有人使用RecyclerView找到了一种方法来设置一个onClickListener的项目在RecyclerView? 我想设置一个监听器为每个项目的布局,但这似乎有点太麻烦了 我确信有一种方法让RecyclerView监听onClick事件,但我不能完全弄清楚。
当前回答
From most of the answers above, they seem to be setting their onclicklisteners to individual items. However, the solution am about to offer is very simple but yet not intuitive to many. Many are forgetting that the other components are always in a parent component which is used to display items in the List or Recycler views. This solution is just about setting a single onclick listener to this parent view and the turn is played. The solution also includes a way to pass the position of the item being clicked on from the list or recycler view. Here, our main rootview is a CardView from the android support library. Here is sample code
public class ListAdapter extends RecyclerView.Adapter<ListAdapter.ViewHolder> {
public static final String LOG_TAG = ListAdapter.class.getSimpleName();
private Cursor mDataset;
private Context mContext;
private ViewHolder mViewHolder;
// Provide a suitable constructor (depends on the kind of dataset)
public ListAdapter(Context context, Cursor Dataset) {
mDataset = Dataset;
mContext = context;
}
// Create new views (invoked by the layout manager)
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// create a new view
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.list_business_view, parent, false);
mViewHolder = new ViewHolder(v);
return mViewHolder;
}
public void setData(Cursor newdata) {
this.mDataset = newdata;
}
// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
//Bind data to other items here. To save time, i have ommited that.
//here is where we attach a click listerner for an item in the recycler list rather than for each element of a given item.
holder.card.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(mContext, " Just cliked item at position " + itemPosition, Toast.LENGTH_LONG).show();
}
});
}
}
// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
if (null != mDataset) {
return mDataset.getCount();
}
return 0;
}
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public static class ViewHolder extends RecyclerView.ViewHolder{
// each data item is just a string in this case
public final TextView mBusinesssName; // View for the business name
public final TextView mBusinessCategory; //View for the category name
public final ImageView businessImage; // View for the business category image Image
public final TextView mBusinessDistance; // View for the distance
public final CardView card;
public ViewHolder(View view) {
super(view);
mBusinesssName = (TextView) view.findViewById(R.id.list_item_name_textview);
mBusinessCategory = (TextView) view.findViewById(R.id.list_item_category_textview);
mBusinessDistance = (TextView) view.findViewById(R.id.list_item_dist_textview);
businessImage = (ImageView) view.findViewById(R.id.list_item_icon);
card = (CardView) view.findViewById(R.id.card_view);
}
}
}
其他回答
通常你在CardView中有多个元素,所以你需要一个布局视图来包装和组织它们。你可以添加一个OnClickListener到那个布局视图。1. 添加一个id到你的布局。在这个例子中是线性布局
<android.support.v7.widget.CardView
.....>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/card_view_linearLayout">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="name"
android:id="@+id/card_view_name" />
...
</LinearLayout>
</android.support.v7.widget.CardView>
2美元。在你的内部ViewHolder类中获取布局视图。
public static class ViewHolder extends RecyclerView.ViewHolder{
private TextView nameView;
...
private LinearLayout linearLayout;
public ViewHolder(View itemView) {
super(itemView);
nameView = (TextView)itemView.findViewById(R.id.card_view_name);
...
linearLayout = (LinearLayout)itemView.findViewById(R.id.card_view_linearLayout);
}
}
3美元。将监听器添加到onBindViewHolder中的布局中,并使用回调将数据发送到活动或片段(未测试)。
@Override
public void onBindViewHolder(TrackAdapter.ViewHolder holder, final int position) {
String str = mStringList.get(position);
holder.nameView.setText(str);
...
holder.linearLayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
callback.itemCallback(mStringList.get(position));
}
});
}
如何使用回调是另一个故事
查看类似的问题@CommonsWare的评论链接到this,它在viewHolder中实现了OnClickListener接口。
下面是ViewHolder的一个简单例子:
/** Declare global with in adapter class. */
TextView textView;
public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
textView = (TextView) view.findViewById(android.R.id.text1);
}
@Override
public void onClick(View view) {
Toast.makeText(view.getContext(), "position = " + getLayoutPosition(), Toast.LENGTH_SHORT).show();
/** Go through each item if you have few items within RecyclerView. */
if (getLayoutPosition() == 0) {
// Do whatever you want here
} else if(getLayoutPosition() == 1) {
// Do whatever you want here
} else if(getLayoutPosition() == 2) {
// Do whatever you want here
}
/** Or you can use For loop if you have long list of items. */
for (int i = 0; i < exampleList.size(); i++) {
// Do whatever you want here
}
}
}
在你的RecyclerView中创建ViewHolder。适配器看起来像这样:
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext())
View view = inflater.inflate(android.R.layout.simple_list_item_1, parent, false);
return new ViewHolder(view);
}
到目前为止,所有的答案都是很好的解决方案,但是如果你不想处理太多的实现细节,只是想让它类似于ListView的工作方式,我建议使用twway - view,如下所示:
https://github.com/lucasr/twoway-view
请注意,这个实现还支持长按项目,以及支持按下状态(这是这个问题的其他解决方案所缺乏的重要内容)。
如果您不想使用整个库,请查看ClickItemTouchListener类,如果需要,可以将其作为独立的类使用。我发现它目前唯一的问题是长按+滚动,它似乎有不正确的行为。
别白费力气了!这个特定用例的代码包含在Android Studio附带的Master/Detail Flow启动器项目中。
从Android Studio选择:
文件>新建>新建项目.... 在Phone and Tablet选项卡中选择如下所示的Master/Detail Flow。
用Kotlin或Java创建项目。 利润。
我不会在这里包括谷歌的ootb演示项目的代码,但我会概述谷歌提供的示例中的主要设计方法:
the item OnClickListener is created ONLY ONCE, and is assigned to a field in your RecyclerView.Adapter implementation. in the onBindViewHolder() you should set the same, pre-created onClickListener object on your ViewHolder instance with holder.itemView.setOnClickListener(mOnClickListener) (AVOID creating a new instance on every method call!); if you need to capture clicks on some specific elements inside the ViewHolder then extend ViewHolder and expose the elements you need as fields so that you can attach whatever listeners you need in onBindViewHolder() — and once again, do NOT re-create the listeners on every method call — initialise them as instance fields and attach them as needed. you can use .setTag() in order to pass state to your viewHolder, e.g. holder.itemView.setTag(mValues.get(position)); as used in the demo.
这就是重用View的方法。OnClickListener:
public class TestAdapter extends RecyclerView.Adapter<TestAdapter.MyviewHolder>
implements View.OnClickListener
在ViewHoder中获取项目布局的父视图:
public class MyviewHolder extends RecyclerView.ViewHolder {
LinearLayout linearLayout;
public MyviewHolder(View itemView) {
super(itemView);
linearLayout = itemView.findViewById(R.id.linear_layout_item);
}
}
在onBindViewHolder中设置标签为位置:
@Override
public void onBindViewHolder(MyviewHolder holder, int position) {
holder.linearLayout.setTag(position);
holder.linearLayout.setOnClickListener(this);
}
在你的onClick实现中:
@Override
public void onClick(View v) {
int position = (int) v.getTag();
switch (v.getId()) {
case R.id.linear_layout_item:
// do some thing with position
break;
}
}
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