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Android ListView--实现ListView条目中指

Android ListView--实现ListView条目中指

作者: xiesen | 来源:发表于2019-07-16 15:42 被阅读0次

1. 目的:

在ListView 的每一个item 条目中,加入一个删除按钮,当点击删除按钮的时候,删除该条目;点击删除按钮之外的条目内容时响应条目的点击事件。具体效果如下所示:


ListView指定控件的点击事件.gif

2 . 实现思路及步骤:

(1)
让当前activity实现clickListener(或者在activity中单独new 一个监听器对象)。
(2)
创建lv 适配器的时候,通过构造将监听器传递进适配器,并把该监听器设置给要点击的控件
(3)
适配器中,通过被点击控件的setTag 方法将当前条目position 传递出去
(4)
在activity中 clcikListener 的 click方法中,通过getTag获取被点击控件所在条目的位置,从而做进一步的操作

3 . 完整示例代码:

ClickTheLvItemContentActivity.java

public class ClickTheLvItemContentActivity extends AppCompatActivity implements View.OnClickListener {

    private List<String>            dataList;
    private ClickItemContentAdapter adapter;

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

        //初始化数据
        dataList = new ArrayList<>();
        for (int i = 0; i < 30; i++) {
            dataList.add("张三"+i );
        }

        //获取lv 并设置适配器
        ListView listView = (ListView) findViewById(R.id.lv_clickItemContent);
        //创建适配器,传递数据集合,以及条目中被点击控件的的点击监听
        adapter = new ClickItemContentAdapter(ClickTheLvItemContentActivity.this, dataList);
        listView.setAdapter(adapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(ClickTheLvItemContentActivity.this, position + "号位置的条目被点击", Toast.LENGTH_SHORT).show();
            }
        });
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.iv_del:   //lv条目中 iv_del
                final int position = (int) v.getTag(); //获取被点击的控件所在item 的位置,setTag 存储的object,所以此处要强转
            
                //点击删除按钮之后,给出dialog提示
                AlertDialog.Builder builder = new AlertDialog.Builder(ClickTheLvItemContentActivity.this);
                builder.setTitle( position + "号位置的删除按钮被点击,确认删除?");
                builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                    }
                });
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dataList.remove(position);
                        adapter.notifyDataSetChanged();
                    }
                });
                builder.show();
                break;
        }
    }
}

activity_click_item_content.xml(actvitiy的布局文件)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:orientation="vertical">
    <ListView
        android:id="@+id/lv_clickItemContent"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    </ListView>

</LinearLayout>

ClickItemContentAdapter.java(LV适配器 )

public class ClickItemContentAdapter extends BaseAdapter {
    private final View.OnClickListener listener;
    private final List<String>         dataList;

    public ClickItemContentAdapter(View.OnClickListener listener, List<String> dataList) {
        this.listener = listener;
        this.dataList = dataList;
    }

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

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

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_click_item_content, parent,false);
            holder.iv_del = (ImageView) convertView.findViewById(R.id.iv_del);
            holder.tv_title = (TextView) convertView.findViewById(R.id.tv_title);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        
        holder.tv_title.setText(dataList.get(position));

        //给要被点击的控件加入点击监听,具体事件在创建adapter的地方实现
        holder.iv_del.setOnClickListener(listener);
        //通过setTag 将被点击控件所在条目的位置传递出去
        holder.iv_del.setTag(position);

        return convertView;
    }

    class ViewHolder {
        TextView  tv_title;
        ImageView iv_del;
    }
}

item_click_item_content.xml(LV条目布局)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="50dp"
              android:orientation="horizontal">
    <TextView
        android:id="@+id/tv_title"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:background="#44ff0000"
        android:gravity="center"
        android:text="abc"/>

    <ImageView
        android:id="@+id/iv_del"
        android:layout_width="@dimen/dp30"
        android:layout_height="@dimen/dp30"
        android:layout_gravity="center"
        android:layout_marginLeft="@dimen/dp10"
        android:layout_marginRight="@dimen/dp10"
        android:src="@drawable/delete"/>
</LinearLayout>

4 . 总结

a、在Adapter适配器中添加点击监听属性并构造方法

private View.OnClickListener listener;

b、在Activity实现View.OnClickListener接口

c、监听条目点击时间

  
  listView.setAdapter(adapter);
  listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(ClickTheLvItemContentActivity.this, position + "号位置的条目被点击", Toast.LENGTH_SHORT).show();
            }
        });

d、条目按钮事件

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.iv_del:   //lv条目中 iv_del
                final int position = (int) v.getTag(); //获取被点击的控件所在item 的位置,setTag 存储的object,所以此处要强转
            
                //点击删除按钮之后,给出dialog提示
                AlertDialog.Builder builder = new AlertDialog.Builder(ClickTheLvItemContentActivity.this);
                builder.setTitle( position + "号位置的删除按钮被点击,确认删除?");
                builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                    }
                });
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dataList.remove(position);
                        adapter.notifyDataSetChanged();
                    }
                });
                builder.show();
                break;
        }
    }

e、通知listview中的数据更新

adapter.notifyDataSetChanged();

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