Android Introduction
GUI Menu
@2011 Mihail L. Sichitiu
1
Many thanks to Jun Bum Lim for his help
with this tutorial.
Goal

Create an application that supports
options/sub/context menus
Display
messages when
a menu clicked
Automatically
fill “Hi!”
in the EditText
Plus menu will
also open a
sub-menu
<option menu>
<sub-menu>
@2011 Mihail L. Sichitiu
<context menu>
2
Menu Composition
Hi
Sub1
Plus
Hola
Sub2
Home
Hello
<sub-menu>
Long press
in EditText
Pre
Next
<option menu>
<context menu from EditText>
@2011 Mihail L. Sichitiu
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Create HelloMenu Project




Create the two TextViews
and an EditText
Create “menu” folder in
res/
Create menu.xml in
res/menu/ (New > Other >
Android XML File)
Create context_menu.xml
in res/menu/
@2011 Mihail L. Sichitiu
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res/menu/menu.xml

Define Option menu and sub-menu
<?xml version="1.0" encoding="utf-8"?>
<menu
xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/menuItemPlus" android:title="@string/plus"
android:icon="@drawable/plus" >
Sub-menu items
<menu>
<item android:id="@+id/menuItemSub1" android:title="@string/sub1"></item>
<item android:id="@+id/menuItemSub2" android:title="@string/sub2"></item>
</menu>
</item>
<item android:icon="@drawable/home" android:id="@+id/menuItemHome"
android:title="@string/home"></item>
<item android:icon="@drawable/pre" android:id="@+id/menuItemPre"
android:title="@string/pre"></item>
<item android:icon="@drawable/next" android:id="@+id/menuItemNext"
android:title="@string/next"></item>
</menu>
Option menu items
@2011 Mihail L. Sichitiu
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res/menu/context.xml

Define context menu for EditText
<?xml version="1.0" encoding="utf-8"?>
<menu
xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/menuItemHi" android:title="@string/hi_msg"></item>
<item android:id="@+id/menuItemHola" android:title="@string/hola_msg"></item>
<item android:id="@+id/menuItemHello" android:title="@string/hello_msg"></item>
</menu>
@2011 Mihail L. Sichitiu
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res/values/strings.xml

Define constant strings used in the application
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Click Menu Button ! </string>
<string name="app_name">Android Menu Example</string>
<string
<string
<string
<string
name="plus">Plus</string>
name="pre">Pre</string>
name="next">Next</string>
name="home">Home</string>
<string name="sub1">Sub1</string>
<string name="sub2">Sub2</string>
<string name="hi_msg">Hi !</string>
<string name="hola_msg">Hola !</string>
<string name="hello_msg">Hello !</string>
</resources>
@2011 Mihail L. Sichitiu
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icons

Place icons used in menu.xml in res/drawable/
 Download icons at:
http://www4.ncsu.edu/~mlsichit/UCAB/resources.html
icons
@2011 Mihail L. Sichitiu
8
Inflating a option menu resource


Inflating a menu resource (menu.xml) by adding
onCreateOptionsMenu(Menu menu) in the main
Activity.
Menu items in menu.xml will appear when the
user touches the MENU button
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu, menu);
return true;
}
@2011 Mihail L. Sichitiu
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Response to user action

Response to menu click events by overriding
onOptionsItemSelected(Menu menu) in the
main Activity.
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menuItemPlus:
Toast.makeText(this, "Plus Button Clicked !", Toast.LENGTH_SHORT).show();
Log.i(TAG,"menuItemPlus");
return true;
:
:
case R.id.menuItemNext:
Toast.makeText(this, "Next Button Clicked !", Toast.LENGTH_SHORT).show();
Log.i(TAG,"menuItemNext");
return true;
}
return false;
}
@2011 Mihail L. Sichitiu
10
Register View for a context menu


By calling registerForContextMenu() and
passing it a View (an EditText in this example)
you assign it a context menu.
When this View (EditText) receives a long-press,
it displays a context menu.
public class AndroidMenuExampleActivity extends Activity {
private EditText mOutEditText;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mOutEditText = (EditText) findViewById(R.id.editText);
registerForContextMenu(mOutEditText);
}
:
:
@2011 Mihail L. Sichitiu
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Define context menu’s appearance

By overriding the activity's context menu create
callback method, onCreateContextMenu().
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.context_menu, menu);
}
@2011 Mihail L. Sichitiu
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Define context menu’s behavior

By overriding your activity's menu selection callback
method for context menu , onContextItemSelected().
@Override
public boolean onContextItemSelected(MenuItem item) {
Log.i(TAG,"ContextItem selected");
AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
switch (item.getItemId()) {
case R.id.menuItemHi:
mOutEditText.setText( this.getResources().getText(
R.string.hi_msg) );
return true;
case R.id.menuItemHola:
:
:
default:
return super.onContextItemSelected(item);
}
}
@2011 Mihail L. Sichitiu
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