找不到接受参数类型 'androidx.lifecycle.LiveData< 的 ~ItemBinding~ 的 setter
Cannot find a setter for ~ItemBinding~ that accepts parameter type 'androidx.lifecycle.LiveData<
Cannot find a setter for
<the_derek.dogstuff.databinding.DogItemBinding app:product> that
accepts parameter type
'androidx.lifecycle.LiveData<the_derek.dogstuff.db.entity.DogEntity>'
If a binding adapter provides the setter, check that the adapter is
annotated correctly and that the parameter type matches.
两天多来,我一直在逐行浏览我的应用程序。我使用 Google 提供的“BasicSample”Android Room 应用程序来模拟我自己的应用程序,但是当我将其包含在我的 dog_fragment.xml
中时出现此错误
<include
layout="@layout/dog_item"
app:product="@{dogViewModel.dog}" />
“dog_item”布局(dog_item.xml)用于显示狗的列表,当您单击它时,它将带您进入狗的详细信息屏幕(dog_fragment.xml).没有它,一切都很好,但它缺少在详细信息屏幕中播放的“狗”图块,并且只会显示 chew_toys.
的列表
dog_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<import type="android.view.View" />
<variable
name="isLoading"
type="boolean" />
<variable
name="dog"
type="the_derek.dogstuff.viewmodel.DogViewModel" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/cardview_light_background"
android:orientation="vertical">
<include
layout="@layout/dog_item"
app:product="@{dogViewModel.dog}" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/tv_loading_chew_toys"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="@string/loading_chew_toys"
app:visibleGone="@{isLoading}" />
<FrameLayout
android:id="@+id/chew_toys_list_wrapper"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/chew_toy_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="@string/cd_chew_toys_list"
app:layoutManager="LinearLayoutManager"
app:visibleGone="@{!isLoading}" />
</FrameLayout>
</FrameLayout>
</LinearLayout>
</layout>
DogFragment.java
public class DogFragment extends Fragment {
private static final String TAG = "\t\tDogFragment";
private static final String KEY_DOG_ID = "dog_id";
private final ChewToyClickCallback mChewToyClickCallback =
chewToy -> {
// no-op
};
private DogFragmentBinding mBinding;
private ChewToyAdapter mChewToyAdapter;
public static DogFragment forDog(int dogId) {
DogFragment fragment = new DogFragment();
Bundle args = new Bundle();
args.putInt(KEY_DOG_ID, dogId);
fragment.setArguments(args);
return fragment;
}
@Nullable
@Override
public View onCreateView(
@NonNull LayoutInflater inflater,
@Nullable ViewGroup container,
@Nullable Bundle savedInstanceState) {
mBinding = DataBindingUtil.inflate(inflater, R.layout.dog_fragment, container, false);
mChewToyAdapter = new ChewToyAdapter(mChewToyClickCallback);
mBinding.chewToyList.setAdapter(mChewToyAdapter);
return mBinding.getRoot();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
DogViewModel.Factory factory =
new DogViewModel.Factory(
requireActivity().getApplication(), requireArguments().getInt(KEY_DOG_ID));
final DogViewModel model =
new ViewModelProvider(this, factory).get(DogViewModel.class);
mBinding.setLifecycleOwner(getViewLifecycleOwner());
mBinding.setDogViewModel(model);
subscribeToModel(model);
}
private void subscribeToModel(final DogViewModel model) {
model
.getChewToys()
.observe(
getViewLifecycleOwner(),
chewToyEntities -> {
if (chewToyEntities != null) {
mBinding.setIsLoading(false);
mChewToyAdapter.submitList(chewToyEntities);
} else {
mBinding.setIsLoading(true);
}
});
}
@Override
public void onDestroyView() {
mBinding = null;
mChewToyAdapter = null;
super.onDestroyView();
}
}
DogViewModel.java
public class DogViewModel extends AndroidViewModel {
private static final String TAG = "\t\tDogViewModel";
private final LiveData<DogEntity> mObservableDog;
private final LiveData<List<ChewToyEntity>> mObservableChewToys;
public DogViewModel(
@NonNull Application application, DataRepository repository, final int dogId) {
super(application);
mObservableChewToys = repository.loadChewToysById(dogId);
mObservableDog = repository.loadDog(dogId);
}
public LiveData<List<ChewToyEntity>> getChewToys() {
return mObservableChewToys;
}
public LiveData<DogEntity> getDog() {
return mObservableDog;
}
public static class Factory extends ViewModelProvider.NewInstanceFactory {
@NonNull private final Application mApplication;
private final int mDogId;
private final DataRepository mRepository;
