尝试在 Cast.writetoParcel 的空对象引用上调用虚拟方法“int.java.lang.Integer.intValue()”
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StackOverFlow
Attempt to invoke virtual method 'int.java.lang.Integer.intValue()' on a null object reference at Cast.writetoParcel
提问by Lakshya Punhani
Getting Error FATAL EXCEPTION: main Process: com.example.wuntu.tv_bucket, PID: 3895 java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Integer.intValue()' on a null object reference at com.example.wuntu.tv_bucket.Models.Cast.writeToParcel(Cast.java:136) at android.os.Parcel.writeParcelable(Parcel.java:1437) at android.os.Parcel.writeValue(Parcel.java:1343) at android.os.Parcel.writeList(Parcel.java:759) at android.os.Parcel.writeValue(Parcel.java:1365) at android.os.Parcel.writeArrayMapInternal(Parcel.java:686) at android.os.BaseBundle.writeToParcelInner(BaseBundle.java:1330) at android.os.Bundle.writeToParcel(Bundle.java:1079) at android.os.Parcel.writeBundle(Parcel.java:711) at android.content.Intent.writeToParcel(Intent.java:8790) at android.app.ActivityManagerProxy.startActivity(ActivityManagerNative.java:3112) at android.app.Instrumentation.execStartActivity(Instrumentation.java:1541) at android.app.Activity.startActivityForResult(Activity.java:4284) at android.support.v4.app.BaseFragmentActivityJB.startActivityForResult(BaseFragmentActivityJB.java:50) at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:79) at android.app.Activity.startActivityForResult(Activity.java:4231) at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:859) at android.app.Activity.startActivity(Activity.java:4568) at android.app.Activity.startActivity(Activity.java:4536) at com.example.wuntu.tv_bucket.Adapters.CastDetailAdapter$1.onClick(CastDetailAdapter.java:124) at android.view.View.performClick(View.java:5698) at android.widget.TextView.performClick(TextView.java:10908) at android.view.View$PerformClick.run(View.java:22557) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7231) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
获取错误 FATAL EXCEPTION: main Process: com.example.wuntu.tv_bucket, PID: 3895 java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Integer.intValue()' on a null object reference at com. example.wuntu.tv_bucket.Models.Cast.writeToParcel(Cast.java:136) at android.os.Parcel.writeParcelable(Parcel.java:1437) at android.os.Parcel.writeValue(Parcel.java:1343) 在 android.os.Parcel.writeList(Parcel.java:759) 在 android.os.Parcel.writeValue(Parcel.java:1365) 在 android.os.Parcel.writeArrayMapInternal(Parcel.java:686) 在 android。 os.BaseBundle.writeToParcelInner(BaseBundle.java:1330) at android.os.Bundle.writeToParcel(Bundle.java:1079) at android.os.Parcel.writeBundle(Parcel.java:711) 在 android.content.Intent.writeToParcel(Intent.java:8790) 在 android.app.ActivityManagerProxy.startActivity(ActivityManagerNative.java:3112) 在 android.app.Instrumentation.execStartActivity(Instrumentation.java:1541) 在 android。 app.Activity.startActivityForResult(Activity.java:4284) 在 android.support.v4.app.BaseFragmentActivityJB.startActivityForResult(BaseFragmentActivityJB.java:50) 在 android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:79) 在 android.app.Activity.startActivityForResult(Activity.java:4231) 在 android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity) .java:859) 在 android.app.Activity.startActivity(Activity.java:4568) 在 android.app.Activity.startActivity(Activity.java:4536) 在 com.example.wuntu.tv_bucket.Adapters.CastDetailAdapter$1.onClick(CastDetailAdapter.java:124) 在 android.view.View.performClick(View.java:5698) 在 android.widget.TextView.performClick(TextView. java:10908) 在 android.view.View$PerformClick.run(View.java:22557) 在 android.os.Handler.handleCallback(Handler.java:739) 在 android.os.Handler.dispatchMessage(Handler.java:95) 在 android.os.Looper.loop(Looper.java:158) 在 android.app.ActivityThread.main(ActivityThread.java:7231) 在 java.lang.reflect.Method.invoke(Native Method) 在 com.android .internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)158) 在 android.app.ActivityThread.main(ActivityThread.java:7231) 在 java.lang.reflect.Method.invoke(Native Method) 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:第 1230 章158) 在 android.app.ActivityThread.main(ActivityThread.java:7231) 在 java.lang.reflect.Method.invoke(Native Method) 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:第 1230 章invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
Getting error in sending arraylistof object from adapter to other activity. I wanna send my arraylistfrom onBindViewHoldermethod of Adapter to another activity but its is showing null exception error on the Cast Class in writetoParcelMethod. How to send arraylistproperly?
