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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