android - 一个 ListView 中的两个适配器

Question

我提前为提出一个已经存在的问题道歉，但我似乎无法让它工作(我也是 Android Studios 的新手)。

我正在创建一个家庭作业应用程序，该应用程序通过弹出窗口获取用户输入，并将用户输入存储为字符串数组，然后将其转换为适配器。然后使用适配器通过 ListView 将数组的值打印到用户的屏幕上。

我遇到的问题是我有两列:一列用于类(class)名称，一列用于类(class)作业。我能够使用一个适配器来显示类名称的所有值，但另一列保留默认提示值。我正在尝试根据每个类名称及其各自的分配相应地显示两列。

我知道我必须以某种方式将适配器合并为一个，但我不知道该怎么做(请参阅 Java for Planner)。如果有人可以帮助我，我将不胜感激。

这是屏幕的 Java

package com.example.johnta.homeworkappv2;

import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.PopupWindow;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.Arrays;

public class PlannerActivity extends ListActivity {

    public static ArrayList<String> arrayList, arrayList_assignments;

    private static ArrayAdapter<String> adapter, adapter_assignments;
    private static EditText txtInput;
    private static TextView tvMsg;
    private static PopupWindow popUpWindow;
    private static LinearLayout mainLayout;

    private String [] items = {"Physics","Humanities","Math","STEM"};
    private String [] list_of_assignments = {"Notes","Reading","Problems","Engineering"};
    private String [][] twoDimensionalItems = {{"Physics","Notes"}};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        popUpWindow = new PopupWindow(this);
        mainLayout = new LinearLayout(this);

        setContentView(R.layout.activity_planner);

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

        arrayList = new ArrayList<>(Arrays.asList(items));
        arrayList_assignments = new ArrayList<>(Arrays.asList(list_of_assignments));

        adapter = new ArrayAdapter<String>(this,R.layout.editlistitems,R.id.name_of_class,arrayList);
        adapter_assignments = new ArrayAdapter<String>(this,R.layout.editlistitems,R.id.homework_description,arrayList_assignments);

        listView.setAdapter(adapter);


        txtInput = (EditText)findViewById(R.id.name_of_class);
    }

    public void makeEditable(View v) {

    }

    public void onClickEdit (View v) {
        startActivity(new Intent(PlannerActivity.this,popup.class));

    }

    public static void addItemToArray (String itemToAdd) {
        arrayList.add(itemToAdd);
        adapter.notifyDataSetChanged();
    }

}

这是弹出窗口的 Java

package com.example.johnta.homeworkappv2;

import android.app.Activity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.View;
import android.widget.EditText;

/**
 * Created by johnta on 4/3/17.
 */

public class popup extends Activity {

    private EditText txtInput;
    private EditText input_assignment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.plannerpopup);

        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);

        int width = dm.widthPixels;
        int height = dm.heightPixels;

        getWindow().setLayout((int)(width*0.8),(int)(height*0.6));

        txtInput = (EditText)findViewById(R.id.name_of_class);
        input_assignment = (EditText)findViewById(R.id.class_assignment);
    }

    public void onClickEditList (View v) {
        String newItem = txtInput.getText().toString();
        PlannerActivity.addItemToArray(newItem);
        super.onBackPressed();
    }
}

**这是 activity_planner 的 XML **

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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="com.example.johnta.homeworkappv2.settings"
    android:background="#87ceeb">

    <RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:layout_constraintLeft_creator="1"
        tools:layout_constraintTop_creator="1">

        <ImageView
            android:id="@+id/planner_picture"
            android:layout_width="150dp"
            android:layout_height="150dp"
            android:layout_marginTop="5dp"
            android:background="@drawable/roundbutton"
            app:srcCompat="@drawable/planner10pad"
            android:layout_centerHorizontal="true"
            android:layout_marginBottom="35dp" />

        <Button
            android:id="@+id/edit_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Edit"
            tools:layout_editor_absoluteX="16dp"
            tools:layout_editor_absoluteY="130dp"
            android:layout_marginTop="154dp"
            android:layout_alignParentTop="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:onClick="onClickEdit"/>

        <Button
            android:id="@+id/copy_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Copy"
            android:layout_alignBaseline="@+id/edit_button"

            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true"
            android:layout_alignRight="@id/planner_picture"
            />

        <TextView
            android:id="@+id/textView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Planner"
            android:textColor="#000000"
            android:textSize="32sp"
            android:layout_alignTop="@+id/edit_button"
            android:gravity="center"
            android:layout_alignBottom="@+id/edit_button"
            android:layout_alignLeft="@+id/planner_picture"
            android:layout_alignStart="@+id/planner_picture"
            android:layout_alignRight="@+id/planner_picture"
            android:layout_alignEnd="@+id/planner_picture" />

        <ListView
            android:id="@android:id/list"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="#ffffff"
            android:layout_below="@+id/edit_button"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_weight="1"
            android:divider="#000000">
        </ListView>

    </RelativeLayout>

</android.support.constraint.ConstraintLayout>

**这是 Planner 中 ListView 的 XML **

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="horizontal" >

    <TextView
        android:id="@+id/name_of_class"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="24sp"
        android:paddingTop="3dp"
        android:paddingBottom="3dp"
        android:paddingLeft="5dp"
        android:paddingRight="3dp"
        android:hint="Class name"
        android:textStyle="bold"
        />

    <TextView
        android:id="@+id/homework_description"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="3dp"
        android:paddingBottom="3dp"
        android:paddingLeft="3dp"
        android:hint="Class Assignment"
        android:textSize="20sp"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:inputType="textMultiLine"
        android:layout_alignBaseline="@+id/name_of_class"
        android:layout_alignBottom="@+id/name_of_class"
        android:layout_toRightOf="@+id/name_of_class"
        android:layout_toEndOf="@+id/name_of_class" />
</RelativeLayout>

Answer 1

The issue I am having is that I have two columns: one for the class name and one for the class assignment. I am able to use one adapter to display all the values for the class names, but the other column is left with the default hint value.

不要为此存储两个数组列表。

您可以使用 Hashmap 和 SimpleAdapter 或使用 Java 的 OOP 功能为某些包含两个字符串的 Plan 类创建自定义 ArrayAdapter(注意 class 是 Java 中的保留字)。

详情https://github.com/codepath/android_guides/wiki/Using-an-ArrayAdapter-with-ListView#using-a-custom-arrayadapter

可能也值得研究 Android 数据绑定(bind)