问题：

ListView数据在滚动时被清除[重复]

经嘉

2023-03-14

我正在开发一个应用程序，它显示带有复选框的listView。当我滚动列表查看复选框的值被清除时。

下面是我的代码

适配器类别:

public class Conference_listViewAdapter extends BaseAdapter {
    Activity context;
    LayoutInflater inflater;
    public static List<Model> data = null;
    ArrayList<String> id_list = new ArrayList<String>();
    ViewHolder holder;
    int pos;

    public Conference_listViewAdapter(Activity context,List<Model> list, ArrayList<String> id_list) {
        data = list;
        this.id_list = id_list;     
        this.context = context;
    }


    @Override
    public int getCount() {
        return data.size();
    }


    @Override
    public Object getItem(int position) {
        return data.get(position).getName();
    }

    @Override
    public long getItemId(int position) {
        return Long.valueOf(id_list.get(position));
    }

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

        View view = null;

        if (convertView == null) {
            LayoutInflater inflator = context.getLayoutInflater();
            view = inflator.inflate(R.layout.people_list_item1, null);
            holder = new ViewHolder();
            holder.title = (TextView) view.findViewById(R.id.tv_name);
            holder.image = (ImageView) view.findViewById(R.id.avtaar);
            holder.favorite = (CheckBox) view.findViewById(R.id.fav);
            holder.favorite.setTag(position);
            view.setTag(holder);

            holder.favorite.setTag(data.get(position));
        } else {
            view = convertView;
            ((ViewHolder) view.getTag()).favorite.setTag(data.get(position));
        }


        holder.favorite.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {                    
                Model element = (Model) holder.favorite.getTag();
                element.setSelected(buttonView.isChecked());     
                //notifyDataSetChanged();
            }
        });


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

        holder.favorite.setChecked(data.get(position).isSelected());
        holder.title.setText(data.get(position).getName());



        try {
            holder.image.setImageBitmap(openPhoto(Long.valueOf(id_list.get(position))));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return view;
    }

    class ViewHolder {
        TextView title;
        TextView model;
        ImageView image;
        CheckBox favorite;
    }


}

数据模型类

public class Model {

    private String name;
    private boolean selected;

    public Model(String name) {
        this.name = name;
        selected = false;
    }

    public String getName() {
        return name;
    }

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

    public boolean isSelected() {
        return selected;
    }

    public void setSelected(boolean selected) {
        this.selected = selected;
    }

}

不知道我哪里做错了。

共有3个答案

丁立果

2023-03-14

在类似的情况下，例如带有复选框，单选按钮，计数框等的列表视图，我使用如下方式1）保留一个大小类似于listview（行数）的数组列表2）此数组/数组列表将在适配器类的构造函数中初始化，所有位置为零3）在声明复选框并将其标记设置为位置后在getView（）中声明复选框并将其标签设置为位置

public class Conference_listViewAdapter extends BaseAdapter {
    Activity context;
    LayoutInflater inflater;
    public static List<Model> data = null;
    ArrayList<String> id_list = new ArrayList<String>();
     ArrayList<String> myarray=new java.util.ArrayList<String>();   
    ViewHolder holder;
    int pos;


    public Conference_listViewAdapter(Activity context,List<Model> list, ArrayList<String> id_list) {
        data = list;
        this.id_list = id_list;
        this.context = context;
for(int i=0;i<id_list.size();i++)
myarray.add("0");
    }


    @Override
    public int getCount() {
        return data.size();
    }


    @Override
    public Object getItem(int position) {
        return position;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

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

        View view = null;

        if (convertView == null) {
            LayoutInflater inflator = context.getLayoutInflater();
            view = inflator.inflate(R.layout.people_list_item1, null);
            holder = new ViewHolder();
            holder.title = (TextView) view.findViewById(R.id.tv_name);
            holder.image = (ImageView) view.findViewById(R.id.avtaar);
            holder.favorite = (CheckBox) view.findViewById(R.id.fav);
            holder.favorite.setTag(position);
            view.setTag(holder);

if(myarray.get(Integer.parseInt(holder.favorite.getTag().toString()).equalsIgnoreCase("1")
//make your checkbox checked
else
//keep checkbox unchecked
            holder.favorite.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {                    
   if(  isChecked)                   myarray.set(Integer.parseInt(holder.favorite.getTag().toString()),"1");    

else
myarray.set(Integer.parseInt(holder.favorite.getTag().toString()),"0"); 

notifydatasetchanged();
            });

            holder.favorite.setTag(data.get(position));
        } else {
            view = convertView;
            ((ViewHolder) view.getTag()).favorite.setTag(data.get(position));
        }


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

        holder.favorite.setChecked(data.get(position).isSelected());
        holder.title.setText(data.get(position).getName());



        try {
            holder.image.setImageBitmap(openPhoto(Long.valueOf(id_list.get(position))));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return view;
    }

    class ViewHolder {
        TextView title;
        TextView model;
        ImageView image;
        CheckBox favorite;
        Boolean selected;
    }   

}

总是这保存我的问题与列表视图滚动...

司空凌

2023-03-14

改变这个...

