如何在onBindViewHolder（）中的notifyItemChange（）之后为recyclerView元素中的子视图设置动画

Question

我想给a textView内部的动画，recyclerView以便在调用时向上过渡notifyItemChanged(position)。这是我的onBindViewholder()，当适配器发生更改时，它会自动被调用：

@Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
    if (unfoldedIndexes.contains(position)) { // if already unfolded
        bindUnfoldedState(holder, holder.getLayoutPosition());
    }else{ // show the folded state}
}

public void bindUnfoldedState(ViewHolder holder, int position){


    if(lc.isBtnEnabled()){
            holder.Price.setText("text");
            holder.Price.animate().alpha(1.0f).setDuration(500);
            holder.Price.animate().translationY(-38).setDuration(500);
            holder.checkText.animate().translationY(38).setDuration(500);
        }else {
            holder.Price.animate().alpha(0.0f).setDuration(500);
            holder.Price.animate().translationY(0).setDuration(500);
            holder.checkText.animate().translationY(0).setDuration(500);
        }

}

我notifyItemChanged()被这样称呼fragment onClick：

 ok.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View view) {
            // some changes to the data
            adapter.getLcns().get(Position).setBtnEnabled(true);
            adapter.notifyItemChanged(Position);
            }
}

isBtnEnabled()如果etBtnEnabled(true)调用s 为true 。

问题是动画没有发生。使用日志，我可以确认onBindViewHolder()正在调用该动画，并且应该出现动画但没有发生。

listView在转换为a之前，我使用了recyclerView正常模式，并且动画正在制作中getView()

Answer 1

用于Adapter.notifyItemChanged(position, payload)将更新部署到已经可见的 ViewHolder：

单击时：

ok.setOnClickListener(new View.OnClickListener(){
    @Override
    public void onClick(View view) {
        // some changes to the data
        adapter.getLcns().get(Position).setBtnEnabled(true);
        adapter.notifyItemChanged(Position, true);   // "true" is the payload
    }
}

适配器：

@Override
public void onBindViewHolder(@NonNull ViewHolder holder, int position, List<Object> payloads) {
    if(payloads != null && !payloads.isEmpty()){  // update payloads, partial rebind
        Object lastPayload = payloads.get(payloads.size -1)); // in this case only last payload is meaningful
        if(lastPayload instanceof Boolean)
            bindUnfoldedState(holder, lastPayload);
    }else
        onBindViewHolder(holder, position);   // regular binding of item
}

public void bindUnfoldedState(ViewHolder holder, boolean unfold){
     if(unfold){ ... } 
     else { ... }
}

// you should also consider adding this override to prevent animation leaking when viewholder
// is recycled and reused for another position:
@Override
public void onViewRecycled(ViewHolder holder){
    holder.Price.animate().cancel();
    holder.checkText.animate().cancel();
}