范例HelloListView

Android docs中的范例，简单翻译整理如下。
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1、创建新项目，名称HelloListView；

2、在res/layout/目录下新建list_item.xml，内容如下：

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="10dp"
    android:textSize="16sp" >
</TextView>

3、打开HelloListView.java，修改类的继承为ListActivity：

public class HelloListView extends ListActivity {

4、修改HelloListView.java，在最前面增加变量定义：

  static final String[] COUNTRIES = new String[] {
    "Afghanistan", "Albania", "Algeria", "American Samoa", "Andorra",
    "Angola", "Anguilla", "Antarctica", "Antigua and Barbuda", "Argentina",
    "Armenia", "Aruba", "Australia", "Austria", "Azerbaijan",
    "Bahrain", "Bangladesh", "Barbados", "Belarus", "Belgium",
    "Belize", "Benin", "Bermuda", "Bhutan", "Bolivia",
    "Bosnia and Herzegovina", "Botswana", "Bouvet Island", "Brazil", "British Indian Ocean Territory",
    "British Virgin Islands", "Brunei", "Bulgaria", "Burkina Faso", "Burundi",
    "Cote d'Ivoire", "Cambodia", "Cameroon", "Canada", "Cape Verde",
    "Cayman Islands", "Central African Republic", "Chad", "Chile", "China",
    "Christmas Island", "Cocos (Keeling) Islands", "Colombia", "Comoros", "Congo",
    "Cook Islands", "Costa Rica", "Croatia", "Cuba", "Cyprus", "Czech Republic",
    "Democratic Republic of the Congo", "Denmark", "Djibouti", "Dominica", "Dominican Republic",
    "East Timor", "Ecuador", "Egypt", "El Salvador", "Equatorial Guinea", "Eritrea",
    "Estonia", "Ethiopia", "Faeroe Islands", "Falkland Islands", "Fiji", "Finland",
    "Former Yugoslav Republic of Macedonia", "France", "French Guiana", "French Polynesia",
    "French Southern Territories", "Gabon", "Georgia", "Germany", "Ghana", "Gibraltar",
    "Greece", "Greenland", "Grenada", "Guadeloupe", "Guam", "Guatemala", "Guinea", "Guinea-Bissau",
    "Guyana", "Haiti", "Heard Island and McDonald Islands", "Honduras", "Hong Kong", "Hungary",
    "Iceland", "India", "Indonesia", "Iran", "Iraq", "Ireland", "Israel", "Italy", "Jamaica",
    "Japan", "Jordan", "Kazakhstan", "Kenya", "Kiribati", "Kuwait", "Kyrgyzstan", "Laos",
    "Latvia", "Lebanon", "Lesotho", "Liberia", "Libya", "Liechtenstein", "Lithuania", "Luxembourg",
    "Macau", "Madagascar", "Malawi", "Malaysia", "Maldives", "Mali", "Malta", "Marshall Islands",
    "Martinique", "Mauritania", "Mauritius", "Mayotte", "Mexico", "Micronesia", "Moldova",
    "Monaco", "Mongolia", "Montserrat", "Morocco", "Mozambique", "Myanmar", "Namibia",
    "Nauru", "Nepal", "Netherlands", "Netherlands Antilles", "New Caledonia", "New Zealand",
    "Nicaragua", "Niger", "Nigeria", "Niue", "Norfolk Island", "North Korea", "Northern Marianas",
    "Norway", "Oman", "Pakistan", "Palau", "Panama", "Papua New Guinea", "Paraguay", "Peru",
    "Philippines", "Pitcairn Islands", "Poland", "Portugal", "Puerto Rico", "Qatar",
    "Reunion", "Romania", "Russia", "Rwanda", "Sqo Tome and Principe", "Saint Helena",
    "Saint Kitts and Nevis", "Saint Lucia", "Saint Pierre and Miquelon",
    "Saint Vincent and the Grenadines", "Samoa", "San Marino", "Saudi Arabia", "Senegal",
    "Seychelles", "Sierra Leone", "Singapore", "Slovakia", "Slovenia", "Solomon Islands",
    "Somalia", "South Africa", "South Georgia and the South Sandwich Islands", "South Korea",
    "Spain", "Sri Lanka", "Sudan", "Suriname", "Svalbard and Jan Mayen", "Swaziland", "Sweden",
    "Switzerland", "Syria", "Taiwan", "Tajikistan", "Tanzania", "Thailand", "The Bahamas",
    "The Gambia", "Togo", "Tokelau", "Tonga", "Trinidad and Tobago", "Tunisia", "Turkey",
    "Turkmenistan", "Turks and Caicos Islands", "Tuvalu", "Virgin Islands", "Uganda",
    "Ukraine", "United Arab Emirates", "United Kingdom",
    "United States", "United States Minor Outlying Islands", "Uruguay", "Uzbekistan",
    "Vanuatu", "Vatican City", "Venezuela", "Vietnam", "Wallis and Futuna", "Western Sahara",
    "Yemen", "Yugoslavia", "Zambia", "Zimbabwe"
  };

5、修改HelloListView.java的onCreate方法，内容如下：

public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, COUNTRIES));

  ListView lv = getListView();
  lv.setTextFilterEnabled(true);
  lv.setOnItemClickListener(new OnItemClickListener() {
    public void onItemClick(AdapterView<?> parent, View view,
        int position, long id) {
      // When clicked, show a toast with the TextView text
      Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
          Toast.LENGTH_SHORT).show();
    }
  });
}

6、运行项目，即可看到运行效果，如下图所示：





另，列表显示的内容也可通过XML配置的方式：
（1）修改res/values/strings.xml文件，修改后内容如下：

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, HelloListView!</string>
    <string name="app_name">HelloListView</string>
    <string-array name="countries_array">
        //……（略）
        <item>Bahrain</item>
        <item>Bangladesh</item>
        <item>Barbados</item>
        <item>Belarus</item>
        <item>Belgium</item>
        <item>Belize</item>
        <item>Benin</item>
        //……（略）
    </string-array>
</resources>

（2）修改HelloListView.java的onCreate方法，内容如下：

// 原来代码
// setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, COUNTRIES));
// 修改后的代码
String[] countries = getResources().getStringArray(R.array.countries_array);
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, countries));