  @Override
public Object getItem(int position) {
    return position;
}

到..

  @Override
public Object getItem(int position) {
    return data.get(position);
}

更新：

试试这个。。

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

    View view = null;

    if (convertView == null) {
        LayoutInflater inflator = context.getLayoutInflater();
        view = inflator.inflate(R.layout.people_list_item1, null);
        holder = new ViewHolder();
        holder.title = (TextView) view.findViewById(R.id.tv_name);
        holder.image = (ImageView) view.findViewById(R.id.avtaar);
        holder.favorite = (CheckBox) view.findViewById(R.id.fav);
        holder.favorite.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {                    
               //do what you want..   
            }
        });

        view.setTag(holder);
    } else {
       holder = (ViewHolder) view.getTag();
    }

    holder.favorite.setChecked(data.get(position).isSelected());
    holder.title.setText(data.get(position).getName());



    try {
        holder.image.setImageBitmap(openPhoto(Long.valueOf(id_list.get(position))));
    } catch (Exception e) {
        e.printStackTrace();
    }

    return view;
}

支铭晨

2023-03-14

您必须保存视图持有人的状态。然后在convertView==null时设置标记，并将其置于或条件下。

检查我做的方式:

public class Conference_listViewAdapter extends ArrayAdapter<Model> {
    Activity context;
    LayoutInflater inflater;
    public static List<Model> data = null;
    ArrayList<String> id_list = new ArrayList<String>();

    int pos;


    public Conference_listViewAdapter(Activity context, List<Model> list, ArrayList<String> id_list) {
        super(context, R.layout.people_list_item1, list);
        this.context = context;
        this.data = list;
        this.id_list = id_list; 
    }



    public View getView(final int position, View convertView, ViewGroup parent) {
        View view = null;       
        if (convertView == null) {
            LayoutInflater inflator = context.getLayoutInflater();
            view = inflator.inflate(R.layout.people_list_item1, null);
            final ViewHolder holder = new ViewHolder();
            holder.title = (TextView) view.findViewById(R.id.tv_name);
            holder.image = (ImageView) view.findViewById(R.id.avtaar);
            holder.favorite = (CheckBox) view.findViewById(R.id.fav);

            view.setTag(holder);

            holder.favorite.setTag(data.get(position));

            holder.favorite.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {                    
                    Model element = (Model) holder.favorite.getTag();
                    element.setSelected(buttonView.isChecked());     
                }
            });


        } else {
            view = convertView;
            ((ViewHolder) view.getTag()).favorite.setTag(data.get(position));
        }





        ViewHolder holder = (ViewHolder) view.getTag();     
        holder.favorite.setChecked(data.get(position).isSelected());
        holder.title.setText(data.get(position).getName());

        try {
            holder.image.setImageBitmap(openPhoto(Long.valueOf(id_list.get(position))));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return view;
    }




    static class ViewHolder {
        protected TextView title;
        protected CheckBox favorite;
        ImageView image;
    }

类似资料：

数据清除时重置活动

我目前正在开发一个应用程序，但其中有一个错误。每当用户安装应用或清除数据时，应用都应重置。但相反，应用会为用户填充标准数据，而不是显示用户可以自己输入的开始屏幕。我的问题主要是关于方法。我想输入：不幸的是，我无法让它工作。有人能指出手头的问题吗？
滚动listview时切换按钮重置

我有一个代码，向用户显示一个项目列表。列表项旁边有一个切换按钮。因此，当用户打开toggle时，就会触发警报。现在的问题是，当我设置列表中第一项的切换按钮时，当我滚动到列表视图的底部并再次回到第一项时，它消失和/或重置。我完全不明白为什么要把它设置为保持选中状态。在这个论坛里请求某人帮助我。我的类CSVAdapter。我附在这里。
清除临时数据

Deprecated since version 0.52. When you delete objects (and buckets/containers), the Gateway marks the data for removal, but it is still available to users until it is purged. Since data still resides
log4j2：滚动文件未压缩，活动文件未被清除

我们最近已经将log4j2-beta9迁移到log4j2-2.0版本。我们正面临滚动文件的问题。第一个问题：滚动文件没有压缩，只保留了. log文件。第二个问题：活动文件没有被清除。日志不断被添加到同一个文件中，从而增加了文件大小。请找到我的log4j2。xml:
JavaFX 组合框项目在选择时被清除 [重复]

我有一个奇怪的问题。我在JavaFX中使用了一个ComboBox，其中每一项都是一个HBox，是一个图像和一个标签的组合。是字符串的数组列表。只是一个
如何清除滚动发光？

问题内容：默认情况下，扑增加一个发光效果到手机上我想完全删除此效果或在一个特定的滚动条上删除此效果。我知道我可以在弹跳/钳位之间进行更改。但这实际上并不能消除发光效果。我能做什么？问题答案：光晕效果来自GlowingOverscrollIndicator 通过添加ScrollBehavior 要消除这种影响，您需要指定一个custom ScrollBehavior。为此，只需将应用程序

ListView数据在滚动时被清除[重复]

共有3个答案

相关问答

相关文章

相关阅读

相关工具

相关文档