How to set Id of dynamic created layout?

You create an ids.xml file and place all your required ids in it as below

<?xml version="1.0" encoding="utf-8"?>
<resources>
        <item type="id" name="layout1" />
        <item type="id" name="layout2" />
        <item type="id" name="layout3" />
</resources>

Now for your dynamically created layouts or views you can use these ids as below

new_layout1.setId(R.id.layout1);
new_view2.setId(R.id.layout2);
new_layout3.setId(R.id.layout3);

I hope it may help you.

Google finally realized the need of generating unique IDs for programmatically created views...

From API level 17 and above, one can use View.generateViewId() like this:

view.setId(View.generateViewId());

For apps targeting API level 16 or lower, use ViewCompat.generateViewId() instead:

view.setId(ViewCompat.generateViewId());

create folder res/values/ids.xmland

<?xml version="1.0" encoding="utf-8"?>

<resources>   
   <item name="refresh" type="id"/>   
   <item name="settings" type="id"/>        
</resources>

in Activity class call like this

ImageView refreshImg = new ImageView(activity);
ImageView settingsImg = new ImageView(activity); 

     refreshImg.setId(R.id.refresh);
     settingsImg .setId(R.id.settings);

This wont work:

layout.setId(100);

But, this will:

int id=100;
layout.setId(id);

also, this one too (credit: Aaron Dougherty):

layout.setId(100+1);

For compatibility purposes use: ViewCompat.generateViewId()