How to place a button "swap file displays" in custom toolbar

Please let me question.sorry my poor English. ...
I want to assign a "swap file display" button to custom toolbar,as a button.

a "swap file display" button of default in a above picture,i
t is too little to push easily.

Please teach me.DOpus is BEST ! :laughing:
thank you.ansewerer who always give me advice,thank you :smiley:

The button-code is just: GO SWAP

Thank you for teaching.

My DOpus has kept more convenient.
I feel like doing a string of questions.
Thank you :laughing: