WangWY 2012-04-13
使用过ListView的开发人员都知道,ListView在一般情况下只能对每条记录设置一个监听事件。如果想在其中添加多个事件,就需要自定义Adapter。
下面介绍一下如何自定义adapter以及如何在一个Item中绑定多个事件。
这里我们需要两个XML文件、两个java类。分别是存放ListView的XML、ListViewItem的XML、Activity类和Adapter类。
首先说说两个XML文件。
main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding= "10dip" android:orientation="vertical" > <ListView android:id="@id/android:list" android:layout_width = "fill_parent" android:layout_height = "fill_parent" /> </LinearLayout>
注意:这里的ListView中id使用了android自定义的: @id/android:list
lvItem.xml
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" android:descendantFocusability="blocksDescendants" android:padding="5dip" > <ImageView android:id="@+id/ItemImage" android:layout_width="wrap_content" android:layout_height="wrap_content" android:padding="5dip" /> <ImageButton android:id="@+id/ItemCloseWin" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignBottom="@+id/ItemWinName" android:layout_alignTop="@+id/ItemWinName" android:layout_alignParentRight="true" android:background="#e0000000" android:focusable="false" android:gravity="left|center_vertical" android:src="@android:drawable/ic_menu_close_clear_cancel" /> <ImageButton android:id="@+id/ItemEmail" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignBottom="@id/ItemWinName" android:layout_alignTop="@id/ItemWinName" android:layout_toLeftOf="@id/ItemCloseWin" android:background="#e0000000" android:focusable="false" android:gravity="left|center_vertical" android:src="@android:drawable/ic_dialog_email" /> <TextView android:id="@+id/ItemWinName" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignBottom="@id/ItemImage" android:layout_alignTop="@id/ItemImage" android:layout_toLeftOf="@id/ItemEmail" android:layout_toRightOf="@id/ItemImage" android:gravity="left|center_vertical" android:text="title" android:textSize="20dip" /> </RelativeLayout>
接下来看看Activity
package cn.mutil; import java.util.ArrayList; import java.util.HashMap; import android.app.ListActivity; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; /** * ListView item 多事件Activity * @author lihua * */ public class LvWithButtonActivity extends ListActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // 关联Layout中的ListView ListView vncListView = (ListView) findViewById(android.R.id.list); // 生成动态数组,加入数据 ArrayList<HashMap<String, Object>> remoteWindowItem = new ArrayList<HashMap<String, Object>>(); for (int i = 0; i < 10; i++) { HashMap<String, Object> map = new HashMap<String, Object>(); map.put("ItemImage", R.drawable.ic_launcher); // 图像资源的ID map.put("ItemWinName", "Window ID " + i); map.put("ItemEmail", android.R.drawable.ic_dialog_email); map.put("ItemCloseWin", android.R.drawable.ic_menu_close_clear_cancel); remoteWindowItem.add(map); } // 生成适配器的Item和动态数组对应的元素 LvButtonAdapter listItemAdapter = new LvButtonAdapter(this, remoteWindowItem, // 数据源 R.layout.lvitem, // ListItem对应的XML // 动态数组与ImageItem对应的子项 new String[] { "ItemImage", "ItemWinName","ItemEmail", "ItemCloseWin" }, // ImageItem的XML文件里面的一个ImageView,两个TextView ID new int[] { R.id.ItemImage, R.id.ItemWinName, R.id.ItemEmail, R.id.ItemCloseWin }); vncListView.setAdapter(listItemAdapter); /** * 设置整个Item被点击的事件 * 该事件在其他有事件的组件未被点击时触发 */ vncListView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> adapter, View view, int position,long arg3) { TextView content = (TextView)view.findViewById(R.id.ItemWinName); Toast.makeText(LvWithButtonActivity.this, content.getText().toString() , Toast.LENGTH_SHORT).show(); } }); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { super.onListItemClick(l, v, position, id); l.getItemAtPosition(position); } }
最后一个也是最重要的一个,自定义adapter