public Factory(@NonNull Application application, int dogId) {
mApplication = application;
mDogId = dogId;
mRepository = ((DogApp) application).getRepository();
}
@SuppressWarnings("unchecked")
@Override
@NonNull
public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
return (T) new DogViewModel(mApplication, mRepository, mDogId);
}
}
}
BindingAdapters.java
public class BindingAdapters {
@BindingAdapter("visibleGone")
public static void showHide(View view, boolean show) {
view.setVisibility(show ? View.VISIBLE : View.GONE);
}
}
DogClickCallback.java
public interface DogClickCallback {
void onClick(Dog dog);
}
dao query
@Query("select * from dog_table where id = :dogId")
LiveData<DogEntity> loadDog(int dogId);
DogAdapter.java
public class DogAdapter extends RecyclerView.Adapter<DogAdapter.DogViewHolder> {
private static final String TAG = "\t\tDogAdapter";
@Nullable private final DogClickCallback mDogClickCallback;
List<? extends Dog> mDogList;
public DogAdapter(@Nullable DogClickCallback clickCallback) {
Log.i(TAG, "DogAdapter: public constructor");
mDogClickCallback = clickCallback;
setHasStableIds(true);
}
public void setDogList(final List<? extends Dog> dogList) {
if (mDogList == null) {
mDogList = dogList;
notifyItemRangeInserted(0, dogList.size());
} else {
DiffUtil.DiffResult result =
DiffUtil.calculateDiff(
new DiffUtil.Callback() {
@Override
public int getOldListSize() {
return mDogList.size();
}
@Override
public int getNewListSize() {
return dogList.size();
}
@Override
public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
return mDogList.get(oldItemPosition).getId()
== dogList.get(newItemPosition).getId();
}
@Override
public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
Dog newDog = dogList.get(newItemPosition);
Dog oldDog = mDogList.get(oldItemPosition);
return newDog.getId() == oldDog.getId()
&& TextUtils.equals(newDog.getName(), oldDog.getName());
}
});
mDogList = dogList;
result.dispatchUpdatesTo(this);
}
}
@Override
@NonNull
public DogViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
DogItemBinding binding =
DataBindingUtil.inflate(
LayoutInflater.from(parent.getContext()), R.layout.dog_item, parent, false);
binding.setCallback(mDogClickCallback);
return new DogViewHolder(binding);
}
@Override
public void onBindViewHolder(@NonNull DogViewHolder holder, int position) {
holder.binding.setDog(mDogList.get(position));
holder.binding.executePendingBindings();
}
@Override
public int getItemCount() {
return mDogList == null ? 0 : mDogList.size();
}
@Override
public long getItemId(int position) {
return mDogList.get(position).getId();
}
static class DogViewHolder extends RecyclerView.ViewHolder {
final DogItemBinding binding;
public DogViewHolder(DogItemBinding binding) {
super(binding.getRoot());
this.binding = binding;
}
}
}
(DogEntity 也有 Dog 模型 class,如果有帮助的话)
我试过 Invalidate Caches/Restart,我试过 Clean Project,Rebuild Project。我开始了一个新项目并将我的文件复制到其中。
哦,还有,这是另外一个错误:
import the_derek.dogstuff.databinding.DogFragmentBindingImpl;
它告诉我它无法解析 DogFragmentBindingImpl
我不知道它是如何没有生成的,但我认为这些问题是交织在一起的。我不知道我是否遗漏了任何可能有帮助的代码,请告诉我。
您在此处传递一个 LiveData 对象:
app:product="@{dogViewModel.dog}"
您需要传入:
app:product="@{dogViewModel.dog.value}"
我花了几周或一个月的时间认为“app:product”是 XML 的某种标准短语或惯例。我认为“产品”是一个通用术语,类似于“重力”或“布局”……如果您明白我的意思的话。因为当我发布问题时我是 Android 的新手,我从没想过“app:”之后的术语需要根据数据中的变量进行更改。
<include
layout="@layout/dog_item"
app:dog="@{dogViewModel.dog}" />
这是 binding adapter 错误。如果你在你的 XML 中写 'app:product',你的 kotlin 或 java 类 中必须有绑定适配器,名称为 'product'。例如,对于您的
app:product="@{dogViewModel.dog}"
需要这样的东西:
@BindingAdapter("product")
fun yourFunctionName(yourViewType: YourViewType, data: List<DogEntity>?) {
// your binding code here
}
阅读有关数据绑定和绑定适配器的更多信息。
告诉您 include-tag 中的参数名称必须与包含的布局中使用的变量名称相匹配。
<include
layout="@layout/dog_item"
app:dog="@{dogViewModel.dog}" />
dog_item
<data>
<variable
name="dog"
type="$path.DogClass" />
</data>
绑定时没有通用的参数名称来匹配变量,您可以自己定义名称然后相应地设置它们。
Cannot find a setter for <the_derek.dogstuff.databinding.DogItemBinding app:product> that accepts parameter type 'androidx.lifecycle.LiveData<the_derek.dogstuff.db.entity.DogEntity>' If a binding adapter provides the setter, check that the adapter is annotated correctly and that the parameter type matches.
