Error using databinding in android

Question

I am trying to test data binding as given in the guide here. I have included this in my build.gradle file (of module app) :

compileSdkVersion 'android-MNC'
buildToolsVersion '23.0.0 rc2'

In the project build.gradle file, I have included this in my dependencies :

classpath "com.android.tools.build:gradle:1.3.0-beta2"
classpath "com.android.databinding:dataBinder:1.0-rc0"

The layout file is exactly the same as the one given in the guide.

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
   <variable name="user" type="com.example.User"/>
</data>
<LinearLayout
   android:orientation="vertical"
   android:layout_width="match_parent"
   android:layout_height="match_parent">
   <TextView android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="@{user.firstName}"/>
   <TextView android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="@{user.lastName}"/>
</LinearLayout>
</layout>

Initially it gave an error Element layout does not have the required attribute layout_width and layout_height.

I tried to fix it by assigning match_parent to both. Then I got the error Error parsing XML: duplicate attribute on the lines where i assigned layout_height and layout_width to the linear layout.

Again I tried to fix this by removing these attributes. Now every time I try to compile, I see this- error: package my.package.name.databinding does not exist.

The code completion is working perfectly in my Fragment where I am trying to use this layout.

So what did I miss ?

Answer 1

Your bindings in the xml file might be invalid.

Make sure to double check

1. Are type attributes valid reference to data object? type="my.package.Class"
2. Are the binding valid? name="client" -> "@{client.field}"
3. Are data fields accessible? public or encapsulated with getters
4. Are field names in java and the xml file matching, check for typos
5. If you have renamed the xml file, make sure you also update the Binding objects. OldNameBinding -> NewNameBinding
6. Clean Project

Answer 2

removing apply plugin: 'com.neenbedankt.android-apt' from my build.gradle solved my problem.

Answer 3

it’s usually because there is an error in your XML layout file and it can’t generate the binding object. Make sure you write data type correctly, check lower or upper of your writing.

    <data>
        <variable name="yourObject" type="com.example.simple.YourObject"/>
    </data>

And make sure object is right calling:

    <TextView android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@{yourObject.name}"/>
    <TextView