Android RecyclerView适配器中的弹出窗口
我是android的新手，我尝试在点击RecyclerView项时显示弹出窗口，但有点困惑，我看了一下，但无法理解这个上下文问题Android RecyclerView适配器中的弹出窗口,android,popup,android-recyclerview,adapter,Android,Popup,Android Recyclerview,Adapter,我是android的新手，我尝试在点击RecyclerView项时显示弹出窗口，但有点困惑，我看了一下，但无法理解这个上下文问题 public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> { private ArrayList<Mission> mDataset; public MyAdapter(ArrayList<Mission> myDataset) {
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private ArrayList<Mission> mDataset;
public MyAdapter(ArrayList<Mission> myDataset) {
mDataset = myDataset;
}
// Create new views (invoked by the layout manager)
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// create a new view
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.mission_card_item, parent, false);
// set the view's size, margins, paddings and layout parameters
MyViewHolder vh = new MyViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
holder.mTextView.setText(mDataset.get(position).getName());
holder.mPointView.setText(mDataset.get(position).getPoint());
holder.mRankView.setText(mDataset.get(position).getRank());
holder.btnAdd.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//Toast.makeText(v.getContext(),"Buton Clicked", Toast.LENGTH_SHORT).show();
}
});
}
@Override
public int getItemCount() {
return mDataset.size();
}
// 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 class MyViewHolder extends RecyclerView.ViewHolder {
public CardView mCardView;
public TextView mTextView;
public TextView mPointView;
public TextView mRankView;
public Button btnAdd;
public MyViewHolder(final View itemView) {
super(itemView);
mCardView = (CardView) itemView.findViewById(R.id.card_view);
mTextView = (TextView) itemView.findViewById(R.id.tv_text);
mRankView = (TextView) itemView.findViewById(R.id.tv_rank);
mPointView = (TextView) itemView.findViewById(R.id.tv_point);
btnAdd = (Button) itemView.findViewById(R.id.button_add);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
showPopup(itemView);
Toast.makeText(itemView.getContext(),"Element " + getAdapterPosition() + " clicked", Toast.LENGTH_SHORT).show();
Log.d("hello", "Element " + getAdapterPosition() + " clicked.");
}
});
}
}
public void showPopup(View view) {
View popupView = LayoutInflater.from(getActivity()).inflate(R.layout.popup_layout, null);
final PopupWindow popupWindow = new PopupWindow(popupView, WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.MATCH_PARENT);
Button btnDismiss = (Button) popupView.findViewById(R.id.ib_close);
btnDismiss.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
popupWindow.dismiss();
}
});
popupWindow.showAsDropDown(popupView, 0, 0);
}}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rl_custom_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="2dp"
android:background="#ab2fc4"
>
<ImageButton
android:id="@+id/ib_close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@mipmap/ic_launcher"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:background="@null"
/>
<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a sample popup window."
android:layout_centerInParent="true"
android:padding="25sp"
/>
</RelativeLayout>
getActivity（）无法解析并给出错误，如果有人能提供帮助，我将不胜感激。问题是您试图在适配器内调用方法getActivity（）。适配器将没有对活动或上下文的引用。活动将引用上下文，片段将引用父活动和上下文（getActivity（）和getContext（） 因此，在代码中进行这些更改首先从片段或活动将上下文传递给适配器的构造函数。然后使用该上下文来扩大布局。
private ArrayList<Mission> mDataset;
private Context mContext;
public MyAdapter(ArrayList<Mission> myDataset, Context context) {
mDataset = myDataset;
this.mContext = context;
}
public class PopupDialogFragment extends DialogFragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.popup_layout, container,
false);
return rootView;
}
}
public void showPopup() {
PopupDialogFragment dialogFragment = new PopupDialogFragment();
dialogFragment.show(((FragmentActivity)mContext).getSupportFragmentManager(), "OpenPopup");
}
问题是您试图在适配器内调用方法getActivity（）。适配器将没有对活动或上下文的引用。活动将引用上下文，片段将引用父活动和上下文（getActivity（）和getContext（） 因此，在代码中进行这些更改首先从片段或活动将上下文传递给适配器的构造函数。然后使用该上下文来扩大布局。
private ArrayList<Mission> mDataset;
private Context mContext;
public MyAdapter(ArrayList<Mission> myDataset, Context context) {
mDataset = myDataset;
this.mContext = context;
}
public class PopupDialogFragment extends DialogFragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.popup_layout, container,
false);
return rootView;
}
}
public void showPopup() {
PopupDialogFragment dialogFragment = new PopupDialogFragment();
dialogFragment.show(((FragmentActivity)mContext).getSupportFragmentManager(), "OpenPopup");
}
我添加了一个答案来回答您的问题，请让我知道这是否有帮助…我添加了其他内容。您可以检查对话片段的代码。我添加了一个答案来回答您的问题，请告诉我这是否有帮助…我添加了其他内容。您可以检查对话框片段的代码。我在我的主片段中也做了更改，我添加了如下上下文MyAdapter=newMyAdapter（myData，getContext（））；但当我运行应用程序并点击一些RecyclerView项目时，它会导致另一件事情崩溃。我不知道你为什么要把另一个布局放大成一个弹出窗口。。。请参考Android中的对话框片段。可能DialogFragment就是您要查找的java.lang.ClassCastException:android.support.v7.widget.AppCompatImageButton无法在com.example.yusuf.firebasedemoapp.MyAdapter.showPopup（MyAdapter）上强制转换为android.widget.Button。