public interface OnPagerStateListener {
void onPagerClosed();
void onPagerOpened();
}- 首先需要找到使用该Behavior的View
- 根据找到的View取得其使用的Behavior
- 通过获取的Behavior设置监听事件
<android.support.v4.widget.NestedScrollView
android:id="@+id/news_flow_nsv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fillViewport="true"
app:layout_behavior="@string/header_newsflow_behavior"> //此处使用了NewsFlowBehavior
<android.support.v7.widget.RecyclerView
android:id="@+id/news_flow_recyclerview"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</android.support.v4.widget.NestedScrollView>
NestedScrollView news_flow_nsv = findViewById(R.id.news_flow_nsv);
NewsFlowBehavior newsFlowBehavior = (NewsFlowBehavior) ((CoordinatorLayout.LayoutParams)news_flow_nsv.getLayoutParams()).getBehavior();
newsFlowBehavior.setOnPagerStateListener(new NewsFlowBehavior.OnPagerStateListener() {
@Override
public void onPagerClosed() {
newsFlowBehavior.setCouldScrollOpen(false);// 控制头部不能下拉显示出来
}
@Override
public void onPagerOpened() {
newsFlowBehavior.setCouldScrollOpen(true);// 控制头部可以下拉显示出来
}
});