android - RecyclerView 项目没有出现在正确的位置

Question

当我滚动 recyclerView 时，一些项目出现在它们不应该出现的位置。

在我应该只有“First”或只有“Second”的地方，我突然在一个 View 中同时拥有了“First Second”。

编辑:很可能它重用了一些 View ，但我该如何检查这是否正确？

我的代码是:

    @Override
public void onBindViewHolder(MyRecyclerAdapter.ViewHolder holder, int position) {
    DiaryDay item = items.get(position);
    holder.tvDay.setText(item.getDay());
    holder.tvMonth.setText(item.getMonth());
    showSplash(holder, item);

    if (holder.tvSunBathingMins!=null) {
        holder.tvSunBathingMins.setText(String.valueOf(item.getSunBathing()) + "  mins sunbathing. ");
    }

}

private void showSplash(ViewHolder holder, DiaryDay item) {
    if ( item.getSun_1() + item.getSun_2() + item.getSun_3() + item.getSun_4()  == 4   ) {
            holder.tvSplash2.setText( "All day! Amazing!");
    } else {
        if (item.getSun_1() != 0) {
            holder.tvSplash1.setText("First ");
        }
        if (item.getSun_2() != 0) {
            holder.tvSplash2.setText("Second ");
        }
        if (item.getSun_3() != 0) {
            holder.tvSplash3.setText("Third ");
        }
        if (item.getSun_4() != 0) {
            holder.tvSplash4.setText("Fourth ");
        }
    }

}




@Override
public MyRecyclerAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View v = LayoutInflater.from(parent.getContext()).inflate(itemLayout, parent, false);
    return new ViewHolder(v);
}

最后我的 ViewHolder 是:

   public static class ViewHolder extends RecyclerView.ViewHolder {
    public TextView tvDay;
    public TextView tvMonth;
    public TextView tvSplash1; public TextView tvSplash2; public TextView tvSplash3; public TextView tvSplash4;
    public TextView tvSunBathingMins;
    public TextView tvSumMins;

    public ViewHolder(View itemView) {
        super(itemView);
        tvDay = (TextView) itemView.findViewById(R.id.dayID);
        tvMonth = (TextView) itemView.findViewById(R.id.monthID);
        tvSplash1 = (TextView) itemView.findViewById(R.id.sun1);
        tvSplash2 = (TextView) itemView.findViewById(R.id.sun2);
        tvSplash3 = (TextView) itemView.findViewById(R.id.sun3);
        tvSplash4 = (TextView) itemView.findViewById(R.id.sun4);
        tvSunBathingMins = (TextView) itemView.findViewById(R.id.sunbathMinsID);
        tvSumMins = (TextView) itemView.findViewById(R.id.sumMinsID);

    }
}

Answer 1

问题在于您定义没有 else 子句的 if 语句的方式。当 View 持有者被回收时，会发生什么情况，诸如 tvSplash1、tvSplash2 等 View 仍然具有从离开屏幕的 View 分配的值。这就是为什么您需要按如下方式重置这些项目:

@Override
public void onBindViewHolder(MyRecyclerAdapter.ViewHolder holder, int position) {
    DiaryDay item = items.get(position);
    holder.tvDay.setText(item.getDay());
    holder.tvMonth.setText(item.getMonth());
    showSplash(holder, item);

    if (holder.tvSunBathingMins!=null) {
        holder.tvSunBathingMins.setText(String.valueOf(item.getSunBathing()) + "  mins sunbathing. ");
    } else {
        holder.tvSunBathingMins.setText("");
    }
}

private void showSplash(ViewHolder holder, DiaryDay item) {
    if ( item.getSun_1() + item.getSun_2() + item.getSun_3() + item.getSun_4()  == 4   ) {
            holder.tvSplash2.setText( "All day! Amazing!");
    } else {
        if (item.getSun_1() != 0) {
            holder.tvSplash1.setText("First ");
        } else {
            holder.tvSplash1.setText("");
        }

        if (item.getSun_2() != 0) {
            holder.tvSplash2.setText("Second ");
        } else {
            holder.tvSplash2.setText("");
        }
        if (item.getSun_3() != 0) {
            holder.tvSplash3.setText("Third ");
        } else {
            holder.tvSplash3.setText("");
        }
        if (item.getSun_4() != 0) {
            holder.tvSplash4.setText("Fourth ");
        } else {
            holder.tvSplash4.setText("");
        }
    }
}