Action Button with no padding example.

ActionButton.java

package com.example.actionbutton;

import android.annotation.SuppressLint;
import android.content.Context;
import android.util.AttributeSet;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;
import android.widget.Toast;


public class ActionButton extends ImageView
{
	@SuppressLint("InlinedApi")
	public static final int ATTR_STYLE = android.R.attr.actionButtonStyle;
	
	private Menu mMenu;
	private MenuItem mMenuItem;
	
	
	public ActionButton(Context context)
	{
		this(context, null);
	}
	
	public ActionButton(Context context, AttributeSet attrs)
	{
		this(context, null, ATTR_STYLE);
	}
	
	public ActionButton(Context context, AttributeSet attrs, int defStyle)
	{
		super(context, attrs, defStyle);
		setOnClickListener(mOnClick);
		setOnLongClickListener(mOnLongClick);
		// These override the default values in the actionButtonStyle style.
		setMinimumWidth(0);
		setPadding(0, 0, 0, 0);
	}
	
	public void setMenuData(Menu menu, int id)
	{
		mMenu     = menu;
		mMenuItem = menu.findItem(id);
		setId(id);
		setImageDrawable(mMenuItem.getIcon());
		setContentDescription(mMenuItem.getTitle());
	}
	
	private View.OnClickListener mOnClick = new View.OnClickListener()
	{
		@Override
		public void onClick(View v)
		{
			mMenu.performIdentifierAction(mMenuItem.getItemId(), 0);
		}
	};
	
	private View.OnLongClickListener mOnLongClick = new View.OnLongClickListener()
	{
		@Override
		public boolean onLongClick(View v)
		{
			Toast.makeText(v.getContext(), mMenuItem.getTitle(), Toast.LENGTH_SHORT).show();
			return false;
		}
	};
}

main.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android" >
	
	<item
		android:id="@+id/action_share"
		android:showAsAction="ifRoom"
		android:icon="@android:drawable/ic_menu_share"
		android:title="@string/action_share"
		android:actionViewClass="com.example.actionbutton.ActionButton"
		/>
	
</menu>

MainActivity.java

package com.example.actionbutton;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;


public class MainActivity extends Activity
{
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
	}
	
	@Override
	public boolean onCreateOptionsMenu(Menu menu)
	{
		getMenuInflater().inflate(R.menu.main, menu);
		((ActionButton)menu.findItem(R.id.action_share)
			.getActionView()).setMenuData(menu, R.id.action_share);
		return true;
	}
	
	@Override
	public boolean onOptionsItemSelected(MenuItem item)
	{
		if(item.getItemId() == R.id.action_share){
			Toast.makeText(this, "Got a click", Toast.LENGTH_SHORT).show();
			return true;
		}
		return super.onOptionsItemSelected(item);
	}
}