Seven click modes of DataBinding onClick

Recently in the study of the use of DataBinding, encountered a lot of pits, record the following, to help the later study of DataBinding friends.

There is one ViewModel class, one xml, and xml is bound to ViewModel.

1. @{click}

//xml:
<Button
   android:layout_width="match_parent"
   android:layout_height="48dp"
   android:onClick="@{click}"
/>

//ViewModel:
public void click(View view){

}

2. No arguments: @ {()- > viewModel.click()}

//xml:
<Button
   android:layout_width="match_parent"
   android:layout_height="48dp"
   android:onClick="@{() -> viewModel.click()}"
/>

//ViewModel:
public void click(){

}

3. @{viewModel::click}

//xml:
<Button
   android:layout_width="match_parent"
   android:layout_height="48dp"
   android:onClick="@{viewModel::click}"
/>

//ViewModel:
public void click(View view){

}

tip: If the click method is set in other classes, such as EventHandlers. java, it is actually the same as the above 1

//xml:
<variable
  name="handler"
  type="com.xx.xxx.EventHandlers" />

<Button
   android:layout_width="match_parent"
   android:layout_height="48dp"
   android:onClick="@{handler::click}" />

// UI Class: Binding handler, Such as binding ViewModel That 
EventHandlers handler = new EventHandlers();
binding.setHandler(handler);

// EventHandlers  Execute click Events 
public void click(View view){
  //do
}

4. With parameters: @ {()- > viewModel.click(obj.id)}

//xml:
<variable
  name="viewModel"
  type="com.xx.xxx.ViewModel" />

<variable
  name="obj"
  type="com.xx.xxx.User" />
<Button
   android:layout_width="match_parent"
   android:layout_height="48dp"
   android:onClick="@{() -> viewModel.click(obj.id)}"
/>

//ViewModel:
public void click(long id){
   //do  
}

5. ObservableField < OnClickListener >

//xml:
 <variable
    name="iconView"
    type="com.xxxxx.IconView" />

 <RelativeLayout
    android:id="@+id/rl_icon_view"
    android:layout_width="match_parent"
    android:layout_height="55dp"
    android:onClick="@{iconView.clickListener}"
    >  

//IconView:
 public final ObservableField<OnClickListener> clickListener=new ObservableField<>();

//xml In Activity Class: 
 binding.iconView.clickListener.set(new View.OnClickListener() {
     @Override
     public void onClick(View v) {
       Toast.makeText(getApplicationContext(),"iconView",Toast.LENGTH_SHORT).show();
     }
 });

6. With parameters

 android:onClick="@{()->loadingModel.chooseLang(2)}"
 public void chooseLang(int language) {
    LogUtil.i(TAG, "language=" + language);

 }

7. Parameters with view

//xml:
<variable
    name="listener"
    type="test.carrie.todomvvmtest.ui.OnTaskItemListener"/>

android:onClick="@{(view)->listener.onCheckBoxClick(obj,view)}"


//adapter:
 public void onCheckBoxClick(ToDo entity, View v) {

    }

Summarize