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How to set a layout default value from parent layout using databinding and <include> tag in order to see it in preview?

I'm trying to use a view with databinding using the include tag multiple times.
It works great when the app runs, but in preview I don't manage to make it work in the parent.
Instead, I can do it on the view itself, but it implies that if I use it 5 times in the same layout, I'll have 5 exact copies. It's not a blocking issue, but for debugging/ UI, it makes things a bit more complicated.
Here's the code of the replicated view:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<data>
<import type="android.view.View"/>
<import type="android.text.TextUtils"/>
<variable
name="title"
type="String" />
<variable
name="value"
type="String" />
</data>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/white"
android:text="#{(!TextUtils.isEmpty(title) ? title : `Title`).concat(`:`), default=`Title:`}" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#{!TextUtils.isEmpty(value) ? #color/darkBlue : #color/red, default=#color/red }"
android:text="#{(!TextUtils.isEmpty(value) ? value : `Unknown`), default=`Unknown`}" />
</LinearLayout>
</layout>
And here's how it's included:
<include layout="#layout/titled_entry"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
bind:title="#{`Firstname`}"
bind:value="#{user.firstName}" />
In Android it looks like this
But in preview it looks like this
Does anyone know how to fix it ?
Thanks, and have a good day in those complicated times.

Store your string in string.xml
And set that as default value
Like below
android:text='#{viewModel.firstName, default=#string/firstName}`

Android - Make new view attribute and pass to its children in XML compound view component - data binding in layout

Full answer:
1. Enable data binding in app/build.gradle:
dataBinding {
enabled true
}
2. Use DataBindingUtil to set content view
java
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DataBindingUtil.setContentView(this, R.layout.activity_engineering_mode_main);
}
3. Child item layout
You will see that I define 2 new attributes
values/bools.xml
<variable
name="textTitle"
type="String" />
<variable
name="buttonVisibility"
type="boolean" />
With textTitle, you can use any string from resource by #string/string_name
With buttonVisibility, you have to define bool resource type, and use #bool/bool_name
layout/item_engineering_list_row.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<import type="android.view.View" />
<variable
name="textTitle"
type="String" />
<variable
name="buttonVisibility"
type="boolean" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="#dimen/engineer_actionbar_height"
android:background="#color/engineer_background_color"
android:orientation="horizontal">
<TextView
android:id="#+id/engineer_txtName"
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_marginLeft="#dimen/engineer_text_margin"
android:layout_weight="1"
android:gravity="center_vertical"
android:text="#{textTitle}"
android:textColor="#color/engineer_text_color"
android:textSize="#dimen/engineer_title_font_size" />
<Button
android:id="#+id/engineer_btnNext"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_marginRight="#dimen/engineer_text_margin"
android:text="BACK"
android:visibility="#{buttonVisibility ? View.VISIBLE : View.GONE, default=gone}" />
</LinearLayout>
</layout>
4. Boolean resource file
<?xml version="1.0" encoding="utf-8"?>
<resources>
<bool name="item_button_visibility_default">false</bool>
<bool name="item_button_visibility_on">true</bool>
<bool name="item_button_visibility_off">false</bool>
</resources>
5. Parent layout, which includes some children and passes value to new attributes
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include
android:id="#+id/includedLayout0"
layout="#layout/item_engineering_list_row"
app:buttonVisibility="#{#bool/item_button_visibility_on}"
app:textTitle="#{#string/app_name}" />
<include
android:id="#+id/includedLayout1"
layout="#layout/item_engineering_list_row"
app:buttonVisibility="#{#bool/item_button_visibility_default}"
app:textTitle="#{#string/app_name}" />
</LinearLayout>
</layout>
Original Question:
I am new to android and I've been working with QML in QT for a time.
I wonder how I can make a layout more easier by applying params in XML in compound view components.
I have a custom layout item in xml and want to pass some attributes from a parent to its children, and I also want to initialize parent's attribute with new values to customize its children too.
My concept is as below:
item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
!!!! how to declare a new attribute here !!!
| like this:
| textTitle="New Title" // default value for child
| buttonVisibility="visible" // default value for child
">
<TextView
android:id="#+id/engineer_txtTitle"
android:text= textTitle <--- use parent's />
<Button
android:id="#+id/engineer_btnBack"
android:visibility= buttonVisibility <== use parent's />
</LinearLayout>
CLICK HERE TO SEE IMAGE: base Item
main.xml
<LinearLayout>
<include
android:id="#+id/item1"
layout="#layout/item"
textTitle= "FIRST"
// buttonVisibility not set here, use default as visible
/>
<include
android:id="#+id/item2"
layout="#layout/item"
textTitle= "SECOND"
buttonVisibility = "gone" // dont show button
/>
</LinearLayout>
CLICK HERE TO SEE IMAGE: apply with param