两天多来,我一直在逐行浏览我的应用程序。我使用 Google 提供的“BasicSample”Android Room 应用程序来模拟我自己的应用程序,但是当我将其包含在我的 dog_fragment.xml
中时出现此错误<include
layout="@layout/dog_item"
app:product="@{dogViewModel.dog}" />
“dog_item”布局(dog_item.xml)用于显示狗的列表,当您单击它时,它将带您进入狗的详细信息屏幕(dog_fragment.xml).没有它,一切都很好,但它缺少在详细信息屏幕中播放的“狗”图块,并且只会显示 chew_toys.
的列表dog_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<import type="android.view.View" />
<variable
name="isLoading"
type="boolean" />
<variable
name="dog"
type="the_derek.dogstuff.viewmodel.DogViewModel" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/cardview_light_background"
android:orientation="vertical">
<include
layout="@layout/dog_item"
app:product="@{dogViewModel.dog}" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/tv_loading_chew_toys"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="@string/loading_chew_toys"
app:visibleGone="@{isLoading}" />
<FrameLayout
android:id="@+id/chew_toys_list_wrapper"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/chew_toy_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="@string/cd_chew_toys_list"
app:layoutManager="LinearLayoutManager"
app:visibleGone="@{!isLoading}" />
</FrameLayout>
</FrameLayout>
</LinearLayout>
</layout>
DogFragment.java
public class DogFragment extends Fragment {
private static final String TAG = "\t\tDogFragment";
private static final String KEY_DOG_ID = "dog_id";
private final ChewToyClickCallback mChewToyClickCallback =
chewToy -> {
// no-op
};
private DogFragmentBinding mBinding;
private ChewToyAdapter mChewToyAdapter;
public static DogFragment forDog(int dogId) {
DogFragment fragment = new DogFragment();
Bundle args = new Bundle();
args.putInt(KEY_DOG_ID, dogId);
fragment.setArguments(args);
return fragment;
}
@Nullable
@Override
public View onCreateView(
@NonNull LayoutInflater inflater,
@Nullable ViewGroup container,
@Nullable Bundle savedInstanceState) {
mBinding = DataBindingUtil.inflate(inflater, R.layout.dog_fragment, container, false);
mChewToyAdapter = new ChewToyAdapter(mChewToyClickCallback);
mBinding.chewToyList.setAdapter(mChewToyAdapter);
return mBinding.getRoot();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
DogViewModel.Factory factory =
new DogViewModel.Factory(
requireActivity().getApplication(), requireArguments().getInt(KEY_DOG_ID));
final DogViewModel model =
new ViewModelProvider(this, factory).get(DogViewModel.class);
mBinding.setLifecycleOwner(getViewLifecycleOwner());
mBinding.setDogViewModel(model);
subscribeToModel(model);
}
private void subscribeToModel(final DogViewModel model) {
model
.getChewToys()
.observe(
getViewLifecycleOwner(),
chewToyEntities -> {
if (chewToyEntities != null) {
mBinding.setIsLoading(false);
mChewToyAdapter.submitList(chewToyEntities);
} else {
mBinding.setIsLoading(true);
}
});
}
@Override
public void onDestroyView() {
mBinding = null;
mChewToyAdapter = null;
super.onDestroyView();
}
}
DogViewModel.java
public class DogViewModel extends AndroidViewModel {
private static final String TAG = "\t\tDogViewModel";
private final LiveData<DogEntity> mObservableDog;
private final LiveData<List<ChewToyEntity>> mObservableChewToys;
public DogViewModel(
@NonNull Application application, DataRepository repository, final int dogId) {
super(application);
mObservableChewToys = repository.loadChewToysById(dogId);
mObservableDog = repository.loadDog(dogId);
}
public LiveData<List<ChewToyEntity>> getChewToys() {
return mObservableChewToys;
}
public LiveData<DogEntity> getDog() {
return mObservableDog;
}
public static class Factory extends ViewModelProvider.NewInstanceFactory {
@NonNull private final Application mApplication;
private final int mDogId;
private final DataRepository mRepository;
public Factory(@NonNull Application application, int dogId) {
mApplication = application;
