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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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