@Override
public boolean onCreateOptionsMenu(com.actionbarsherlock.view.Menu menu) {
    getSupportMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override
 public boolean onCreateOptionsMenu(Menu menu) {
       return false;
 }

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    MenuItem item= menu.findItem(R.id.action_settings);
    item.setVisible(false);
    return true;
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    return false;
}

<item
    android:id="@+id/action_settings"
    android:orderInCategory="100"
    android:showAsAction="never"
    android:title="@string/action_settings"/>

@Override
public void onCreate(Bundle savedInstanceState) {
    getApplicationInfo().targetSdkVersion = 10; // To enable the 3-dot menu call this code before super.OnCreate
    super.onCreate(savedInstanceState);
}

@Override
public void onCreate(Bundle savedInstanceState) {
    getApplicationInfo().targetSdkVersion = 14; // To disable the 3-dot menu call this code before super.OnCreate
    super.onCreate(savedInstanceState);
}

@Override
public boolean onCreateOptionsMenu(Menu menu)
{
    //Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_planos, menu);
    return true;
}

<item
    android:id="@+id/action_settings"
    android:orderInCategory="100"
    android:showAsAction="never"
    visibility=false
    android:title="@string/action_settings"/>

<item
    android:id="@+id/linearlayout_splash"
    android:orderInCategory="100"
    android:showAsAction="never"
    android:visible="false"
    android:title="@string/action_settings"/>

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

Menu overflow;

 @Override
public boolean onCreateOptionsMenu(Menu menu) {

    getMenuInflater().inflate(R.menu.mymenu, menu);
    this.overflow = menu;
    return super.onCreateOptionsMenu(menu);
}

public void hideorShowMenuItems(boolean bool){
   overflow.getItem(1).setVisible(bool);
   overflow.getItem(2).setVisible(bool);
   overflow.getItem(3).setVisible(bool);
   overflow.getItem(4).setVisible(bool);
   overflow.getItem(5).setVisible(bool);
}

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/action_settings"
        android:orderInCategory="100"
        android:visible="false"
        android:title="@string/action_settings"
        app:showAsAction="never" />
</menu>

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    // if nav drawer is opened, hide the action items
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(leftDrawer);
    return (!drawerOpen);
}

@Override
public boolean onKeyDown(int keycode, KeyEvent event ) {
    //KEYCODE_MENU
 if(keycode == KeyEvent.KEYCODE_MENU){
 /* AlertDialog.Builder dialogBuilder
  = new AlertDialog.Builder(this)
  .setMessage("Test")
  .setTitle("Menu dialog");
  dialogBuilder.create().show();*/
  return true;

//  finish();
 }
 return super.onKeyDown(keycode,event);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

<menu xmlns:android="http://schemas.android.com/apk/res/android" ></menu>

<style name="AppTheme" parent="Theme.AppCompat.Light">
    ...
    <item name="android:actionOverflowButtonStyle">@style/AppTheme.Overflow</item>
    <!-- If you're using AppCompat, instead use -->
    <item name="actionOverflowButtonStyle">@style/AppTheme.Overflow</item>
</style>

<style name="AppTheme" />
<style name="AppTheme.Overflow">
    <item name="android:src">@null</item>
</style>

<activity android:name=".NoOverflowActivity"
          android:theme="@style/AppTheme.NoOverflow" >

for hiding 3 dots in actionbar/ toolbar

 public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_dash_board_drawer, menu);
        return false;  //for visible 3 dots change to true, hiding false
    }