任何人都可以帮助我！
我是一个新的开发人员收到此错误。我试图通过片段中的数据绑定来填充带有firebase的recyclerview。
ProductListFragment.java
public class ProductListFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
RecyclerView recyclerView = (RecyclerView) inflater.inflate(R.layout.recycler_view, container, false);
FirebaseRecyclerAdapter adapter;
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
Firebase mFirebaseRef = new Firebase(Constants.FIREBASE_URL).child("subcategories").child("abc");
adapter = new FirebaseRecyclerAdapter<Product, ViewHolder>(
Product.class, R.layout.fragment_list_product, ViewHolder.class, mFirebaseRef) {
@Override
protected void populateViewHolder(ViewHolder viewHolder, Product product, int i) {
FragmentProductListBinding binding = viewHolder.getBinding();
binding.setProduct(product);
}
};
recyclerView.setAdapter(adapter);
return recyclerView;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
FragmentProductListBinding binding;
public ViewHolder (View rootView) {
super(rootView);
binding = DataBindingUtil.bind(rootView);
}
public FragmentProductListBinding getBinding() {
return binding;
}
}
}
Product.java包含POJO
public class Product extends BaseObservable {
public String productTitle;
public String productUnit;
public String productMRP;
public String productSellingPrice;
public String productDescription;
public Product() {
}
@Bindable
public String getProductUnit() {
return productUnit;
}
public void setProductUnit(String productUnit) {
this.productUnit = productUnit;
}
@Bindable
public String getProductMRP() {
return productMRP;
}
public void setProductMRP(String productMRP) {
this.productMRP = productMRP;
}
@Bindable
public String getProductSellingPrice() {
return productSellingPrice;
}
public void setProductSellingPrice(String productSellingPrice) {
this.productSellingPrice = productSellingPrice;
}
@Bindable
public String getProductDescription() {
return productDescription;
}
public void setProductDescription(String productDescription) {
this.productDescription = productDescription;
}
@Bindable
public String getProductTitle() {
return productTitle;
}
public void setProductTitle(String productTitle) {
this.productTitle = productTitle;
}
}
fragment_list_product.xml
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable name="Product" type="com.abc.www.abc.model.Product"/>
</data>
<RelativeLayout
android:padding="@dimen/activity_horizontal_margin"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="@+id/product_image"
android:layout_width="40dp"
android:layout_height="40dp"
android:scaleType="centerCrop"
android:src="@drawable/ic_twitter"
android:contentDescription="@string/product_list_image_content_description"/>
<TextView
android:id="@+id/product_mrp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/colorPrimary"
android:ellipsize="end"
android:singleLine="true"
android:text="@{Product.productMRP}"
android:textAppearance="?attr/textAppearanceListItem"
android:textSize="14sp"
android:layout_gravity="center"
android:layout_below="@+id/product_title"
android:layout_toRightOf="@+id/product_image"
android:layout_toEndOf="@+id/product_image" />
<TextView
android:id="@+id/product_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginStart="16dp"
android:layout_toRightOf="@+id/product_image"
android:layout_toEndOf="@+id/product_image"
android:layout_marginEnd="16dp"
android:text="@{Product.productTitle}"
android:textAppearance="?attr/textAppearanceListItem"
android:textSize="16sp"
android:layout_gravity="top" />
<TextView
android:id="@+id/product_selling_price"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/colorPrimary"
android:ellipsize="end"
android:singleLine="true"
android:text="@{Product.productSellingPrice}"
android:textAppearance="?attr/textAppearanceListItem"
android:textSize="14sp"
android:layout_gravity="center"
android:layout_below="@+id/product_title"
android:layout_toRightOf="@+id/product_mrp"
android:layout_toEndOf="@+id/product_mrp" />
</RelativeLayout>
这是我得到的错误。
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.abc.www.abc, PID: 1894
com.firebase.client.FirebaseException: Failed to bounce to type
at com.firebase.client.DataSnapshot.getValue(DataSnapshot.java:183)
at com.firebase.ui.FirebaseRecyclerAdapter.parseSnapshot(FirebaseRecyclerAdapter.java:161)
at com.firebase.ui.FirebaseRecyclerAdapter.getItem(FirebaseRecyclerAdapter.java:150)
at com.firebase.ui.FirebaseRecyclerAdapter.onBindViewHolder(FirebaseRecyclerAdapter.java:190)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:5453)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:5486)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4723)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4599)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:1988)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1384)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1347)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:574)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3003)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:2881)
at android.support.v7.widget.RecyclerView.consumePendingUpdateOperations(RecyclerView.java:1457)
at android.support.v7.widget.RecyclerView.access$400(RecyclerView.java:147)
at android.support.v7.widget.RecyclerView$1.run(RecyclerView.java:285)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:603)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5422)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Can not instantiate value of type [simple type, class com.abc.www.abc.model.Product] from String value; no single-String constructor/factory method
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator._createFromStringFallbacks(StdValueInstantiator.java:428)
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromString(StdValueInstantiator.java:299)
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromString(BeanDeserializerBase.java:1056)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:136)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:123)
at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:2888)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2034)
at com.firebase.client.DataSnapshot.getValue(DataSnapshot.java:181)
at com.firebase.ui.FirebaseRecyclerAdapter.parseSnapshot(FirebaseRecyclerAdapter.java:161)
at com.firebase.ui.FirebaseRecyclerAdapter.getItem(FirebaseRecyclerAdapter.java:150)
at com.firebase.ui.FirebaseRecyclerAdapter.onBindViewHolder(FirebaseRecyclerAdapter.java:190)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:5453)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:5486)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4723)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4599)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:1988)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1384)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1347)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:574)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3003)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:2881)
at android.support.v7.widget.RecyclerView.consumePendingUpdateOperations(RecyclerView.java:1457)
at android.support.v7.widget.RecyclerView.access$400(RecyclerView.java:147)
at android.support.v7.widget.RecyclerView$1.run(RecyclerView.java:285)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:603)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5422)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
这是我试图从firebase获取的数据库。
subcategories{
abc{
product-description:"xxadasccdcnsdcnsdc"
product-mrp: 100
product-selling-price: 80
product-title:"Name"
product-unit: "100 meter"}
}
答案 0 :(得分：1)
在变量之上使用@JsonProperty（“product-description”）将其与数据库匹配。
@JsonProperty("product-title")
public String productTitle;
@JsonProperty("product-unit")
public String productUnit;
问题在于Firebase Android客户端用于序列化/反序列化JSON的Jackson库与POJO和DB中的属性名称不匹配
答案 1 :(得分：1)
在BaseObservable.class顶部使用@JsonIgnoreProperties（ignoreUnknown = true）
@JsonIgnoreProperties(ignoreUnknown = true)
public class Product extends BaseObservable {
public Product() {
}