同样的代码，listview出现在activity中，但是listview没有出现在fragment中

Question

tried to solve a similar question to mine, but I failed.

1. ListView can appear in Activity but can't appear in Fragment

2. ListView on Fragment does not appear

在activity中运行的代码不在fragment中运行。我试图通过参考stackoverflow中的文章来解决它，但是失败了请教我方法。到底是什么问题？

片段

public class Fragment_Result extends Fragment {

    EditText et_search;
    ListView lv_search;

    public Fragment_Result() {

    }

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

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        final ArrayAdapter<String> adapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1);

        lv_search = (ListView) view.findViewById(R.id.lv_search);
        lv_search.setAdapter(adapter);

        adapter.add("Adam Smith");
        adapter.add("Bryan Adams");
        adapter.add("Chris Martin");
        adapter.add("Daniel Craig");
        adapter.add("Eric Clapton");
        adapter.add("Frank Sinatra");

        et_search = (EditText) view.findViewById(R.id.et_search);
        et_search.addTextChangedListener(new TextWatcher() {

            @Override
            public void afterTextChanged(Editable edit) {
                String filterText = edit.toString();
                if (filterText.length() > 0) {
                    lv_search.setFilterText(filterText);
                } else {
                    lv_search.clearTextFilter();
                }
                ((ArrayAdapter) lv_search.getAdapter()).getFilter().filter(filterText);
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

        });
    }
}

fragment.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:layout_marginTop="60dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="23sp"
        android:layout_marginLeft="25dp"
        android:layout_marginRight="8dp"
        android:id="@+id/tv_search"
        android:text="search : " />

    <EditText
        android:layout_marginTop="60dp"
        android:layout_marginRight="25dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/tv_search"
        android:id="@+id/et_search"/>

    <ListView
        android:layout_marginTop="60dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/et_search"
        android:textFilterEnabled="true"
        android:id="@+id/lv_search"/>

</RelativeLayout>

在活动和分片中使用的代码只有一部分不同。

活动列表视图：ArrayAdapter 适配器 = new ArrayAdapter(this, android.R.layout.simple_list_item_1);

片段列表视图：最终的 ArrayAdapter 适配器 = new ArrayAdapter(getActivity(), android.R.layout.simple_list_item_1);

Answer 1

在设置适配器之前添加项目。你可以试试这个吗？

   ArrayAdapter<String> adapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1);

    adapter.add("Adam Smith");
    adapter.add("Bryan Adams");
    adapter.add("Chris Martin");
    adapter.add("Daniel Craig");
    adapter.add("Eric Clapton");
    adapter.add("Frank Sinatra");

    lv_search = (ListView) view.findViewById(R.id.lv_search);
    lv_search.setAdapter(adapter);