问如何在Android Studio中为ListView (每个列表)添加复选框
EN

Stack Overflow用户

提问于 2021-03-10 12:19:42

回答 2查看 31关注 0票数 0

基本上，我正在创建一个任务/待办事项列表应用程序，但我无法弄清楚这一部分。我想在每个任务旁边添加一个复选框，并能够检查它们。

这是MainActivity.java

public class MainActivity extends AppCompatActivity {

static ArrayList<String> notes = new ArrayList<>();
static ArrayAdapter arrayAdapter;


public boolean onCreateOptionsMenu(Menu menu) {

    MenuInflater menuInflater = getMenuInflater();
    menuInflater.inflate(R.menu.main_menu, menu);

    return super.onCreateOptionsMenu(menu);
}


public boolean onOptionsItemSelected(MenuItem item) {
    super.onOptionsItemSelected(item);
    if (item.getItemId() == R.id.add_note) {
        Intent intent = new Intent(getApplicationContext(),
                note_editor.class);
        startActivity(intent);
        return true;
    }
    return false;
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    ListView listView = (ListView) findViewById(R.id.listView);

    SharedPreferences sharedPreferences =
            getApplicationContext().getSharedPreferences
                    ("com.example.assignment1", Context.MODE_PRIVATE);


    HashSet<String> set = (HashSet<String>)
            sharedPreferences.getStringSet("notes", null);

    if (set == null) {
        notes.add("Add Your Task Hereee");
    } else {
        notes = new ArrayList(set);
    }


    arrayAdapter = new ArrayAdapter
            (this, android.R.layout.simple_list_item_1, notes);

    listView.setAdapter(arrayAdapter);


    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        public void onItemClick
        (AdapterView<?> adapterView, View view, int i, long l) {

            Intent intent = new Intent(getApplicationContext(),
                    note_editor.class);
            intent.putExtra("noteId", i);
            startActivity(intent);


        }

    });

我的main.xml

<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"
    tools:context=".MainActivity">

    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_alignParentEnd="true"
        android:id="@+id/listView" />

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentEnd="true"
        android:layout_alignParentBottom="true"
        android:layout_marginEnd="32dp"
        android:layout_marginBottom="28dp"
        android:backgroundTint="#4BB3A9"
        android:src="@drawable/add_task"/>

</RelativeLayout>

我希望它看起来像这样“：I drew the checkboxes here

我还有另一个类，用于编辑任务以及启动画面，但我认为在这里没有必要这样做。任何帮助都将不胜感激！

java

android

xml

checkbox

回答 2

Stack Overflow用户

发布于 2021-03-10 13:16:42

你可以使用回收器视图代替列表视图。参考代码如下：

创建自定义适配器并将其设置为您的回收器视图，并像recyclerView.setAdapter(CustomAdapter(new ArrayList("AAAAA","BBBBB","CCCCC","DDDDD"),getContext()));一样调用它

自定义适配器

public class CustomAdapter extends ArrayAdapter<String> {

    private ArrayList<String> dataSet;

    // View lookup cache
    private static class ViewHolder {
        CheckedTextView checkedTextView;
    }

    public CustomAdapter(ArrayList<String> data, Context context) {
        super(context, R.layout.list_item, data);
        this.dataSet = data;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        // Check if an existing view is being reused, otherwise inflate the view
        ViewHolder viewHolder; // view lookup cache stored in tag

        if (convertView == null) {

            viewHolder = new ViewHolder();
            LayoutInflater inflater = LayoutInflater.from(getContext());
            convertView = inflater.inflate(R.layout.list_item, parent, false);
            viewHolder.checkedTextView = convertView.findViewById(R.id.check_box);
            viewHolder.checkedTextView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    viewHolder.checkedTextView.setChecked(!viewHolder.checkedTextView.isChecked());
                }
            });
            convertView.setTag(viewHolder);
        } else {
            viewHolder = (ViewHolder) convertView.getTag();
        }

        viewHolder.checkedTextView.setText(dataSet.get(position));

        return convertView;
    }
}

每个列表项的XML代码: list_item.xml

<CheckedTextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/check_box"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginEnd="10dp"
android:checked="false"
android:checkMark="?android:attr/listChoiceIndicatorMultiple"
android:gravity="center"
android:text="Check Me"
/>