【发布时间】：2017-06-14 21:31:15
【问题描述】：
我不明白滚动浏览我的 RecyclerView 时刹车的原因是什么。滚动由mRecyclerView.smoothScrollToPosition(position); 调用
当您滚动浏览抽搐列表时（渲染时间范围> 16ms）
AlphaAdapter.java
public class AlphaAdapter extends RecyclerView.Adapter<AlphaAdapter.ViewHolder> {
private static final String TAG = "AlphaAdapter";
private Context mContext;
private List<PrimaryWeapon> mGunList;
private boolean isAnimate;
private final int VIEW_TYPE_NULL = 0;
private final int VIEW_TYPE_ITEM = 1;
public AlphaAdapter(Context mContext, List<PrimaryWeapon> mGunList) {
this.mContext = mContext;
this.mGunList = mGunList;
}
public AlphaAdapter(Context mContext, List<PrimaryWeapon> mGunList, boolean a) {
this.mContext = mContext;
this.mGunList = mGunList;
this.isAnimate = a;
}
@Override
public int getItemViewType(int position) {
try {
if (mGunList.get(position).getNameWeapon().equals(""))
return VIEW_TYPE_NULL;
else return VIEW_TYPE_ITEM;
} catch (Exception e) {
e.printStackTrace();
Log.e("AlphaAdapter", String.valueOf(position));
return VIEW_TYPE_NULL;
}
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = null;
if (viewType == VIEW_TYPE_ITEM)
view = LayoutInflater.from(mContext).inflate(R.layout.item_game, parent, false);
else
view = LayoutInflater.from(mContext).inflate(R.layout.item_null, parent, false);
return new ViewHolder(view);
}
@Override
public void onViewDetachedFromWindow(ViewHolder holder) {
super.onViewDetachedFromWindow(holder);
holder.itemView.clearAnimation();
}
@Override
public boolean onFailedToRecycleView(ViewHolder holder) {
return true;
}
@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
try {
long startTime = System.currentTimeMillis();
if (!getWeapon(position).getNameWeapon().equals("")) {
if (isAnimate) {
if (mLastAnimPosition < position) {
mLastAnimPosition = position;
Animation a = AnimationUtils.loadAnimation(mContext, R.anim.item_game_anim);
holder.itemView.startAnimation(a);
a.setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
}
@Override
public void onAnimationEnd(Animation animation) {
}
@Override
public void onAnimationRepeat(Animation animation) {
}
});
}
}
Picasso.with(mContext)
.load("file:///android_asset/" + getWeapon(position).getImagePath())
.placeholder(R.drawable.loading)
.error(R.drawable.load_fail)
.into(holder.image);
holder.main.setText(getWeapon(position).getNameWeapon());
holder.desc.setText(getWeapon(position).getNameSkin());
}
Log.i(TAG, String.valueOf(System.currentTimeMillis() - startTime) + "ms onBind (" + String.valueOf(position) + ");");
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public long getItemId(int position) {
return position;
}
private PrimaryWeapon getWeapon(int position) {
return mGunList.get(position);
}
@Override
public int getItemCount() {
return mGunList.size();
}
class ViewHolder extends RecyclerView.ViewHolder {
TextView main, desc;
ImageView image;
ViewHolder(View itemView) {
super(itemView);
main = (TextView) itemView.findViewById(R.id.item_textMain);
desc = (TextView) itemView.findViewById(R.id.item_textDescription);
image = (ImageView) itemView.findViewById(R.id.item_image);
}
}
}
参与适配器的Layout元素由LinearLayout、ImageView、2个TextView组成。
一开始以为是下载图片的问题，尝试加载到AsyncTask中，通过Picasso上传位图，没有，但毕竟从他们的标记中删除，列表仍然会滞后。
滚动后dump RAM，显示原来有71个内存实例ViewHolder，添加后
@Override
public boolean onFailedToRecycleView(ViewHolder holder) {
return true;
}
此值减少到 15-16，although the rate for RecyclerView - 5 复制，它应该覆盖它们，但在滚动时不会创建新的。
item_null.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="74dp"
android:layout_height="80dp">
</LinearLayout>
item_game.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_gravity="center"
android:padding="2dp"
android:id="@+id/layout"
android:layout_height="80dp"
android:fitsSystemWindows="true"
android:layout_width="74dp">
<ImageView
android:id="@+id/item_image"
android:layout_width="match_parent"
android:layout_height="56dp"
/>
<TextView
android:layout_gravity="top"
android:layout_width="match_parent"
android:singleLine="true"
android:id="@+id/item_textMain"
android:paddingLeft="4dp"
android:paddingRight="4dp"
android:paddingTop="1dp"
android:gravity="left"
android:textColor="#FFF"
android:maxLines="1"
android:textSize="8sp"
android:layout_height="10dp" />
<TextView
android:layout_gravity="bottom"
android:layout_width="match_parent"
android:id="@+id/item_textDescription"
android:paddingLeft="4dp"
android:paddingRight="4dp"
android:gravity="left"
android:textColor="#FFF"
android:singleLine="true"
android:maxLines="1"
android:maxLength="40"
android:textSize="6sp"
android:layout_height="12dp" />
</LinearLayout>
【问题讨论】：
-
你能发布布局吗？
R.layout.item_game和R.layout.item_null -
@11 添加了布局
-
您是否尝试过只加载一次动画？就像在适配器的构造函数中一样？
-
我尝试在 RV 中的所有项目上设置动画，前提是 boolean isAnimate == true
-
在这个问题中动画被禁用
标签： java android android-studio android-recyclerview