Listview 单选

落日映苍穹つ 2022-09-20 09:30 117阅读 0赞

本Demo通过两种途径实现了Listview的单选效果(自定义adapter)

1.点击Listview的item实现单选效果,就是点击item实现单选

2.点击item上的单选框实现单选效果,就是点击单选框时，实现单选效果

3.点击Listview的item实现单选效果(改进版)

先上效果图：

![SouthEast][]![Center][]![Center 1][]![SouthEast 1][]

项目的主目录是![SouthEast 2][]

具体实现如下：

主要有四个类：

MainActivity，也就是首页，主要是按钮以及文字。比较简单。

SecondActivity，是点击Listview的item实现单选效果,就是点击item实现单选 ，代码如下：

public class SecondActivity extends Activity \{ private int cur\_pos = -1;// 当前显示的一行,默认为0项选中 private List<HashMap<string object="">> list;// 数据 private ListView listview; @Override protected void onCreate(Bundle savedInstanceState) \{ super.onCreate(savedInstanceState); setContentView(R.layout.main);// 加载布局 listview = (ListView) findViewById(R.id.listview1);//绑定ID list = new ArrayList<HashMap<string object="">>();// 初始化list setData();// 加载数据 final MyAdapter adapter = new MyAdapter(this); listview.setAdapter(adapter);// 设置适配器 listview.setChoiceMode(ListView.CHOICE\_MODE\_SINGLE);// 一定要设置这个属性，否则ListView不会刷新 listview.setOnItemClickListener(new OnItemClickListener() \{ @Override public void onItemClick(AdapterView<?> arg0, View arg1, int position, long id) \{ cur\_pos = position;// 更新当前行 \} \}); \} // 填充数据 private void setData() \{ HashMap<string object=""> hashMap; for (int i = 0; i < 20; i++) \{ hashMap = new HashMap<string object="">(); hashMap.put("name", "" + i); hashMap.put("age", " " + i); hashMap.put("image", R.drawable.ic\_launcher); list.add(hashMap); \} \} // 自定义Adapter private class MyAdapter extends BaseAdapter \{ private LayoutInflater inflater; public MyAdapter(Context context) \{ inflater = (LayoutInflater) context .getSystemService(Context.LAYOUT\_INFLATER\_SERVICE); \} @Override public int getCount() \{ return list.size(); \} @Override public Object getItem(int position) \{ return list.get(position); \} @Override public long getItemId(int position) \{ return position; \} @Override public View getView(int position, View convertView, ViewGroup parent) \{ convertView = inflater.inflate(R.layout.list\_child, null, false); HashMap<string object=""> hashMap = new HashMap<string object="">(); hashMap = list.get(position);// 获取点中的数据 ViewHold viewHold = new ViewHold(); viewHold.img1 = (ImageView) convertView .findViewById(R.id.list\_child\_im1); viewHold.img2 = (ImageView) convertView .findViewById(R.id.list\_child\_im2); viewHold.tv1 = (TextView) convertView .findViewById(R.id.list\_child\_tv1); viewHold.tv2 = (TextView) convertView .findViewById(R.id.list\_child\_tv2); viewHold.tv1.setText("姓名: jack" + hashMap.get("name").toString()); viewHold.tv2.setText("年龄: " + hashMap.get("age").toString()); viewHold.img1 .setBackgroundResource((Integer) (hashMap.get("image"))); if (position == cur\_pos) \{// 如果当前的行就是ListView中选中的一行，就更改显示样式 viewHold.img2 .setBackgroundResource(R.drawable.list\_child\_sel\_chech); \} return convertView; \} class ViewHold \{ private ImageView img1; private ImageView img2; private TextView tv1; private TextView tv2; \} \} \} ThirdActivity，点击item上的单选框实现单选效果,就是点击单选框时，实现单选效果，主要代码如下： public class ThirdActivity extends Activity \{ private List<HashMap<string object="">> list; private ListView listview; private ImageView\[\] btnArr;// 数组 @Override protected void onCreate(Bundle savedInstanceState) \{ super.onCreate(savedInstanceState); setContentView(R.layout.main);// 加载布局 listview = (ListView) findViewById(R.id.listview1);// 绑定ID list = new ArrayList<HashMap<string object="">>();// 初始化list setData();// 加载数据 MyAdapter adapter = new MyAdapter(this); listview.setAdapter(adapter);// 设置适配器 \} // 填充数据 private void setData() \{ HashMap<string object=""> hashMap; for (int i = 0; i < 20; i++) \{ hashMap = new HashMap<string object="">(); hashMap.put("name", "" + i); hashMap.put("age", " " + i); hashMap.put("image", R.drawable.ic\_launcher); list.add(hashMap); \} \} // 自定义Adapter private class MyAdapter extends BaseAdapter \{ private LayoutInflater inflater; private Context myContent = null; public MyAdapter(Context context) \{ inflater = (LayoutInflater) context .getSystemService(Context.LAYOUT\_INFLATER\_SERVICE); this.myContent = context; setData(); \} // 初始化数组 private void setData() \{ btnArr = new ImageView\[list.size()\]; for (int i = 0; i < list.size(); i++) \{ btnArr\[i\] = new ImageView(myContent); btnArr\[i\].setTag(i); \} \} @Override public int getCount() \{ return list.size(); \} @Override public Object getItem(int position) \{ return list.get(position); \} @Override public long getItemId(int position) \{ return position; \} @Override public View getView(int position, View convertView, ViewGroup parent) \{ convertView = inflater.inflate(R.layout.list\_child, null, false); HashMap<string object=""> hashMap = new HashMap<string object="">(); hashMap = list.get(position); ViewHold viewHold = new ViewHold(); viewHold.img1 = (ImageView) convertView .findViewById(R.id.list\_child\_im1); viewHold.img2 = (ImageView) convertView .findViewById(R.id.list\_child\_im2); viewHold.tv1 = (TextView) convertView .findViewById(R.id.list\_child\_tv1); viewHold.tv2 = (TextView) convertView .findViewById(R.id.list\_child\_tv2); viewHold.tv1.setText("姓名: jack" + hashMap.get("name").toString()); viewHold.tv2.setText("年龄: " + hashMap.get("age").toString()); viewHold.img1 .setBackgroundResource((Integer) (hashMap.get("image"))); btnArr\[position\] = viewHold.img2; btnArr\[position\].setTag(position); convertView.setTag(viewHold); // 填设置监听器 viewHold.img2.setOnClickListener(new OnClickListener() \{ @Override public void onClick(View v) \{ // TODO Auto-generated method stub for (int i = 0; i < list.size(); i++) \{ if (v.getTag().equals(i)) \{ // 按下时改变背景 btnArr\[i\] .setBackgroundResource(R.drawable.list\_child\_sel\_chech); \} else \{ btnArr\[i\] .setBackgroundResource(R.drawable.list\_child\_sel\_nocheck); \} \} \} \}); return convertView; \} class ViewHold \{ private ImageView img1; private ImageView img2; private TextView tv1; private TextView tv2; \} \} \}

