最近尝试做了个listview的多选demo，网上看其他人的例子感觉不是很难，自己动手做了下，各种细节问题，没那么简单啊。既然做了，简单写个笔记记录下。
练手demo，命名笔记乱，不要介意哦。
主界面布局activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/rootView" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="com.example.listchecked.MainActivity" > <ListView android:id="@+id/listView1" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="50dp" > </ListView> <LinearLayout android:id="@+id/button_group" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_alignLeft="@+id/listView1" android:layout_alignParentBottom="true" android:orientation="vertical" > <Button android:id="@+id/del" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="删除" /> </LinearLayout> </RelativeLayout>
列表item的布局
<?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="match_parent" android:orientation="horizontal" android:descendantFocusability="blocksDescendants" > <!--注意上面这个属性，很关键，不加会导致list无法响应OnItemClickListener中的事件--> <RelativeLayout android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1" > <CheckBox android:id="@+id/checkBox1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:clickable="false" android:focusable="false" /> <ImageView android:id="@+id/imageView1" android:layout_width="match_parent" android:layout_height="match_parent" android:scaleType="fitCenter" android:src="@drawable/ic_launcher" /> </RelativeLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/title" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Title" android:textSize="20sp" /> <TextView android:id="@+id/teacher" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Teacher" /> <TextView android:id="@+id/time" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Time" /> <TextView android:id="@+id/peopleNum" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="peopleNum" /> </LinearLayout> </LinearLayout>
这个item的布局就被在细节上坑了一次，item中添加button，checkbox,imageButton等时，会导致只响应这些控件的事件，item整体的事件就不会响应了，刚开始没有加那条属性，勾选checkbox后，点删除没有反应。这问题要发现也有点难度，之前见大神们推荐过分析布局的工具hierarchyviewer，这个工具，个人感觉和前端开发中的F12类似啊，很方便，可以看到每个布局的情况。也是好奇，点开一看，整个item的布局，从父布局，到子布局，只要checkbox可以接受click，其他全部是false，这就是问题所在了，后来百度了一下，即如上结论。
解决办法就是添加Android:descendantFocusability=”blocksDescendants” 到list的item的布局里，添加以后，发现checkbox还是可以被单独点击，不响应list的点击选中事件，很是奇怪，看其他人的例子中就没有这种现象。最后只能设置checkbox不能被点击 android:clickable=”false” 布局问题解决了，下面是java类的源码:
首先是bean类，ItemBean.java
package com.example.listchecked; public class ItemBean { private int imgRes; private String title,teacher,time; private int peopleNum,id; private boolean isChecked; private boolean isShow; public boolean isShow() { return isShow; } public void setShow(boolean isShow) { this.isShow = isShow; } public int getId() { return id; } public void setId(int id) { this.id = id; } public boolean isChecked() { return isChecked; } public void setChecked(boolean isChecked) { this.isChecked = isChecked; } public int getImgRes() { return imgRes; } public void setImgRes(int img) { this.imgRes = img; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getTeacher() { return teacher; } public void setTeacher(String teacher) { this.teacher = teacher; } public String getTime() { return time; } public void setTime(String time) { this.time = time; } public int getPeopleNum() { return peopleNum; } public void setPeopleNum(int peopleNum) { this.peopleNum = peopleNum; } }
自定义的Adapter，MyListAdapter.java
package com.example.listchecked; import java.util.List; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.CheckBox; import android.widget.CompoundButton; import android.widget.CompoundButton.OnCheckedChangeListener; import android.widget.ImageView; import android.widget.TextView; public class MyListAdapter extends BaseAdapter { private LayoutInflater inflater; private List<ItemBean> items; private ItemBean item; private OnShowItemClickListener onShowItemClickListener; public MyListAdapter(List<ItemBean> list,Context context) { items=list; inflater=LayoutInflater.from(context); } @Override public int getCount() { // TODO 自动生成的方法存根 return items.size(); } @Override public Object getItem(int position) { // TODO 自动生成的方法存根 return items.get(position); } @Override public long getItemId(int position) { // TODO 自动生成的方法存根 return items.get(position).getId(); } @Override public View getView(int position, View convertView, ViewGroup parent) { // TODO 自动生成的方法存根 ViewHolder holder;//使用ViewHolder，大神说能提升性能 if(convertView==null) { holder=new ViewHolder(); convertView=inflater.inflate(R.layout.item_view, null); holder.img=(ImageView) convertView.findViewById(R.id.imageView1); holder.cb=(CheckBox) convertView.findViewById(R.id.checkBox1); holder.title=(TextView)convertView.findViewById(R.id.title); holder.teacher=(TextView) convertView.findViewById(R.id.teacher); holder.time=(TextView) convertView.findViewById(R.id.time); holder.poeple=(TextView)convertView.findViewById(R.id.peopleNum); convertView.setTag(holder); }else { holder=(ViewHolder) convertView.getTag(); } item=items.get(position); if(item.isShow()) { holder.cb.setVisibility(View.VISIBLE); } else { holder.cb.setVisibility(View.GONE); } holder.img.setImageResource(item.getImgRes()); holder.title.setText(item.getTitle()); holder.teacher.setText("主讲："+item.getTeacher()); holder.time.setText("课时："+item.getTime()+"讲"); holder.poeple.setText("学习人数："+item.getPeopleNum()); holder.cb.setOnCheckedChangeListener(new OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if(isChecked) { item.setChecked(true); } else { item.setChecked(false); } //回调方法，讲item加入已选择的 onShowItemClickListener.onShowItemClick(item); } }); //监听后设置选择状态 holder.cb.setChecked(item.isChecked()); return convertView; } static class ViewHolder { ImageView img; CheckBox cb; TextView title,teacher,time,poeple; } public interface OnShowItemClickListener { public void onShowItemClick(ItemBean bean); } public void setOnShowItemClickListener(OnShowItemClickListener onShowItemClickListener) { this.onShowItemClickListener = onShowItemClickListener; } }