mDogId = dogId;
mRepository = ((DogApp) application).getRepository();
}
@SuppressWarnings("unchecked")
@Override
@NonNull
public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
return (T) new DogViewModel(mApplication, mRepository, mDogId);
}
}
}
BindingAdapters.java
public class BindingAdapters {
@BindingAdapter("visibleGone")
public static void showHide(View view, boolean show) {
view.setVisibility(show ? View.VISIBLE : View.GONE);
}
}
DogClickCallback.java
public interface DogClickCallback {
void onClick(Dog dog);
}
dao query
@Query("select * from dog_table where id = :dogId")
LiveData<DogEntity> loadDog(int dogId);
DogAdapter.java
public class DogAdapter extends RecyclerView.Adapter<DogAdapter.DogViewHolder> {
private static final String TAG = "\t\tDogAdapter";
@Nullable private final DogClickCallback mDogClickCallback;
List<? extends Dog> mDogList;
public DogAdapter(@Nullable DogClickCallback clickCallback) {
Log.i(TAG, "DogAdapter: public constructor");
mDogClickCallback = clickCallback;
setHasStableIds(true);
}
public void setDogList(final List<? extends Dog> dogList) {
if (mDogList == null) {
mDogList = dogList;
notifyItemRangeInserted(0, dogList.size());
} else {
DiffUtil.DiffResult result =
DiffUtil.calculateDiff(
new DiffUtil.Callback() {
@Override
public int getOldListSize() {
return mDogList.size();
}
@Override
public int getNewListSize() {
return dogList.size();
}
@Override
public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
return mDogList.get(oldItemPosition).getId()
== dogList.get(newItemPosition).getId();
}
@Override
public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
Dog newDog = dogList.get(newItemPosition);
Dog oldDog = mDogList.get(oldItemPosition);
return newDog.getId() == oldDog.getId()
&& TextUtils.equals(newDog.getName(), oldDog.getName());
}
});
mDogList = dogList;
result.dispatchUpdatesTo(this);
}
}
@Override
@NonNull
public DogViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
DogItemBinding binding =
DataBindingUtil.inflate(
LayoutInflater.from(parent.getContext()), R.layout.dog_item, parent, false);
binding.setCallback(mDogClickCallback);
return new DogViewHolder(binding);
}
@Override
public void onBindViewHolder(@NonNull DogViewHolder holder, int position) {
holder.binding.setDog(mDogList.get(position));
holder.binding.executePendingBindings();
}
@Override
public int getItemCount() {
return mDogList == null ? 0 : mDogList.size();
}
@Override
public long getItemId(int position) {
return mDogList.get(position).getId();
}
static class DogViewHolder extends RecyclerView.ViewHolder {
final DogItemBinding binding;
public DogViewHolder(DogItemBinding binding) {
super(binding.getRoot());
this.binding = binding;
}
}
}
(DogEntity 也有 Dog 模型 class,如果有帮助的话) 我试过 Invalidate Caches/Restart,我试过 Clean Project,Rebuild Project。我开始了一个新项目并将我的文件复制到其中。 哦,还有,这是另外一个错误:
import the_derek.dogstuff.databinding.DogFragmentBindingImpl;
它告诉我它无法解析 DogFragmentBindingImpl 我不知道它是如何没有生成的,但我认为这些问题是交织在一起的。我不知道我是否遗漏了任何可能有帮助的代码,请告诉我。
您在此处传递一个 LiveData 对象:
app:product="@{dogViewModel.dog}"
您需要传入:
app:product="@{dogViewModel.dog.value}"
我花了几周或一个月的时间认为“app:product”是 XML 的某种标准短语或惯例。我认为“产品”是一个通用术语,类似于“重力”或“布局”……如果您明白我的意思的话。因为当我发布问题时我是 Android 的新手,我从没想过“app:”之后的术语需要根据数据中的变量进行更改。
<include
layout="@layout/dog_item"
app:dog="@{dogViewModel.dog}" />
这是 binding adapter 错误。如果你在你的 XML 中写 'app:product',你的 kotlin 或 java 类 中必须有绑定适配器,名称为 'product'。例如,对于您的
app:product="@{dogViewModel.dog}"
需要这样的东西:
@BindingAdapter("product")
fun yourFunctionName(yourViewType: YourViewType, data: List<DogEntity>?) {
// your binding code here
}
阅读有关数据绑定和绑定适配器的更多信息。
<include
layout="@layout/dog_item"
app:dog="@{dogViewModel.dog}" />
dog_item
<data>
<variable
name="dog"
type="$path.DogClass" />
</data>
绑定时没有通用的参数名称来匹配变量,您可以自己定义名称然后相应地设置它们。