Android常见UI组件之ListView（二）——定制ListView
这一篇接上篇，展示ListView中选择多个项及实现筛选功能~
1、在位于res/values文件夹下的strings.xml文件中添加如下代码：
<?xml version="1.0" encoding="utf-8"?><resources> <string name="app_name">BasicView5</string> <string name="action_settings">Settings</string> <string name="hello_world">Hello world!</string> <string-array name="presidents_array"> <item>Dwight D. Eisenhower</item> <item>John F. Kennedy</item> <item>Lyndon B. Johnson</item> <item>Richard Nixon</item> <item>Gerald Ford</item> <item>Jimmy Carter</item> <item>Ronald Reagan</item> <item>George H.W. Bush</item> <item>Bill Clinton</item> <item>George W. Bush</item> <item>Barack Obama</item> </string-array></resources>2、修改上一篇中的BasicView5.java文件的代码，修改后的代码如下：
package com.example.basicview5;import android.os.Bundle;import android.app.Activity;import android.app.ListActivity;import android.view.Menu;import android.view.View;import android.widget.ArrayAdapter;import android.widget.ListView;import android.widget.Toast;public class MainActivity extends ListActivity { String[] presidents;//将列表信息存储在strings.xml文件中，再以编程方式读取 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // ---no need to call this---// // setContentView(R.layout.activity_main); ListView listView = getListView();// 获取ListActivity的列表视图 listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);// 可以选择多个项 listView.setTextFilterEnabled(true);//启用筛选功能，在键盘上输入，ListView自动筛选 // getResources()方法以编程方式检索与应用程序捆绑的资源 presidents = getResources().getStringArray(R.array.presidents_array); setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_checked, presidents)); } public void onListItemClick(ListView parent, View v, int position, long id) { Toast.makeText(this, "You have selected " + presidents[position], Toast.LENGTH_SHORT).show(); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; }}
3、运行程序，效果如下：
4、在activity_main.xml文件中添加代码如下：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" 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=".MainActivity" > <Button android:id="@+id/btn" android:layout_width="fill_parent" android:layout_height="wrap_content" android:onClick="onClick" android:text="Show selected items" /> <ListView android:id="@+id/android:list" android:layout_width="wrap_content" android:layout_height="wrap_content" /></LinearLayout>
5、在BasicView5.java文件中添加代码，如下：package com.example.basicview5;import android.os.Bundle;import android.app.Activity;import android.app.ListActivity;import android.view.Menu;import android.view.View;import android.widget.ArrayAdapter;import android.widget.ListView;import android.widget.Toast;public class MainActivity extends ListActivity { String[] presidents;//将列表信息存储在strings.xml文件中，再以编程方式读取 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // ---need to call this---// setContentView(R.layout.activity_main);//由于在xml文件中添加了一个ListView部分填充一个活动，所以需要加载活动内容。 ListView listView = getListView();// 获取ListActivity的列表视图 listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);// 可以选择多个项 listView.setTextFilterEnabled(true);//启用筛选功能，在键盘上输入，ListView自动筛选 // getResources()方法以编程方式检索与应用程序捆绑的资源 presidents = getResources().getStringArray(R.array.presidents_array); setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_checked, presidents)); } public void onListItemClick(ListView parent, View v, int position, long id) { Toast.makeText(this, "You have selected " + presidents[position], Toast.LENGTH_SHORT).show(); } public void onClick(View view) { ListView listView = getListView(); String itemsSelected = "Selected items: \n"; for(int i = 0; i < listView.getCount(); i++) { if(listView.isItemChecked(i)) {//找出被选中的item itemsSelected += listView.getItemAtPosition(i) + "\n";//返回指定位置的項的名称 } } Toast.makeText(this, itemsSelected, Toast.LENGTH_LONG).show(); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; }}
6、运行效果如下：
筛选并选中几个项，再按按钮显示选择了那些项：
