        @Override
        public void closeMenu() {

            Toast.makeText(mContext, "Menu is KAPANDI!", Toast.LENGTH_SHORT).show();
        }
    };

    private void changeFragment(Fragment targetFragment) {
        resideMenu.clearIgnoredViewList();
        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.main_fragment, targetFragment, "fragment")
                .setTransitionStyle(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
                .commit();
    }

    public ResideMenu getResideMenu(){
        return resideMenu;
    }
}

ana_sayfa类：

public class F_ana_sayfa extends Fragment {

    private View parentView;
    private ResideMenu resideMenu;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        parentView = inflater.inflate(R.layout.ana_sayfa, container, false);
        //setUpViews();
        return parentView;
    }

Answer 1

使用setArguments(Bundle)将数据传递到片段，并使用onCreateView()在getArguments()中检索数据。然后Fragment可以处理在列表视图中呈现数据的所有逻辑。

Answer 2

您可以使用interface来进行活动和片段之间的通信。例如，在您的片段类中，您可以添加：

public class F_ana_sayfa extends Fragment {

    ...

    SomeInterface myInterface;

    // Container activity must implement this interface
    public interface SomeInterface {
        // You can define your interface functions here
        void doSomething();
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        // This makes sure that the container activity has implemented
        // the callback interface. If not, it throws an exception
        try {
            myInterface = (SomeInterface) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString() + " must implement SomeInterface");
        }
    }

    public void someFunction(boolean someBoolean) {
        if (someBoolean) {
            // Calling the interface function
            myInterface.doSomething();
        }
    }
}

现在您的活动必须实现片段类中定义的接口。例如：

public class MainActivity extends AppCompatActivity implements F_ana_sayfa.SomeInterface {

    ...

    public void doSomething() {
        // Your code here
    }
}

有关详细信息，请访问https://developer.android.com/training/basics/fragments/communicating.html

如何访问和更改片段到主要活动

2 个答案: