To create a text entry widget that provides auto-complete suggestions, use the {@link android.widget.AutoCompleteTextView} widget. Suggestions are received from a collection of strings associated with the widget through an {@link android.widget.ArrayAdapter}.
In this tutorial, you will create a {@link android.widget.AutoCompleteTextView} widget that provides suggestions for a country name.
list_item.xml and save it inside the
res/layout/ folder. Edit the file to look like this:
<?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"
android:textColor="#000">
</TextView>
This file defines a simple {@link android.widget.TextView} that will be used for each item that appears in the list of suggestions.
res/layout/main.xml file and insert the following:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="5dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Country" />
<AutoCompleteTextView android:id="@+id/autocomplete_country"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"/>
</LinearLayout>
The {@link android.widget.TextView} is a label that introduces the {@link android.widget.AutoCompleteTextView} widget.
HelloAutoComplete.java and insert the following code for the {@link
android.app.Activity#onCreate(Bundle) onCreate()} method:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
AutoCompleteTextView textView = (AutoCompleteTextView) findViewById(R.id.autocomplete_country);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.list_item, COUNTRIES);
textView.setAdapter(adapter);
}
After the content view is set to the main.xml layout, the {@link
android.widget.AutoCompleteTextView} widget is captured from the layout with {@link
android.app.Activity#findViewById(int)}. A new {@link
android.widget.ArrayAdapter} is then initialized to bind the list_item.xml layout
to each list item in the COUNTRIES string array (defined in the next step).
Finally, {@link android.widget.AutoCompleteTextView#setAdapter(T) setAdapter()} is called to
associate the {@link android.widget.ArrayAdapter} with the
{@link android.widget.AutoCompleteTextView} widget so that the string array will populate
the list of suggestions.
HelloAutoComplete class, add the string array:
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"
};
This is the list of suggestions that will be provided in a drop-down list when the user types into the {@link android.widget.AutoCompleteTextView} widget.
As you type, you should see something like this:
Note that using a hard-coded string array is not a recommended design practice because your application code should focus on behavior, not content. Application content such as strings should be externalized from the code in order to make modifications to the content easier and facilitate localization of the content. The hard-coded strings are used in this tutorial only to make it simple and focus on the {@link android.widget.AutoCompleteTextView} widget. Instead, your application should declare such string arrays in an XML file. This can be done with a {@code <string-array<} resource in your project {@code res/values/strings.xml} file. For example:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="countries_array">
<item>Bahrain</item>
<item>Bangladesh</item>
<item>Barbados</item>
<item>Belarus</item>
<item>Belgium</item>
<item>Belize</item>
<item>Benin</item>
</string-array>
</resources>
To use these resource strings for the {@link android.widget.ArrayAdapter}, replace the original {@link android.widget.ArrayAdapter} constructor line with the following:
String[] countries = getResources().getStringArray(R.array.countries_array); ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.list_item, countries);