ViewPage中替换片段的java问题

Question

我正在尝试替换ViewPager中第二个上的第一个片段。我有一个小问题，因为在替换之后，我仍然首先在背景片段中看到，并且他们首先从片段开始工作listner。我做错了什么？我替换了第一个片段视图，但它不起作用。在另一个项目中，我做了一些类似的事情，效果很好

public class FirstFragment extends BaseFragment {

private RecyclerView pathwaysRecyclerView;


@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_pathways, container, false);
    initializeViews(view);
    initRecyclerView();
    return view;
}

private void initializeViews(View view) {
    pathwaysRecyclerView = view.findViewById(R.id.pathways_recyclerview);

}

private void initRecyclerView(){
    pathwaysRecyclerView.setLayoutManager(new GridLayoutManager(requireContext(), 2));
    PathwaysAdapter adapter = new PathwaysAdapter(new OnPathwayClickListner(),requireContext());
    pathwaysRecyclerView.setAdapter(adapter);
}

private class OnPathwayClickListner implements View.OnClickListener {

    @Override
    public void onClick(View view) {
        navigateToSecondFragment();
    }
}

private void navigateToSecondFragment(){
    Fragment fragment = new SecondFragment();


    getActivity().getSupportFragmentManager().beginTransaction()
            .replace(R.id.fragment_pathways_view, fragment)
            .addToBackStack(null)
            .commit();
}


@Override
public void updateView() {

}

}

首先是你。xml

<RelativeLayout xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
    xmlns:app="http://schemas.安卓.com/apk/res-auto"
    安卓:layout_width="match_parent"
    安卓:layout_height="match_parent"
    安卓:id="@+id/fragment_pathways_view">
    <LinearLayout
        安卓:layout_width="match_parent"
        安卓:layout_height="match_parent"
        安卓:background="@color/greyAccent"
        安卓:orientation="vertical">
        <LinearLayout
            安卓:id="@+id/ebpHeader"
            安卓:layout_width="match_parent"
            安卓:layout_height="wrap_content"
            安卓:background="@color/greyAccent"
            安卓:orientation="vertical" >
            <TextView
                安卓:id="@+id/pathways_name_tv"
                安卓:layout_width="wrap_content"
                安卓:layout_height="wrap_content"
                安卓:text="@string/list_of_all_paths"
                安卓:layout_margin="15sp"
                app:fontFamily="sans-serif-light"
                安卓:textSize="25sp"
                安卓:textStyle="bold"
                />

            <TextView
                安卓:layout_width="match_parent"
                安卓:layout_height="wrap_content"
                安卓:layout_marginTop="@dimen/vertical_margin"
                安卓:layout_marginStart="@dimen/vertical_margin"
                安卓:layout_marginEnd="@dimen/vertical_margin"
                安卓:layout_marginBottom="@dimen/beetwen_content_line_margin"
                安卓:textSize="@dimen/textSizeMedium"
                安卓:text="@string/list_of_all_paths_description"/>


        </LinearLayout>

    <LinearLayout
        安卓:layout_width="match_parent"
        安卓:layout_height="match_parent"
        安卓:orientation="vertical"
        安卓:background="@drawable/evaluation_background">

        <安卓x.recyclerview.widget.RecyclerView
            安卓:id="@+id/pathways_recyclerview"
            安卓:layout_marginTop="@dimen/beetwen_content_line_margin"
            安卓:layout_marginStart="@dimen/vertical_margin"
            安卓:layout_marginEnd="@dimen/vertical_margin"
            安卓:layout_width="match_parent"
            安卓:layout_height="match_parent" />
    </LinearLayout>
    </LinearLayout>


</RelativeLayout>

第二段

public class SecondFragment extends BaseFragment {



@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_path, container, false);

    return view;
}
}

碎片秒。xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
    xmlns:app="http://schemas.安卓.com/apk/res-auto"
    安卓:layout_width="match_parent"
    安卓:layout_height="match_parent"
    安卓:background="@color/mainAppBackgroundColor">

    <LinearLayout
        安卓:layout_width="match_parent"
        安卓:layout_height="match_parent"
        安卓:background="@color/mainAppBackgroundColor"
        安卓:orientation="vertical">
        <TextView
                安卓:id="@+id/path_name_tv"
                安卓:layout_width="wrap_content"
                安卓:layout_height="wrap_content"
                安卓:layout_margin="15sp"
                app:fontFamily="sans-serif-light"
                安卓:textSize="25sp"
                安卓:textStyle="bold"
                />



        <TextView
            安卓:layout_width="wrap_content"
            安卓:layout_height="wrap_content"
            安卓:text="@string/list_of_skills"
            安卓:layout_marginTop="15sp"
            安卓:layout_marginStart="15sp"
            安卓:layout_marginEnd="15sp"
            app:fontFamily="sans-serif-light"
            安卓:textSize="18sp"
            安卓:textStyle="bold"
            />

        <安卓x.recyclerview.widget.RecyclerView
            安卓:layout_width="match_parent"
            安卓:layout_height="match_parent"
            安卓:layout_marginStart="@dimen/vertical_margin"
            安卓:layout_marginTop="5sp"
            安卓:layout_marginEnd="@dimen/vertical_margin" />
    </LinearLayout>


