当一个Recyclerview项目被展开时,折叠所有其他Recyclerview项目。

5

我有一个良好设置的可扩展 Recyclerview。当点击任何项目时,它会展开以显示更多细节。但我想在这里做出一些改变。当单击一个项目以展开时,所有其他项目都应该折叠。这是我的适配器代码:

public class DataAdapter extends RecyclerView.Adapter<DataAdapter.ViewHolder> {
    private ArrayList<ListItem> android_versions;
    private List<ListItem> listItems;
    private LayoutInflater layoutInflater;
    private Animation animationUp, animationDown;
    private Context context;
    private final int COUNTDOWN_RUNNING_TIME = 500;
    int i =0;

    public DataAdapter(Context context, java.util.List<ListItem> android_versions,
                       Animation animationUp, Animation animationDown) {
        this.context = context;
        this.listItems = android_versions;
        this.animationDown = animationDown;
        this.animationUp = animationUp;
    }

    @Override
    public DataAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row_layout, viewGroup, false);
        return new ViewHolder(view);
    }

    public String getRandomColor(int a){
        String colors[] = {"#ef5350","#f44336","#ef5350"};
        return colors[a];
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, int i) {
        ListItem listItem = listItems.get(i);
        if (i%2==2)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(0)));
        else if (i%2==1)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(1)));
        else if (i%2==0)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(2)));

        holder.tv_android.setText(listItem.getSubName());
        holder.contentLayout.setText(listItem.getContent());
        holder.expandit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                if (holder.contentLayout.isShown()) {
                    holder.contentLayout.startAnimation(animationUp);
                    CountDownTimer countDownTimerStatic = new CountDownTimer(COUNTDOWN_RUNNING_TIME, 16) {
                        @Override
                        public void onTick(long millisUntilFinished) {
                        }

                        @Override
                        public void onFinish() {
                            holder.contentLayout.setVisibility(View.GONE);
                        }
                    };
                    countDownTimerStatic.start();
                } else {
                    holder.contentLayout.setVisibility(View.VISIBLE);
                    holder.contentLayout.startAnimation(animationDown);
                }
            }
        });
    }
    @Override
    public int getItemCount() {
        return listItems.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder{
        TextView tv_android;
        private TextView contentLayout;
        RelativeLayout expandit;
        public ViewHolder(View view) {
            super(view);
            tv_android = (TextView)view.findViewById(R.id.tv_android);
            contentLayout = (TextView) view.findViewById(R.id.content);
            expandit = (RelativeLayout)view.findViewById(R.id.expandit);
        }
    }
}

我认为无法通过位置更改viewHolder的内容。那么我如何通过位置隐藏所有其他项目的内容?我认为不需要其他代码,因此我没有包含它。
编辑:在Ashish建议之后的代码:
  private void changeStateOfItemsInLayout(ListItem listItem) {
        for (int i = 0; i < listItems.size(); i++) {
            if (listItems.get(i) == listItem)
                listItem.setShouldBeExpanded(true);
            else
                listItem.setShouldBeExpanded(false);
        }
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, int i) {
        ListItem listItem = listItems.get(i);
        if (i%2==2)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(0)));
        else if (i%2==1)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(1)));
        else if (i%2==0)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(2)));

        holder.tv_android.setText(listItem.getSubName());
        holder.contentLayout.setText(listItem.getContent());
        if(listItem.getShouldBeExpanded()){
            holder.contentLayout.setVisibility(View.VISIBLE);
            holder.contentLayout.startAnimation(animationDown);
        }else{
            holder.contentLayout.startAnimation(animationUp);
            CountDownTimer countDownTimerStatic = new CountDownTimer(COUNTDOWN_RUNNING_TIME, 16) {
                @Override
                public void onTick(long millisUntilFinished) {
                }

                @Override
                public void onFinish() {
                    holder.contentLayout.setVisibility(View.GONE);
                }
            };
            countDownTimerStatic.start();
        }

        holder.expandit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (holder.contentLayout.isShown()) {
                    holder.contentLayout.startAnimation(animationUp);
                    CountDownTimer countDownTimerStatic = new CountDownTimer(COUNTDOWN_RUNNING_TIME, 16) {
                        @Override
                        public void onTick(long millisUntilFinished) {
                        }