package cn.mutil; import java.util.ArrayList; import java.util.HashMap; import java.util.Map; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageButton; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; public class LvButtonAdapter extends BaseAdapter { private class ButtonViewHolder { ImageView appIcon; TextView appName; ImageButton buttonEmail; ImageButton buttonClose; } private ArrayList<HashMap<String, Object>> mAppList;//用于存放传递过来显示于ListView中的 数据 private LayoutInflater mInflater; private Context mContext; private String[] keyString; private int[] valueViewID; private ButtonViewHolder holder; public LvButtonAdapter(Context c,//上下文 ArrayList<HashMap<String, Object>> appList,//绑定数据 int resource00000,//ListView行记录layout String[] from, int[] to) { mAppList = appList; mContext = c; mInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE); keyString = new String[from.length]; valueViewID = new int[to.length]; System.arraycopy(from, 0, keyString, 0, from.length); System.arraycopy(to, 0, valueViewID, 0, to.length); } @Override public int getCount() { return mAppList.size(); } @Override public Object getItem(int position) { return mAppList.get(position); } @Override public long getItemId(int position) { return position; } /** * 删除数据集中的值 * @param position */ public void removeItem(int position) { mAppList.remove(position); this.notifyDataSetChanged(); } /** * 改变数据集中的值 * @param position * @param map */ public void changeItem(int position,HashMap<String, Object> map){ mAppList.remove(position); mAppList.add(position, map); this.notifyDataSetChanged(); } @Override public View getView(int position, View convertView, ViewGroup parent) { if (convertView != null) { holder = (ButtonViewHolder) convertView.getTag(); } else { convertView = mInflater.inflate(R.layout.lvitem, null); holder = new ButtonViewHolder(); holder.appIcon = (ImageView) convertView .findViewById(valueViewID[0]);//可以将valueViewID[0]替换成R.id.xxx holder.appName = (TextView) convertView .findViewById(valueViewID[1]); holder.buttonEmail = (ImageButton) convertView .findViewById(valueViewID[2]); holder.buttonClose = (ImageButton) convertView .findViewById(valueViewID[3]); convertView.setTag(holder); } HashMap<String, Object> appInfo = mAppList.get(position); if (appInfo != null) { String aname = (String) appInfo.get(keyString[1]); int mid = (Integer) appInfo.get(keyString[0]); int eid = (Integer) appInfo.get(keyString[2]); int bid = (Integer) appInfo.get(keyString[3]); holder.appName.setText(aname); holder.appName.setOnClickListener(new LvButtonListener(position)); holder.appIcon.setImageDrawable(holder.appIcon.getResources().getDrawable(mid)); holder.buttonEmail.setImageDrawable(holder.buttonEmail.getResources().getDrawable(eid)); holder.buttonEmail.setOnClickListener(new LvButtonListener(position)); holder.buttonClose.setImageDrawable(holder.buttonClose.getResources().getDrawable(bid)); holder.buttonClose.setOnClickListener(new LvButtonListener(position)); } return convertView; } /** * 按钮事件监听 * @author lihua * */ private class LvButtonListener implements View.OnClickListener { private int position; LvButtonListener(int pos) { position = pos; } @Override public void onClick(View v) { int vid = v.getId(); HashMap<String, Object> curMap = (HashMap<String, Object>)getItem(position); if (vid == holder.buttonClose.getId()){ //删除一行记录 Toast.makeText(mContext,"position:"+position+",data is being Deleted", Toast.LENGTH_LONG).show(); removeItem(position); //可以在这里操作数据库或更新服务端数据 }else if(vid == holder.buttonEmail.getId()){//发送邮件 Toast.makeText(mContext, "position:"+position+",sending email to xxx!", Toast.LENGTH_SHORT).show(); //可以在这里操作数据库或更新服务端数据 }else if(vid == holder.appName.getId()){//设置名称 Toast.makeText(mContext, "position is "+position+", appName:"+curMap.get("ItemWinName").toString(), Toast.LENGTH_SHORT).show(); curMap.put("ItemWinName", System.currentTimeMillis()+""); changeItem(position,curMap); //可以在这里操作数据库或更新服务端数据 } } } }