If you would like to change the TextColor of a Toast, you can reference this question, as it has a good example.
To do this on an action bar item, you'll first need to add a custom view to your action bar since it doesn't support a way to handle long clicks.
I would create a layout file used for your action bar, and then inside your activities onCreate() you can do this:
View actionBarView = getLayoutInflater().inflate(R.layout.my_action_bar, null)
ImageView actionItem = (ImageView) actionBarView.findViewById(R.id.myImageViewIcon);
actionItem.setOnLongClickListener(new OnLongClickListener(){
@Override
public boolean onLongClick(View v){
// Show toast with custom text
}
});
actionItem.setOnClickListener(new OnClickListener(){
@Override
public boolean onClick(View v){
// Handle regular click
}
});
getSupportActionBar().setCustomView(actionBarView);
For more information on the second part, You can reference this question.