                        @Override
                        public void onFinish() {
                            holder.contentLayout.setVisibility(View.GONE);
                        }
                    };
                    countDownTimerStatic.start();
                } else {
                    holder.contentLayout.setVisibility(View.VISIBLE);
                    holder.contentLayout.startAnimation(animationDown);
                }
                listItems.get(holder.getLayoutPosition()).setShouldBeExpanded(true);
                changeStateOfItemsInLayout(listItems.get(holder.getLayoutPosition()));
                notifyDataSetChanged();
            }
        });
    }

虽然在onClick中,我仍然有展开/折叠布局的代码,但即使我删除它,它也不起作用。

如果需要,这是我的模态框类:

public class ListItem {

    private String subName;
    private String content;
    private String param;
    private Boolean shouldBeExpanded=false;

    public Boolean getShouldBeExpanded() {
        return shouldBeExpanded;
    }

    public void setShouldBeExpanded(Boolean shouldBeExpanded) {
        this.shouldBeExpanded = shouldBeExpanded;
    }

    public ListItem(String subName, String content) {
        this.subName = subName;
        this.content = content;
        this.param = "Nothing";
    }

    public String getParam() {
        return param;
    }

    public ListItem(String subName, String content, String param) {

        this.subName = subName;
        this.content = content;
        this.param = param;
    }

    public String getSubName() {
        return subName;
    }

    public String getContent() {
        return content;
    }
}

编辑:根据要求,以下是animationUp文件和animationDown文件的代码:

animationUp.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:fillAfter="true" >

    <scale
        android:duration="200"
        android:fromXScale="1.0"
        android:fromYScale="1.0"
        android:interpolator="@android:anim/linear_interpolator"
        android:toXScale="1.0"
        android:toYScale="0.0" />

</set>

animationDown.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:fillAfter="true">

    <scale
        android:duration="200"
        android:fromXScale="1.0"
        android:fromYScale="0.0"
        android:interpolator="@android:anim/accelerate_interpolator"
        android:toXScale="1.0"
        android:toYScale="1.0" />

</set>
3个回答

5
感谢Ashish,通过简单的逻辑我解决了这个问题。以下是我重新定义了的changeStateOfItemsInLayout函数代码:
private void changeStateOfItemsInLayout(ListItem listItem, int p) {
        for (int x = 0; x < listItems.size(); x++) {
            if (x == p) {
                listItem.setShouldBeExpanded(true);
                //Since this is the tapped item, we will skip
                //the rest of loop for this item and set it expanded
                continue;
            }
            listItems.get(x).setShouldBeExpanded(false);
        }
    }

这个函数负责收起所有其他的项目。它会检查哪个选项被点击并展开它(如果已经展开,则不会从OnBindViewHolder函数中调用此函数),并且折叠所有其他选项。
这是我的完整适配器代码:
public class DataAdapter extends RecyclerView.Adapter<DataAdapter.ViewHolder> {
    private ArrayList<ListItem> android_versions;
    private List<ListItem> listItems;
    private LayoutInflater layoutInflater;
    private Animation animationUp, animationDown;
    private Context context;
    private final int COUNTDOWN_RUNNING_TIME = 300;

    public DataAdapter(Context context, java.util.List<ListItem> android_versions,
                       Animation animationUp, Animation animationDown) {
        this.context = context;
        this.listItems = android_versions;
        this.animationDown = animationDown;
        this.animationUp = animationUp;
    }

    @Override
    public DataAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row_layout, viewGroup, false);
        return new ViewHolder(view);
    }

    public String getRandomColor(int a){
        String colors[] = {"#ef5350","#f44336","#ef5350"};
        return colors[a];
    }

    private void changeStateOfItemsInLayout(ListItem listItem, int p) {
        for (int x = 0; x < listItems.size(); x++) {
            if (x == p) {
                listItem.setShouldBeExpanded(true);
                //Since this is the tapped item, we will skip
                //the rest of loop for this item and set it expanded
                continue;
            }
            listItems.get(x).setShouldBeExpanded(false);
        }
    }


