android - 尝试在 json 中的空对象引用上调用虚拟方法 'void android.widget.TextView.setText(java.lang.CharSequence)'
问题描述
我正在尝试从 json 文件中调用折扣价和折扣价。
Json 内容是。
[
{
"Menu_ID":"63",
"Menu_name":"Who knows that he is hero? whole of product discre",
"Price":"1800",
"Discounted_Price":"180",
"Discounted_Value":"13",
"Menu_image":"upload\/images\/9489-2018-06-11.png"
},
{
"Menu_ID":"62",
"Menu_name":"Who knows that he is hero?",
"Price":"190",
"Discounted_Price":"90",
"Discounted_Value":"9",
"Menu_image":"upload\/images\/0459-2018-06-10.png"
}
]
我正在使用 recyclerview 来显示我的应用程序中的所有内容。
我实施recyclerview的片段
ArrayList<Double> Discounted_Price = new ArrayList<Double>();
ArrayList<String> Discounted_Value = new ArrayList<String>();
公共无效PrsJsonRea(JSONArray数组){
for(int i = 0; i<array.length(); i++) {
SecondPojoListData getJsonRecAdap = new SecondPojoListData();
JSONObject json = null;
try {
json = array.getJSONObject(i);
getJsonRecAdap.setDiscPrice3(json.getString("Discounted_Price"));
getJsonRecAdap.setDiscValue3(json.getString("Discounted_Value"));
Menu_ID3.add(json.getLong("Menu_ID"));
// Adding image title name in array to display on RecyclerView click event.
Discounted_Value5.add(json.getString("Discounted_Value"));
Discounted_Price5.add(Double.valueOf(formatData.format(json.getDouble("Discounted_Price"))));
} catch (JSONException e) {
e.printStackTrace();
}
recDataAdap.add(getJsonRecAdap);
}
madap2 = new FrontHorizontalListAdapter(recDataAdap,getContext());
secondrecyclerView.setAdapter(madap2);
}
适配器类
@Override
public void onBindViewHolder(ViewHolder Viewholder, int position) {
SecondPojoListData dataAdapterOBJ = dataAdapters.get(position);
Viewholder.discountedvalue.setText(dataAdapterOBJ.getDiscValue3());
Viewholder.discountedprice.setText(dataAdapterOBJ.getDiscPrice3());
}
类 ViewHolder 扩展 RecyclerView.ViewHolder{
public TextView discountedvalue, discountedprice;
public
public ViewHolder(View itemView) {
super(itemView);
discountedprice = (TextView) itemView.findViewById(R.id.DiscountPrice);
discountedvalue = (TextView) itemView.findViewById(R.id.DiscountValue);
Menuprice = (TextView) itemView.findViewById(R.id.itemprice);
}
}
xml布局
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="10sp"
android:textColor="@color/secondary_text"
android:maxLines="1"
android:gravity="left|center_vertical"
android:id="@+id/DiscountValue"
android:padding="5dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="10sp"
android:textColor="@color/secondary_text"
android:maxLines="1"
android:gravity="left|center_vertical"
android:id="@+id/DiscountPrice"
android:padding="5dp"/>
错误信息。
06-12 09:07:11.981 32633 32633 E AndroidRuntime java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
06-12 09:07:11.981 32633 32633 E AndroidRuntime at com.androbaron.ecommerce.adapters.FrontHorizontalListAdapter.onBindViewHolder(FrontHorizontalListAdapter.java:83)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at com.androbaron.ecommerce.adapters.FrontHorizontalListAdapter.onBindViewHolder(FrontHorizontalListAdapter.java)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:5217)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:5250)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4487)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4363)
06-12 09:07:11.981 32633 32633 E AndroidRuntime at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:1961)
其他一切正常工作都接受折扣价和折扣价
有人帮我解决这个错误吗?
解决方案
您的错误是 aNullPointerException
因为TextView
您中引用的 s 之一ViewHolder
为空。在创建时查看您正在膨胀的布局,ViewHolder
以了解为什么您的引用 ID 不在您绑定的 ItemView 中。
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