Data Binding with srcCompat

Question

I'm using the new vector drawable support in Support Lib v23.2 with app:srcCompat & trying to set its drawable via data binding.

<layout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:app="http://schemas.android.com/apk/res-auto">  <data>     <variable         name="mediaPojo"         type="in.ishaan.pika.data_binding.MediaPojo"/> </data>  <RelativeLayout     android:background="@color/black"     android:layout_width="match_parent"     android:layout_height="match_parent">      <VideoView         ... />      <ImageView         ...         app:srcCompat="@{mediaPojo.isPlaying ? @drawable/ic_pause_24dp : @drawable/ic_play_arrow_24dp}"     />      <ProgressBar         .../> </RelativeLayout> </layout> 

On trying to build, studio throws:

Error:(33, 30) Cannot find the setter for attribute 'app:srcCompat' with parameter type android.graphics.drawable.Drawable.

Answer 1

You can simply use android:src attribute instead compat attribute when you set vector resource by DataBinding.

DataBinding library generates class that execute setImageResource method at runtime.

<ImageView         ...         android:src="@{@drawable/your_drawable}" /> 

According to http://android-developers.blogspot.com/2016/02/android-support-library-232.html setImageResource method can be used at runtime on older system versions without any additional changes.

If you would like to use app:srcCompat attribute. You must define @BindingMethods annotation which connects attribute with appropriate setter from ImageView. For example in your Activity or Fragment add.

@BindingMethods({     @BindingMethod(type = android.widget.ImageView.class,             attribute = "app:srcCompat",             method = "setImageDrawable") }) public class MainActivity extends AppCompatActivity {    // your activity body here  } 

Answer 2

You may have to resort to using a binding adapter with a method signature similar to the following:

@BindingAdapter("app:srcCompat") public static void bindSrcCompat(ImageView imageView, Drawable drawable){     // Your setter code goes here, like setDrawable or similar } 

Here is the reference: http://developer.android.com/reference/android/databinding/BindingAdapter.html