For basic buttons: On the button under properties choose the action tab. Then click 'Add'. For minimizing, maximising etc the actions are under the layout action type. Choose the action you want the button to do, then click OK.
If you want to hide or show something depending on what the user wants to see you can do that with triggers on sheet objects such as text boxes. Create a text box. Under Settings on the main Qlikview menu choose Variable Overview. Then click Add. Call the variable whatever you want to eg 'vTrigger'. In the text box properties, choose Actions, the Add, then under action type 'External' choose 'Set Variable'. You can then define the value you want the variable to have when the button is clicked. It doesn't have to be a number. In the chart that you want to show or hide in the Properties go to the 'Layout' tab. In the 'Show' box choose Conditional. If you have called the variable vTrigger and set the value as 1 when the button is clicked then the expression next to 'Conditional' should be vTrigger=1. This means that the chart will only show when the variable is 1 (i.e. when the button is clicked)
add a button and declare a variable (for example vShowChart), in the button go to action -> external -> set variable and set the variable vShowChart to 1, then go to the chart and under Properties -> Layout -> Show -> Conditional and then add $(vShowChart) = 1.
You can also use a container if you want to show/hide multiple charts.
As for the minimize, no need to do anything from the chart, you can from the button go to action -> layout -> Maximize object/Minimize object and there add the chart ID.
