问题
I have a weird "problem" or may be it's a "feature" and I just don't know, whenever a NativeAdExpress is loaded in my RecyclerView if only part of the NativeAd is visible, it forces the RecyclerView to scroll until the Native ad becomes fully visible, this behavior causes the list to keep jumping as I scroll.
My Layout is mainly:
Activity > AppBar with Tabs and ViewPager > each Page in the Pager contains PullToRefresh and inside it there's a RecyclerView, The RecyclerView has 2 types of items (Article and NativeAdExpress).
UPDATE: My guess on why this is happening is mainly because native ads express render in a webview, and this webview receives focus then this causes the RecyclerView to scroll to it, but that's only a Guess
UPDATE 2: Apparently this is an issue in Support Lib. 24.0.0, that's the cost of being too up2date :(
Heres's my Full XML/Layouts
<?xml version="1.0" encoding="utf-8"?>
<my.package.custom.views.CustomDrawerLayout
android:id="@+id/drawer_layout"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:openDrawer="end">
<include
layout="@layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<android.support.design.widget.NavigationView
android:id="@+id/nav_view"
style="@style/AlertDialog.AppCompat.Light"
fontPath="fonts/fonts/DroidKufi-Regular.ttf"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="end"
android:fitsSystemWindows="true"
app:elevation="5px"
app:headerLayout="@layout/nav_header"
app:itemIconTint="@color/colorPrimary"
app:itemTextColor="@color/contentColor"
app:actionLayout="@layout/nav_item_layout"
app:menu="@menu/drawer_menu"
app:theme="@style/NavDrawerStyle"
tools:openDrawer="end"
/>
</my.package.custom.views.CustomDrawerLayout>
where "app_bar_main.xml" is as follows:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context=".ui.activities.ArticlesListActivity">
<android.support.design.widget.AppBarLayout
android:id="@+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="end">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="52dp"
android:background="?attr/colorPrimary"
android:gravity="end"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal"
android:paddingEnd="14dp"
android:paddingStart="14dp">
<android.support.v7.widget.AppCompatImageButton
android:id="@+id/ivCustomDrawable"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:background="@color/transparent"
android:tint="@color/white"
/>
<TextView
android:id="@+id/view_title"
android:visibility="gone"
style="@style/SectionTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
/>
<android.support.v7.widget.AppCompatSpinner
android:id="@+id/sources_spinner"
android:gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:transitionName="@string/transition_splash_logo"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
tools:targetApi="lollipop"/>
</RelativeLayout>
</android.support.v7.widget.Toolbar>
<android.support.design.widget.TabLayout
android:id="@+id/tabs"
style="@style/TabsStyle"
android:layout_width="match_parent"
android:layout_height="42dp"
android:layout_gravity="bottom"
android:layout_marginTop="0dp"
android:transitionGroup="true"
app:tabContentStart="0dp"
app:tabGravity="fill"
app:tabIndicatorColor="@color/white"
app:tabIndicatorHeight="3dp"
app:tabMode="scrollable"
app:tabPaddingBottom="0dp"
app:tabPaddingTop="0dp"
app:tabTextAppearance="@style/TextAppearance.RegularTextFont"
/>
</android.support.design.widget.AppBarLayout>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context=".ui.activities.ArticlesListActivity"
tools:showIn="@layout/activity_newsitem_list">
<android.support.v4.view.ViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</RelativeLayout>
</android.support.design.widget.CoordinatorLayout>
and finally I have 2 View Types Item and NativeAdExpress:
The NativeAdExpress ViewHolder is as follows:
public class NativeExpressAdViewHolder extends BaseCardAdViewHolder {
private final NativeExpressAdView view;
private boolean loaded = false;
private AdListener adListener;
private WeakReference<Context> context;
public NativeExpressAdViewHolder(View itemView, String adId, Context context) {
super(itemView);
view = new NativeExpressAdView(context);
view.setAdUnitId(adId);
((LinearLayout) itemView.findViewById(R.id.express_ad_holder)).addView(view);
this.context = new WeakReference<>(context);
}
public void loadAd(float cardWidthInDips) {
if (!loaded && null != context.get() && !view.isLoading()) {
int width = cardWidthInDips > 0 ? (int) cardWidthInDips : 330;
if (view.getAdSize() == null) {
view.setAdSize(new AdSize(width, 330));
view.setAdListener(new AdListener() {
@Override
public void onAdLoaded() {
super.onAdLoaded();
loaded = true;
if (adListener != null) {
adListener.onAdLoaded();
}
}
@Override
public void onAdFailedToLoad(int i) {
super.onAdFailedToLoad(i);
if (adListener != null) {
adListener.onAdFailedToLoad(i);
}
}
@Override
public void onAdOpened() {
super.onAdOpened();
if (adListener != null) {
adListener.onAdOpened();
}
}
});
}
new Handler(context.get().getMainLooper()).post(new Runnable() {
@Override
public void run() {
view.loadAd(new AdRequest.Builder().build());
}
});
}
}
public NativeExpressAdView getView() {
return view;
}
public void setAdListener(AdListener adListener) {
this.adListener = adListener;
}
@Override
public void destroyAd() {
if (view != null) {
view.destroy();
loaded = false;
}
}
}
and ads are create using a custom adapter as follows:
private BaseCardViewHolder createNativeExpressAdViewHolder(ViewGroup parent) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.ad_express, parent, false);
final NativeExpressAdViewHolder viewHolder = new NativeExpressAdViewHolder(
view,
adManager.getNativeExpressAdId(),
context.get()
);
adViewHolders.add(viewHolder);
viewHolder.setAdListener(new AdListener() {
@Override
public void onAdFailedToLoad(int errorCode) {
Log.i("ADS", "onAdFailedToLoad " + errorCode);
}
@Override
public void onAdLoaded() {
super.onAdLoaded();
// Do something
}
});
viewHolder.loadAd(cardWidthInDips);
return viewHolder;
}
回答1:
I did not understand where you actually implement a RecyclerView in your code but here is anyway maybe something that could work in your case.
I had a similar problem with a GridView always getting the focus during a Fragment first load, it was also automatically scrolling down straight to the GridView.
After a lot of tests, I finally stopped this behavior with this one line on the parent layout of the GridView:
android:descendantFocusability="blocksDescendants"
This line basically means that all descendants from the parent layout will not get focus anymore. You can try it out on your RecyclerView parent layout.
回答2:
I don't know if it's an issue, but the it looks like RecyclerView changed its behavior somewhere from support library 23.4.0 to 24.2.0.
Now instead of defaulting to descendantFocusability = beforeDescendants, it defaults to afterDescendants, which causes it to offer the focus to their children instead of taking it for itself.
When a child takes the focus, it ends up scrolling to make it visible.
I fixed it by adding android:descendantFocusability="beforeDescendants" to the RecyclerView, to recover the previous behavior, where it keeps the focus itself.
回答3:
I had a similar issue with RecyclerView scrolling, not specifically to NativeAdExpress...but there seems to be an issue with the Android Support library 24.0.0 related to this. The android:descendantFocusability="blocksDescendants" didn't work for me. But downgrading to Android Support library 23.4.0 made it start working again.
来源：https://stackoverflow.com/questions/37909408/nativeadsexpress-forces-recyclerview-to-scroll-to-have-the-nativead-fully-visibl