Question

我是android开发的新手，所以我的动态列表有问题。

我有一个习惯类和HabitMemoryDao类，我想在主类中创建一个ListView 与习惯。有人可以写下Listview将展示所有习惯的主要课程。感谢

public class Habit {

    private String name;
    private Date startDate;
    private int duration;
    private int frequencyInWeek; // from 1 to 7
    private String awardText;


    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Date getStartDate() {
        return startDate;
    }

    public void setStartDate(Date startDate) {
        this.startDate = startDate;
    }

    public int getDuration() {
        return duration;
    }

    public void setDuration(int duration) {
        this.duration = duration;
    }

    public int getFrequencyInWeek() {
        return frequencyInWeek;
    }

    public void setFrequencyInWeek(int frequency) {
        this.frequencyInWeek = frequency;
    }

    public String getAward() {
        return awardText;
    }

    public void setAward(String award) {
        this.awardText = award;
    }
}

public class HabitMemoryDao {

    private List<Habit> habitList = new LinkedList<Habit>();

    public HabitMemoryDao() {
        Habit habit1 = new Habit();
        habit1.setName("Running");
        habit1.setDuration(30);
        habit1.setFrequencyInWeek(2);
        habit1.setStartDate(new Date());
        habitList.add(habit1);

        Habit habit2 = new Habit();
        habit2.setName("Swimming");
        habit2.setDuration(15);
        habit2.setFrequencyInWeek(7);
        habit2.setStartDate(new Date());
        habitList.add(habit2);
    }


    public List<Habit> getHabitList() {
        return habitList;
    }

Answer 1

您需要了解ListView和Adapters如何相互协作：

因此有两种方法可以启动：您可以使用ArrayAdapter，它使用Habit类的toString（）方法在ListView中显示习惯列表，或者使用更强大的类BaseAdapter。我建议你学习BaseAdapter的工作原理，因为Array adapter是BaseAdapter的子类。 Simple tutorial for BaseAdapters

顺便说一下：要求那些给你写一些具体代码的人并不是一个好主意。欢迎您提出有关具体问题的问题，人们会回答您（大多数情况下都会使用代码段）。

Answer 2

首先在toString()类

中添加Habit方法

    public class Habit{
    ...

    public String toString()
    {
      return getName()+" "+getStartDate()+" "+getDuration()+" "+getFrequencyInWeek()+" "+getAward();
    }
    ...
}

然后在你的MainActivity中查看这个基本的ListView教程，你就会明白这一点。 http://www.vogella.com/articles/AndroidListView/

Answer 3

最好的方法是创建自己的ArrayAdapter。示例实现：

public class HabitAdapter extends ArrayAdapter<Habit> {

private ArrayList<Habit> items;
Activity activity;

static class ViewHolder {
    public TextView nameTv;
    public TextView startDateTv;
    public TextView awardTextTv;

}

public HabitAdapter(Activity activity, int textViewResourceId,
        ArrayList<Habit> items) {
    super(activity, textViewResourceId, items);
    this.items = items;
    this.activity = activity;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View rowView = convertView;
    if (rowView == null) {
        LayoutInflater inflater = (LayoutInflater) activity
                .getLayoutInflater();
        rowView = inflater.inflate(R.layout.row_layout_for_one_habit, null);
        ViewHolder viewHolder = new ViewHolder();
        viewHolder.nameTv = (TextView) rowView.findViewById(R.id.nameTv);
        viewHolder.startDateTv = (TextView) rowView
                .findViewById(R.id.startDateTv);
        viewHolder.awardTextTv = (TextView) rowView
                .findViewById(R.id.awardTextTv);
        rowView.setTag(viewHolder);
    }

    ViewHolder holder = (ViewHolder) rowView.getTag();

    Habit habit = items.get(position);

    holder.nameTv.setText(habit.getName());
    holder.startDateTv.setText(habit.getStartDate());
    holder.awardTextTv.setText(habit.getAwardText());

    return rowView;
}

}

您需要为ListView的一行创建布局。根据我的实现，你应该有3个TextViews（nameTv，startDateTv，awardTextTv）。

然后在你的活动中：

ListView myList = (ListView) findViewById(R.id.myList);
HabitAdapter ha = new HabitAdapter(this, R.layout.row_layout_for_one_habit, HabitMemoryDao.getHabitList());
myList.setAdapter(ha);

ListView基于自己的类

3 个答案: