data binding - Android dataBinding - How to get resource id of a View in xml -

in android studio data binding works , set fine. have boolean defined this:

<resources>     <bool name="showads">false</bool> </resources> 

and in layout.xml file referenced boolean (which works fine) want assign id based on boolean. let me show trying accomplish:

i have button in relativelayout tag , depending on boolean reposition button. have this:

<button    android:id="@+id/startbutton"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:textsize="64dip"    ****************    android:layout_below="@{@bool/showads ? @+id/adone : @+id/title_main}"    ****************    android:layout_centerhorizontal="true"    android:textcolor="#0080ff"    android:text="@string/start_btn_title" /> 

see want to do? want layout button below layout called adone if showads boolean true, otherwise place below layout called title_main. whats syntax have here not compiling. compile error:

expression expected after second @ sign

the above same problem in how dimensions dimens.xml

none of layoutparams attributes have built-in support. answered in linked article, data binding of layoutparams thought easy abuse left out of built-in bindingadapters. not abusing it, should add own.

@bindingadapter("android:layout_below") public static void setlayoutbelow(view view, int oldtargetid, int newtargetid) {     relativelayout.layoutparams layoutparams = (relativelayout.layoutparams)         view.getlayoutparams();     if (oldtargetid != 0) {         // remove previous rule         layoutparams.removerule(relativelayout.below);     }     if (newtargetid != 0) {         // add new rule         layoutparams.addrule(relativelayout.below, newtargetid);     }     view.setlayoutparams(layoutparams); } 

as aside, @+id/adone in binding syntax not create id. should create id in view you're binding to.