You can use Data Binding of Architecture component. Here is an sample of your requirement.
Recently I answered a question related to this.
Clean answer
This example shows pass value to <include.
I have a common view layout_common.xml, I want to pass String to included layout. I will create a variable of type String. Refer that String to your TextView. I created passedText for example.
<?xml version="1.0" encoding="utf-8"?>
<layout
xmlns:android="http://schemas.android.com/apk/res/android"
>
<data>
// declare fields
<variable
name="passedText"
type="String"/>
</data>
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#{passedText}"/> //set field to your view.
</layout>
Now you can pass passedText field to your <include tag.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<layout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<include
android:id="#+id/includedLayout"
layout="#layout/layout_common"
app:passedText="#{#string/app_name}" // here we pass any String
/>
</LinearLayout>
</layout>
Note that both layouts (parent & included) should be binding layout, i.e. wrapped with <layout> and </layout> tags

Thanks #Khemraj to show the keyword "Data Binding" in Android :)
I have found the answer for me. It includes Khemraj's answer and some small code added to values resource.
I posted it in my question for others to find it easily.

Android: re-using layouts using include with parameters

I'm creating an ordered list with a custom styling which is used in multiple places. I try to avoid extra code and to create a re-usable layout file for the list item, which can be included to ordered list with certain parameters. How I could do that?
What I have now is following:
layout_ordered_list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<variable
name="order"
type="java.lang.String" />
<variable
name="text"
type="java.lang.String" />
</data>
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/order"
android:layout_width="28dp"
android:layout_height="28dp"
android:layout_marginBottom="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:gravity="center"
android:text="#{order}"
android:textAlignment="center"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="60dp"
android:text="#{text}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
</layout>
Then I would like to use that layout like following:
layout_ordered_list.xml
<LinearLayout>
<include layout="#layout/layout_ordered_list_item"
bind:order="1"
bind:text="First text content"/>
<include layout="#layout/layout_ordered_list_item"
bind:order="2"
bind:text="Second text content"/>
etc.
</LinearLayout>
Note that I'm not interested about setting variables in code dynamically. I use these layouts only with hard-coded values (or with string resources) like in my example. But since I'm using these so many times, I don't want to copy-paste list item again and again just to alter order and text content. I also know that my example is not working, it's here just to demonstrate how I would like it to work.
I've already searched the answer from Android documents but there is no example like that.
https://developer.android.com/training/improving-layouts/reusing-layouts.html
https://developer.android.com/topic/libraries/data-binding/index.html#includes
Pretty much identical question has been also asked before in SO but there is no usable answer either: How to Re-using Layouts with <include/> with parameters?

You should be able to achieve what you want by using the databinding library to inflate the including layout, and then passing in the hard coded text using a databinding statement.
Details on the databinding expression language can be found here.
<layout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:bind="http://schemas.android.com/apk/res-auto">
<LinearLayout>
<include layout="#layout/layout_ordered_list_item"
bind:order="#{`1`}"
bind:text="#{`First text content`}"/>
<include layout="#layout/layout_ordered_list_item"
bind:order="#{`2`}"
bind:text="#{`Second text content`}"/>
</LinearLayout>
</layout>