</RelativeLayout>

浏览页面：

<com.habitcoach.安卓.activity.util.NonSwipeableViewPager
        安卓:id="@+id/hsFragmentsContainer"
        安卓:layout_width="match_parent"
        安卓:layout_height="match_parent"
        安卓:layout_alignParentStart="true"
        安卓:layout_alignParentTop="true"
        安卓:orientation="vertical"
        安卓:paddingBottom="50dp"
        安卓:layout_alignParentLeft="true" />

页面适配器：

class MainViewViewPageAdapter extends FragmentStatePagerAdapter {

MainViewViewPageAdapter(FragmentManager fm) {
    super(fm);
}

@Override
public int getItemPosition(Object object) {
    BaseFragment f = (BaseFragment) object;
    if (f != null) {
        f.updateView();
    }
    return super.getItemPosition(object);
}

@Override
public Fragment getItem(int position) {
    Fragment f = null;
    switch (position) {
        case 0:
            f = new OneFragment();
            break;
        case 1:
            f = new TwoFragment();
            break;
        case 2:
            f = new ThreeeFragment();
            break;
        case 3:
            f = new FourFragment();
            break;
    }
    return f;
}

@Override
public int getCount() {
    return 4;
}
}

Answer 1

我修改了你的代码。检查下面的解决方案

主要活动。爪哇

public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    ViewPager viewPager = (ViewPager) findViewById(R.id.hsFragmentsContainer);
    viewPager.setAdapter(new MainViewViewPageAdapter(getSupportFragmentManager()));
}}

主要活动。xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<android.support.v4.view.ViewPager
    android:id="@+id/hsFragmentsContainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

MainViewPageAdapter。爪哇

public class MainViewViewPageAdapter extends FragmentStatePagerAdapter {
public MainViewViewPageAdapter(FragmentManager fm) {
    super(fm);
}
@Override
public int getItemPosition(@NonNull Object object) {
    return super.getItemPosition(object);
}
@Override
public Fragment getItem(int position) {
    Fragment f = null;
    switch (position) {
        case 0:
            f = new FirstFragment();
            break;
        case 1:
            f = new SecondFragment();
            break;
    }
    return f;
}
@Override
public int getCount() {
    return 2;
}}

第一个片段。爪哇

public class FirstFragment extends Fragment {
private RecyclerView pathwaysRecyclerView;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_first, container, false);
    initializeViews(view);
    initRecyclerView();
    return view;
}
private void initializeViews(View view) {
    pathwaysRecyclerView = view.findViewById(R.id.pathways_recyclerview);
}
private void initRecyclerView(){
    pathwaysRecyclerView.setLayoutManager(new GridLayoutManager(requireContext(), 2));
    PathwaysAdapter adapter = new PathwaysAdapter(new OnPathwayClickListner(),requireContext());
    pathwaysRecyclerView.setAdapter(adapter);
}

public class OnPathwayClickListner implements View.OnClickListener {
    @Override
    public void onClick(View view) {
        navigateToSecondFragment();
    }
}

private void navigateToSecondFragment(){
    Fragment fragment = new SecondFragment();
    getFragmentManager().beginTransaction().replace(R.id.fragment_pathways_view, fragment).addToBackStack(null).commit();
}}

第二个片段。爪哇

public class SecondFragment  extends Fragment {
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_second, container, false);
    return view;
}

}

PathwaysAdapter。爪哇

class PathwaysAdapter extends RecyclerView.Adapter<PathwaysAdapter.MyViewHolder>{
FirstFragment.OnPathwayClickListner onPathwayClickListner;
Context requireContext;
ArrayList<String> list;
public PathwaysAdapter(FirstFragment.OnPathwayClickListner onPathwayClickListner, Context requireContext) {
    this.onPathwayClickListner=onPathwayClickListner;
    this.requireContext=requireContext;
    list=new ArrayList<>();
    for (int i=1;i<=20;i++){
        list.add("Pathway "+i);
    }
}
@NonNull
@Override
public PathwaysAdapter.MyViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row, viewGroup, false);
    return new PathwaysAdapter.MyViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull PathwaysAdapter.MyViewHolder myViewHolder, int i) {
    myViewHolder.textview.setText(list.get(i));
}

@Override
public int getItemCount() {
    return list.size();
}

class MyViewHolder extends RecyclerView.ViewHolder {
     RelativeLayout layout;
     TextView textview;
     public MyViewHolder(@NonNull View itemView) {
        super(itemView);
        textview = itemView.findViewById(R.id.textview);
        layout = itemView.findViewById(R.id.layout);
        layout.setOnClickListener(onPathwayClickListner);
    }}}

划船。xml

<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardBackgroundColor="#FF9800"
card_view:cardCornerRadius="5dp"
card_view:cardElevation="5dp"
card_view:cardUseCompatPadding="true">
<RelativeLayout
    android:id="@+id/layout"
    android:layout_width="match_parent"
    android:layout_height="100dp">
    <TextView
        android:id="@+id/textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:textColor="#ffffff" />

</RelativeLayout>