How to start an activity from a button click
<p>Can you help me with code please?
I have 4 activities : Activity1 Activity2 Activity3 and Activity4
and in Main Menu I have 4 buttons : button1 button2 button3 and button4.</p>

<p>goal: </p>

<ul>
<li>When I click on button1 - activity1 starts.</li>
<li>When I click on button2 - activity2 starts.</li>
<li>When I click on button3 - activity3 starts.</li>
<li>When I click on button4 - activity4 starts.</li>
</ul>

<p>Can anyone help me with code please? It's hard for me :|</p>