最后是MainActivity.java
package com.example.listchecked; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.Button; import android.widget.LinearLayout; import android.widget.ListView; import android.widget.RelativeLayout; import android.widget.Toast; import com.example.listchecked.MyListAdapter.OnShowItemClickListener; public class MainActivity extends Activity implements OnShowItemClickListener { private ListView listView; private List<ItemBean> dataList,selectedList; private MyListAdapter myAdapter; private RelativeLayout rootView; private LinearLayout menuView; private LinearLayout openView; private static boolean isShow; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); isShow=false; setContentView(R.layout.activity_main); Button delbtn=(Button) findViewById(R.id.del); rootView=(RelativeLayout) findViewById(R.id.rootView); menuView=(LinearLayout) findViewById(R.id.button_group); listView=(ListView) findViewById(R.id.listView1); dataList=new ArrayList<ItemBean>(); selectedList=new ArrayList<ItemBean>(); for(int i=0;i<10;i++) { ItemBean item=new ItemBean(); item.setId(i); item.setImgRes(R.drawable.ic_launcher); item.setTitle("第"+item.getId()+"个"); item.setTeacher("杨老师"); item.setTime("34"); item.setPeopleNum(i+1*100); item.setChecked(false); item.setShow(isShow); dataList.add(item); } myAdapter=new MyListAdapter(dataList, this); myAdapter.setOnShowItemClickListener(MainActivity.this); listView.setAdapter(myAdapter); delbtn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO 自动生成的方法存根 showMenu(); isShow=true; selectedList.clear(); for(ItemBean item:dataList) { item.setShow(isShow); } myAdapter.notifyDataSetChanged(); } }); listView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // TODO 自动生成的方法存根 if (isShow) { ItemBean item = dataList.get(position); boolean isChecked = item.isChecked(); if (isChecked) { item.setChecked(false); } else { item.setChecked(true); } myAdapter.notifyDataSetChanged(); Log.d("select",selectedList.size()+""); } } }); } //显示选择删除等的菜单 private void showMenu() { RelativeLayout.LayoutParams lp=new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT); lp.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM); LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE); openView=(LinearLayout) inflater.inflate(R.layout.delmenu_layout, null); rootView.removeView(menuView); rootView.addView(openView,lp); final Button sBtn=(Button) openView.findViewById(R.id.selectAll); Button dBtn=(Button) openView.findViewById(R.id.del_button); Button cBtn= (Button) openView.findViewById(R.id.cancel_button); sBtn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO 自动生成的方法存根 if ("全选".equals(sBtn.getText().toString())) { for (ItemBean bean : dataList) { if (!bean.isChecked()) { bean.setChecked(true); if (!selectedList.contains(bean)) { selectedList.add(bean); } } } myAdapter.notifyDataSetChanged(); sBtn.setText("反选"); } else if ("反选".equals(sBtn.getText().toString())) { for (ItemBean bean : dataList) { bean.setChecked(false); if (!selectedList.contains(bean)) { selectedList.remove(bean); } } myAdapter.notifyDataSetChanged(); sBtn.setText("全选"); } } }); dBtn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO 自动生成的方法存根 if (selectedList!=null && selectedList.size()>0) { dataList.removeAll(selectedList); myAdapter.notifyDataSetChanged(); selectedList.clear(); } else { Toast.makeText(MainActivity.this, "请选择条目", Toast.LENGTH_SHORT).show(); } } }); cBtn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO 自动生成的方法存根 if (isShow) { selectedList.clear(); for (ItemBean bean : dataList) { bean.setChecked(false); bean.setShow(false); } myAdapter.notifyDataSetChanged(); isShow = false; restoreView(); } } }); } @Override public void onShowItemClick(ItemBean bean) { // TODO 自动生成的方法存根 if (bean.isChecked() && !selectedList.contains(bean)) { selectedList.add(bean); } else if (!bean.isChecked() && selectedList.contains(bean)) { selectedList.remove(bean); } } private void restoreView() { rootView.addView(menuView); if(openView!=null) { rootView.removeView(openView); openView=null; } } }
最后还有那个小菜单的布局，还是放上吧
<?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="horizontal" > <Button android:id="@+id/selectAll" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:text="全选" /> <Button android:id="@+id/del_button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:text="删除" /> <Button android:id="@+id/cancel_button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:text="取消" /> </LinearLayout>
全部代码都放上了，如果不想复制粘贴，GitHub地址：https://github.com/2767321434/ListChecked
以上就是本文的全部内容，希望对大家学习Android软件编程有所帮助。