NextFocus editText in include layout

I create a simple layout containing my label and my editText. This layout is included several time to create a form.
But with this method the "nextFocus" function doesn't work properly and I can't find a solution. I need to give the id of the next editText but because it's inside a include layout, the id is the same as the current editText.
Is their a way to achieve this by using only xml solution? I particulary think of databinding.
This is my layout's :
The include layout :
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewModel"
type="viewModels.StringDataTypeViewModel"/>
<variable
name="nextFocus"
type="Integer"/>
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp"
android:orientation="horizontal"
android:gravity="center_vertical">
<TextView
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
tools:text="Nom de famille : "
android:text="#{viewModel.label}"
android:singleLine="true"
android:ellipsize="end"/>
<EditText android:id="#+id/value"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:textSize="#dimen/patient_detail_edittext_text_size"
android:inputType="textPersonName"
android:ellipsize="end"
tools:text="Dupont"
android:text="#={viewModel.value}"
android:textColor="#android:color/widget_edittext_dark"
android:clickable="#{viewModel.editable}"
android:cursorVisible="#{viewModel.editable}"
android:focusable="#{viewModel.editable}"
android:focusableInTouchMode="#{viewModel.editable}"
android:background="#{viewModel.editable ? #android:drawable/edit_text : #drawable/empty_drawable}"
android:nextFocusForward="#id/value"/>
</LinearLayout>
The form layout :
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:visibility="#{viewModel.editable ? View.VISIBLE: View.GONE}">
<include layout="#layout/string_data_type_layout"
app:viewModel="#{viewModel.familyNameViewModel}" />
<include layout="#layout/string_data_type_layout"
app:viewModel="#{viewModel.givenNameViewModel}" />
<include layout="#layout/string_data_type_layout"
app:viewModel="#{viewModel.patientCodeViewModel}" />
<include layout="#layout/string_data_type_layout"
app:viewModel="#{viewModel.addressViewModel}" />
</LinearLayout>

Step 1: Give unique ids to all your include elements
<include android:id="#+id/edit_text_1"
... />
<include android:id="#+id/edit_text_2"
... />
Step 2: Add these attributes to the root of your included layout xml (LinearLayout in your case)
<LinearLayout
android:descendantFocusability="afterDescendants"
android:focusableInTouchMode="true"
... />
Step 3: Use the ids defined in step 1 in all your include elements (as per required navigation)
<include android:id="#+id/edit_text_1"
app:nextFocus="#{#id/edit_text_2}"
... />
Cheers!

Can you try to change the id of EditText?
This is work for me:
1.The include Layout:
<layout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools">
...
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
...>
...
<EditText android:id="#+id/et_common"
.../>
</LinearLayout>
2.Create an id in ids.xml
<item name="next_focus_et" type="id"/>
3.Set next focus on another view
<Button
android:id="#+id/btn"
android:nextFocusUp="#id/next_focus_et"
.../>
4.Change the id of EidtText to "next_focus_et" in the code.
private void initComplexNextFocus(){
mBinding.includeStaticDns2Edit.et_common.setId(R.id.next_focus_et);
}

How to bind layout with several qualifiers

I have 2 layouts: one for v19+ and another for earlier versions. They contain different views with different ids. How can I say Android DataBinding framework that I want to work with both layouts? It generates views only for one layout (selects randomly).
layout/temp_view.xml :
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="block"
type="ru.temp.model.content.blocks.WebMediaBlock" />
<import type="ru.temp.model.Types.ProviderTypes" />
</data>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
tools:background="#android:color/white">
<ImageView
android:id="#+id/provider"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:paddingTop="#dimen/size5"
android:src="#{ProviderTypes.fromString(block.provider).getResId()}" />
</FrameLayout>
</layout>
layout-v19/temp_view.xml :
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="block"
type="ru.temp.model.content.blocks.WebMediaBlock" />
<import type="ru.temp.model.Types.ProviderTypes" />
</data>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
tools:background="#android:color/white">
<ru.temp.utils.EmbedView
android:id="#+id/media_embed"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<ru.temp.structure.static_material.CreditsView
android:id="#+id/credits_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</FrameLayout>
</layout>
Update:
Finally I've found out the root of the problem. I don't know why but it does not generate *BindingImpl files when use minSdkVersion 21. If specify earlier versions it works as said #yigit

Data binding will generate a base class that serves as a common interface for both (the variables). Data binding will take care of creating the right instance when you call DataBindingUtil.setContentView(activity, R.layout.tmp_view).
For instance, in your example, it will generate
TempViewBinding, TempViewBindingImpl and TempViewBindingV19Impl.
You can check these classes inside <app module>/build/intermediates/classes/<your package>/databinding/ after you compile.
TempViewBinding is the base class and it will have the combination of variables and views for each layout.
If you are not seeing them in the IDE, might be an auto-completion bug in AS (please file a bug).