以上就是具体实现Listview的单选效果，Demo里面用到的布局、图片资源都放在下载里面去了，用到的朋友欢迎下载！有什么问题请留言！

PS 经过测试,发现点击item实现单选效果在4.0上失效,于是经过改进,

FourthActivity，点击Listview的item实现单选效果(改进版)，主要代码如下：  public class FourthActivity extends Activity \{ private List<HashMap<string object="">> list; private ListView listview; MyAdapter adapter; @Override protected void onCreate(Bundle savedInstanceState) \{ super.onCreate(savedInstanceState); setContentView(R.layout.main); listview = (ListView) findViewById(R.id.listview1); list = new ArrayList<HashMap<string object="">>(); setData(); adapter = new MyAdapter(this); listview.setAdapter(adapter); listview.setOnItemClickListener(new OnItemClickListener() \{ @Override public void onItemClick(AdapterView<?> arg0, View view, int position, long id) \{ for (int i = 0; i < list.size(); i++) \{ if (position == i) \{ if (adapter.isSelected.get(position)) \{ adapter.isSelected.put(position, false); // 同时修改map的值保存状态 \} else \{ adapter.isSelected.put(position, true); // 同时修改map的值保存状态 \} \} else \{ adapter.isSelected.put(i, false); // 同时修改map的值保存状态 \} \} adapter.notifyDataSetChanged(); \} \}); \} // 设置数据 private void setData() \{ HashMap<string object=""> hashMap; for (int i = 0; i < 20; i++) \{ hashMap = new HashMap<string object="">(); hashMap.put("name", "" + i); hashMap.put("age", " " + i); hashMap.put("image", R.drawable.ic\_launcher); list.add(hashMap); \} \} private class MyAdapter extends BaseAdapter \{ private LayoutInflater inflater; public HashMap<integer boolean=""> isSelected; public MyAdapter(Context context) \{ inflater = (LayoutInflater) context .getSystemService(Context.LAYOUT\_INFLATER\_SERVICE); init(); \} // 初始化 设置所有checkbox都为未选择 public void init() \{ isSelected = new HashMap<integer boolean="">(); for (int i = 0; i < list.size(); i++) \{ isSelected.put(i, false); \} \} @Override public int getCount() \{ return list.size(); \} @Override public Object getItem(int position) \{ return list.get(position); \} @Override public long getItemId(int position) \{ return position; \} @SuppressWarnings("unused") @Override public View getView(int position, View convertView, ViewGroup parent) \{ ViewHolder viewHold = null; if (viewHold == null) \{ viewHold = new ViewHolder(); if (convertView == null) \{ convertView = inflater.inflate(R.layout.list\_child1, null, false); \} viewHold.img1 = (ImageView) convertView .findViewById(R.id.list\_child1\_im1); viewHold.cb = (CheckBox) convertView .findViewById(R.id.list\_child1\_check2); viewHold.tv1 = (TextView) convertView .findViewById(R.id.list\_child1\_tv1); viewHold.tv2 = (TextView) convertView .findViewById(R.id.list\_child1\_tv2); \} else \{ viewHold = (ViewHolder) convertView.getTag(); \} HashMap<string object=""> hashMap = new HashMap<string object="">(); hashMap = list.get(position); viewHold.tv1.setText("姓名: jack" + hashMap.get("name").toString()); viewHold.tv2.setText("年龄: " + hashMap.get("age").toString()); viewHold.img1 .setBackgroundResource((Integer) (hashMap.get("image"))); viewHold.cb.setChecked(isSelected.get(position)); return convertView; \} class ViewHolder \{ private ImageView img1; private CheckBox cb; private TextView tv1; private TextView tv2; \} \} \}

[下载地址][Link 1]

[SouthEast]: https://img-blog.csdn.net/20140318161657593?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvenh3MTM2NTExNDg1/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast
[Center]: https://img-blog.csdn.net/20140110175841750?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvenh3MTM2NTExNDg1/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center
[Center 1]: https://img-blog.csdn.net/20140110175851828?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvenh3MTM2NTExNDg1/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center
[SouthEast 1]: /images/20220828/ae833feb0abd4854a7f35d172308ba9c.png
[SouthEast 2]: /images/20220828/e6cbc47d5de347349a817f07260052a2.png
[Link 1]: http://download.csdn.net/detail/zxw136511485/7060613