How to set RelativeLayout layout params in code not in xml?

Question

For example I want to add 3 buttons on screen: one align left, one align center, last one align right.

How can I set their layout in code, not in xml?

Answer 1

Just a basic example:

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
Button button1;
button1.setLayoutParams(params);

params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.RIGHT_OF, button1.getId());
Button button2;
button2.setLayoutParams(params);

As you can see, this is what you have to do:

1. Create a RelativeLayout.LayoutParams object.
2. Use addRule(int) or addRule(int, int) to set the rules. The first method is used to add rules that don't require values.
3. Set the parameters to the view (in this case, to each button).