[android] How to programmatically set the layout_align_parent_right attribute of a Button in Relative Layout?

I have a relative layout which I am creating programmatically:

 RelativeLayout layout = new RelativeLayout( this );
    RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.FILL_PARENT,
            LayoutParams.WRAP_CONTENT);

Now I have two buttons which I want to add in this relative layout. But the problem is both buttons are being shown on the left of the RelatiiveLayout overlapping on each other.

buttonContainer.addView(btn1);
buttonContainer.addView(btn2);

Now I want to know how can I programmatically set the the android:layout_alignParentRight="true" or android:layout_toLeftOf="@id/btn" attribute of buttons as we do in the xml?

1. you need to create and id for the buttons you need to refference: btn1.setId(1);
2. you can use the params variable to add parameters to your layout, i think the method is addRule(), check out the android java docs for this LayoutParams object.

For adding a RelativeLayout attribute whose value is true or false use 0 for false and RelativeLayout.TRUE for true:

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) button.getLayoutParams()
params.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE)

It doesn't matter whether or not the attribute was already added, you still use addRule(verb, subject) to enable/disable it. However, post-API 17 you can use removeRule(verb) which is just a shortcut for addRule(verb, 0).

Kotlin version:

Use these extensions with infix functions that simplify later calls

infix fun View.below(view: View) {
    (this.layoutParams as? RelativeLayout.LayoutParams)?.addRule(RelativeLayout.BELOW, view.id)
}

infix fun View.leftOf(view: View) {
    (this.layoutParams as? RelativeLayout.LayoutParams)?.addRule(RelativeLayout.LEFT_OF, view.id)
}

infix fun View.alightParentRightIs(aligned: Boolean) {
    val layoutParams = this.layoutParams as? RelativeLayout.LayoutParams
    if (aligned) {
        (this.layoutParams as? RelativeLayout.LayoutParams)?.addRule(RelativeLayout.ALIGN_PARENT_RIGHT)
    } else {
        (this.layoutParams as? RelativeLayout.LayoutParams)?.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, 0)
    }
    this.layoutParams = layoutParams
}

Then use them as infix functions calls:

view1 below view2
view1 leftOf view2
view1 alightParentRightIs true

Or you can use them as normal functions:

view1.below(view2)
view1.leftOf(view2)
view1.alightParentRightIs(true)