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
我们可以使用Java弱引用来实现这一点。 从语义上讲,视图持有者应该响应click事件或将其委托给正确的响应器。
我们的目标:
Viewholder应该对响应事件的类一无所知,除非它实现了某个接口。 点击处理程序应该得到被点击的视图在RecyclerView中的位置。 我们应该能够辨别视图持有人中单击了哪个视图。 保持所有组件之间的松散耦合,不要造成任何保留周期。
步骤:
Create an interface to handle click responses. Implement this interface in the Activity that will handle the click. Add a member variable in the RecyclerView Adapter to hold the Weak Reference and a constructor that sets it. Do the same in the RecyclerView ViewHolder and add a member variable to keep track of position. Set your on click listeners on any view you'd like in the ViewHolder, then callback to the responder to handle them. Change your onBindViewHolder method to set the position when binding. Pass the responder down to the ViewHolder. In the responder, you can now use getId() on the view to figure out which view was clicked.
这里是一个要点,这样你就可以看到它们是如何组合在一起的: RecyclerView点击处理
其他回答
有更简单的方法。只需要在根视图上应用onBindViewHolder中的click。
考虑这是你对适配器的看法,
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/linearlayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/textview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="1dp"
android:textSize="15sp" />
</LinearLayout>
然后在适配器中执行以下操作
//get the layout and make view holder
@Override
public RVAdapter.ViewHolder1 onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.adapter_layout, null);
ViewHolder1 viewHolder = new ViewHolder1(view);
return viewHolder;
}
@Override
public void onBindViewHolder(RVAdapter.ViewHolder1 holder, int position) {
//apply on click on your root view
holder.linearlayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//Do on click stuff
}
});
}
//make references to views in layout including root view
public class ViewHolder1 extends RecyclerView.ViewHolder {
protected LinearLayout linearlayout = null
protected TextView textview = null;
public CareerLinksViewHolder(View itemView) {
super(itemView);
this.linearlayout = (LinearLayout) itemView.findViewById(R.id.linearlayout);
this.tvCompName = (TextView) itemView.findViewById(R.id.textview);
}
}
我知道有很多答案,但我想我也可以提供我的实现。(完整的细节可以在我回答的另一个问题中找到)。
所以,要添加一个点击监听器,你的内部ViewHolder类需要实现View.OnClickListener。这是因为你将设置一个OnClickListener到ViewHolder的构造函数的itemView参数。让我来告诉你我的意思:
public class ExampleClickViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
TextView text1, text2;
ExampleClickViewHolder(View itemView) {
super(itemView);
// we do this because we want to check when an item has been clicked:
itemView.setOnClickListener(this);
// now, like before, we assign our View variables
title = (TextView) itemView.findViewById(R.id.text1);
subtitle = (TextView) itemView.findViewById(R.id.text2);
}
@Override
public void onClick(View v) {
// The user may not set a click listener for list items, in which case our listener
// will be null, so we need to check for this
if (mOnEntryClickListener != null) {
mOnEntryClickListener.onEntryClick(v, getLayoutPosition());
}
}
}
唯一需要添加的其他东西是适配器的自定义接口和setter方法:
private OnEntryClickListener mOnEntryClickListener;
public interface OnEntryClickListener {
void onEntryClick(View view, int position);
}
public void setOnEntryClickListener(OnEntryClickListener onEntryClickListener) {
mOnEntryClickListener = onEntryClickListener;
}
这样,新的支持单击的适配器就完成了。
现在,让我们用它…
ExampleClickAdapter clickAdapter = new ExampleClickAdapter(yourObjects);
clickAdapter.setOnEntryClickListener(new ExampleClickAdapter.OnEntryClickListener() {
@Override
public void onEntryClick(View view, int position) {
// stuff that will happen when a list item is clicked
}
});
这基本上就是设置普通适配器的方法,除了使用您创建的setter方法来控制当用户单击特定列表项时要做什么。
你也可以看看我在GitHub上做的一组关于Gist的例子:
https://gist.github.com/FarbodSalamat-Zadeh/7646564f48ee708c1582c013e1de4f07
这对我来说很管用。将OnClickListener附加到onBindView。我真的不知道这是否会影响性能,但它似乎用很少的代码就能很好地工作。
public void onBindViewHolder(ViewHolder holder, final int position) {
holder.view.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast.makeText(context, "Recycle Click" + position, Toast.LENGTH_SHORT).show();
}
});
}
您可以将clickListener传递给适配器。
在活动中:
private View.OnClickListener mItemClick = new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = null;
int position = list.getChildPosition(v);
switch (position) {
case 0:
intent = new Intent(MainActivity.this, LeakCanaryActivity.class);
break;
case 1:
intent = new Intent(MainActivity.this, ButterKnifeFragmentActivity.class);
break;
}
if (intent != null) {
MainActivity.this.startActivity(intent);
}
}
};
然后将它传递给适配器:
MainAdapter mainAdapter = new MainAdapter(this, mItemClick);
在适配器的onCreateViewHolder中:
@Override
public MainAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int position) {
View itemView = activity.getLayoutInflater().inflate(R.layout.main_adapter_item, viewGroup, false);
ViewHolder holder = new ViewHolder(itemView);
itemView.setOnClickListener(mItemClick);
return holder;
}
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);
}
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