07.3. Android Alert message, List, Dropdown, and Auto Complete By Oum Saokosal Note: This tutorial is for ADT - Eclipse

1. 7.3. Alert Message, List,
Dropdown, and AutoComplete
Oum Saokosal
Master of Engineering in Information Systems, South Korea
855-12-252-752
oum_saokosal@yahoo.com

2. Agenda
• Alert Message
• List
• Dropdown
• AutoComplete

3. Alert Message
• There are 2 type of alert messages in Android:
1. Toast
2. AlertDialog
Toast AlertDialog

4. Toast
• Toast message is a simple way of showing an
alert which does not take your focus away:
appear and disappear automatically.
Toast.makeText(this,"Your Message",
Toast.LENGTH_LONG).show();
– this: refers to this activity the toast is displayed in.
– "Your Message": is where your write your message.
– Toast.LENGTH_LONG: To display a bit long.
– Toast.LENGTH_SHORT: To display a bit short.

5. AlertDialog
• AlertDialog is like a classic dialog box style, with a
button or two. But it is a bit tricky:
new AlertDialog.Builder(this)
.setTitle("Message Demo")
.setMessage("eek!")
.setNeutralButton("Close", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dlg, int sumthin) {
// do nothing – it will close on its own
}
}).show();

6. Example of AlertDialog
public class Main extends Activity implements OnClickListener{
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Button btn = new Button(this);
btn.setOnClickListener(this);
}
public void onClick(View v) {
new AlertDialog.Builder(this)
.setTitle("Alert Message")
.setMessage("Here is the message dialog box")
.setNeutralButton("Close", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
//To-do: nothing to do
}
}).show();
}
}

8. AlertDialog with 2 buttons
new AlertDialog.Builder(this)
.setTitle("Update Status")
.setMessage("Message")
.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
//Do something
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
// Do nothing.
}
}).show();

10. List
• To make a simple list, you can do it directly in Java
code:
public class Main extends ListActivity {
String[] items={"Cambodia", "Laos", "Thailand", "Vietnam"};
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
//setContentView(R.layout.main);
setListAdapter(new ArrayAdapter<String>(
this,
android.R.layout.simple_list_item_1,
items));
}

11. List with onListItemClick
• You can put an event to each item by override onListItemClick:
public class Main extends ListActivity {
String[] items={"Cambodia", "Laos", "Thailand", "Vietnam"};
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
//setContentView(R.layout.main);
setListAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, items));
}
public void onListItemClick(ListView parent, View v, int position,
long id) {
Toast.makeText(this, items[position], Toast.LENGTH_LONG).show();
}
}

13. Dropdown
• In Android, a dropdown selector is called
Spinner.

14. <?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/andro
id"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Select your country" />
<Spinner
android:id="@+id/spinner1"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>

15. public class Main extends Activity implements AdapterView.OnItemSelectedListener {
String[] items = {"Cambodia", "Laos", "Thailand", "Vietnam"};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Spinner spin = (Spinner) findViewById(R.id.spinner1);
spin.setOnItemSelectedListener(this);
ArrayAdapter<String> aa=new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item,
items);
aa.setDropDownViewResource(
android.R.layout.simple_spinner_dropdown_item);
spin.setAdapter(aa);
}
@Override
public void onItemSelected(AdapterView<?> parent, View v, int position,
long id) {
Toast.makeText(this, items[position], Toast.LENGTH_LONG).show();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
}

17. <?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:id="@+id/selection"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<AutoCompleteTextView android:id="@+id/edit"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:completionThreshold="3"/>
</LinearLayout>

18. AutoComplete
• Auto Complete text in Android is named
AutoCompleteTextView.

19. public class AutoComplete extends Activity implements TextWatcher {
TextView selection;
AutoCompleteTextView edit;
String[] items={"Cambodia", "Cambodian", "Khmer", "Phnom Penh",
"Siem Reap", "Preah Vihear", "Angkor Wat", "Angkor Thom"};
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
selection=(TextView)findViewById(R.id.selection);
edit=(AutoCompleteTextView)findViewById(R.id.edit);
edit.addTextChangedListener(this);
edit.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_dropdown_item_1line, items));
}
public void onTextChanged(CharSequence s, int start, int before, int count) {
selection.setText(edit.getText());
}
public void afterTextChanged(Editable s) {
}
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
}

21. Go on to the next slide