Kotlin in xml onClick not work

问题

I learning kotlin, and now for me not cearly some moment. I have xml

<ImageView
                    android:id="@+id/aries"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="10dp"
                    android:tag="1"
                    android:onClick="clickItemHoro"
                    android:src="@drawable/aries" />

and fragment

class ChooseYourHoroscope : Fragment(){

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        val view = inflater.inflate(R.layout.fragment_welcome_old, container, false)

        return view;
    }

    fun clickItemHoro(v: View?){
        Log.e("clickItemHoro", v!!.tag.toString())
    }

}

when i click button i have error:

Could not find method clickItemHoro(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatImageView with id 'aries'

why it happen? Code vary simple, but it not work, i cant understand why

回答1:

Try to use Kotlin Extensions plugin, it should work.

in build.gradle (app) add apply plugin: 'kotlin-android-extensions'

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'

then import it in MainActivity.kt

import kotlinx.android.synthetic.main.activity_main.*

回答2:

apply plugin: 'kotlin-android-extensions' must use kotlin extenstion Then it will work

回答3:

As mentioned above it's a good idea to add the Kotlin extensions, additionally you could set an onClickListener on the ImageView directly in your code instead of declaring the method in your xml files: onClick:

aries.setOnClickListener { doSomething() }

回答4:

In Gradle file add

apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'

then activity add

   import kotlinx.android.synthetic.main.activity_main.*

回答5:

Based on the above answers and comments posting the full solution here so that it would be helpful for others.

First remove android:onClick attribute from the xml code of ImageView.

Then change the fragment code as below:

class ChooseYourHoroscope : Fragment(){
  override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                          savedInstanceState: Bundle?): View? {
      val view = inflater.inflate(R.layout.fragment_welcome_old, container, false)
      val aries = view.findViewById<ImageView>(R.id.aries)
      aries.setOnClickListener{
          //Write ur action here
      }

      return view;
   }
}

来源：https://stackoverflow.com/questions/40885426/kotlin-in-xml-onclick-not-work

标签

android

click

fragment

kotlin