    @Override
    public void onBindViewHolder(final ViewHolder holder, int i) {
        ListItem listItem = listItems.get(i);
        if (i%2==2)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(0)));
        else if (i%2==1)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(1)));
        else if (i%2==0)
            holder.itemView.setBackgroundColor(Color.parseColor(getRandomColor(2)));

        holder.tv_android.setText(listItem.getSubName());
        holder.contentLayout.setText(listItem.getContent());
        if(listItem.getShouldBeExpanded()){
            holder.contentLayout.setVisibility(View.VISIBLE);
            holder.contentLayout.startAnimation(animationDown);
        }else{
            holder.contentLayout.startAnimation(animationUp);
            CountDownTimer countDownTimerStatic = new CountDownTimer(COUNTDOWN_RUNNING_TIME, 16) {
                @Override
                public void onTick(long millisUntilFinished) {}
                @Override
                public void onFinish() {
                    holder.contentLayout.setVisibility(View.GONE);
                }
            };
            countDownTimerStatic.start();
        }

        holder.expandit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (holder.contentLayout.isShown()) {
                    listItems.get(holder.getLayoutPosition()).setShouldBeExpanded(false);
                } else {
                    listItems.get(holder.getLayoutPosition()).setShouldBeExpanded(true);
                    changeStateOfItemsInLayout(listItems.get(holder.getLayoutPosition()),holder.getLayoutPosition());
                }
                notifyDataSetChanged();
            }
        });
    }
    @Override
    public int getItemCount() {
        return listItems.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder{
        TextView tv_android;
        private TextView contentLayout;
        RelativeLayout expandit;
        public ViewHolder(View view) {
            super(view);
            tv_android = (TextView)view.findViewById(R.id.tv_android);
            contentLayout = (TextView) view.findViewById(R.id.content);
            expandit = (RelativeLayout)view.findViewById(R.id.expandit);
        }
    }
}

你能提供animationUp和animationDown的代码吗? - Fathima km
@Fathimakm,我已经编辑了帖子并添加了你的代码,请检查! - Paras Sidhu

2

在您的ListItem类中(我假设这是模型类),添加一个新的布尔变量shouldBeExpanded,并将其默认值设置为false,并编写其getter和setter。现在,在您的适配器中,在onBindViewHolder中编写以下代码:

if(listItem.shouldBeExpanded()){
//write your code to expand it
}else{
//write the code to collapse
}

现在在代码部分,对于一些展开布局的onClick事件,在此将该变量设置为true,并调用一个函数,将listItem中的所有其他项设置为false,以便shouldBeExpanded。通过调用以下函数changeStateOfItemsInLayout(listItem)来实现。现在调用notifyDataSetChanged()。
private void changeStateOfItemsInLayout(ListItem listItem){
for(int i=0;i<listItems.size();i++){
if(listItems.get(i)==listItem)
listItem.get(i).setShouldBeExpanded(true);
}else{
listItem.get(i).setShouldBeExpanded(false);
}
}

这应该能解决你的问题。

对我没用。当我点击一个项目时,它会短暂地展开,然后立即折叠,除了最后一个项目。 - Paras Sidhu
出现了问题。我一直在使用listItem作为final,但是删除了final关键字。问题仍然存在。 - Paras Sidhu
我还没有看到它。 - Ashish Kumar
在onBindViewHolder函数的上方 - Paras Sidhu
你能否调试一下,在你调用notifyDataSetChanges()之后,查看shouldBeExpanded的值是否为正确列表项为true,其他列表项为false? - Ashish Kumar
我重新定义了逻辑,现在它可以工作了 :) 我已经将整个代码发布为答案。 - Paras Sidhu

0
我花了几个小时来调整ExpandableRecyclerAdapter代码。但实际上它非常简单。在你的活动中,你有监听器来监听展开/折叠事件,并且当前父列表项位置正在被展开/折叠。跟踪currentExpandedPosition并调用适配器collapseParent来折叠先前展开的项目。只需5行代码就可以实现完美的手风琴效果。
private currentExpandedPosition = -1;

        mAdapter.setExpandCollapseListener(new ExpandableRecyclerAdapter.ExpandCollapseListener() {
        @Override
        public void onListItemExpanded(int position) {

            if (currentExpandedPosition >= 0){
                mAdapter.collapseParent(currentExpandedPosition);
            }
            currentExpandedPosition = position;
        }

        @Override
        public void onListItemCollapsed(int position) {

           currentExpandedPosition = -1;
        }
    });

网页内容由stack overflow 提供, 点击上面的
可以查看英文原文,
原文链接