将arraylist对象从适配器发送到其他活动时出错。我想送我arraylist从onBindViewHolder适配器的方法到另一个活动，但它正显示出对在演员类零异常错误writetoParcel的方法。如何arraylist正确发送？
Cast Class
演员班
public class Cast implements Parcelable {
@SerializedName("cast_id")
@Expose
private Integer castId;
@SerializedName("character")
@Expose
private String character;
@SerializedName("credit_id")
@Expose
private String creditId;
@SerializedName("gender")
@Expose
private Integer gender;
@SerializedName("id")
@Expose
private Integer id;
@SerializedName("name")
@Expose
private String name;
@SerializedName("order")
@Expose
private Integer order;
@SerializedName("profile_path")
@Expose
private String profilePath;
public Cast(){
}
protected Cast(Parcel in) {
character = in.readString();
id = in.readInt();
name = in.readString();
profilePath = in.readString();
}
public static final Creator<Cast> CREATOR = new Creator<Cast>() {
@Override
public Cast createFromParcel(Parcel in) {
return new Cast(in);
}
@Override
public Cast[] newArray(int size) {
return new Cast[size];
}
};
public Integer getCastId() {
return castId;
}
public void setCastId(Integer castId) {
this.castId = castId;
}
public String getCharacter() {
return character;
}
public void setCharacter(String character) {
this.character = character;
}
public String getCreditId() {
return creditId;
}
public void setCreditId(String creditId) {
this.creditId = creditId;
}
public Integer getGender() {
return gender;
}
public void setGender(Integer gender) {
this.gender = gender;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getOrder() {
return order;
}
public void setOrder(Integer order) {
this.order = order;
}
public String getProfilePath() {
return profilePath;
}
public void setProfilePath(String profilePath) {
this.profilePath = profilePath;
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel parcel, int i)
{
parcel.writeString(name);
parcel.writeString(profilePath);
parcel.writeString(character);
parcel.writeInt(id);
}
}
CastDetailAdapter Class
CastDetailAdapter 类
public class CastDetailAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private ArrayList<Cast> detailArrayList = new ArrayList<>() ;
private UrlConstants urlConstants = UrlConstants.getSingletonRef();
private Cast cast;
private final int VIEW_ITEM = 0;
private final int VIEW_PROG = 1;
private Context context;
MovieView a;
ArrayList<Cast> FullArrayList = new ArrayList<>();
public CastDetailAdapter(MovieView movieView, ArrayList<Cast> detailArrayList,ArrayList<Cast> subCastArrayList)
{
a = movieView;
this.detailArrayList = subCastArrayList;
this.FullArrayList = detailArrayList;
}
public class MyViewHolder1 extends RecyclerView.ViewHolder
{
ImageView cast_profile_picture;
TextView cast_name,cast_character_name;
public MyViewHolder1(View view)
{
super(view);
cast_profile_picture = (ImageView) view.findViewById(R.id.thumbnail);
cast_name = (TextView) view.findViewById(R.id.title);
cast_character_name = (TextView) view.findViewById(R.id.count);
}
}
public class FooterViewHolder1 extends RecyclerView.ViewHolder
{
TextView view_more;
public FooterViewHolder1(View itemView) {
super(itemView);
view_more = (TextView) itemView.findViewById(R.id.view_more);
}
}
@Override
public int getItemViewType(int position) {
if (isPositionItem(position))
return VIEW_ITEM;
return VIEW_PROG;
}
private boolean isPositionItem(int position) {
return position != getItemCount() -1;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
{
context = parent.getContext();
if (viewType == VIEW_ITEM)
{
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.cast_details, parent, false);
return new MyViewHolder1(v);
} else if (viewType == VIEW_PROG){
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.footer_layout_movie_details, parent, false);
return new FooterViewHolder1(v);
}
return null;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position)
{
if(holder instanceof MyViewHolder1)
{
cast = detailArrayList.get(position);
((MyViewHolder1)holder).cast_character_name.setText(cast.getCharacter());
((MyViewHolder1)holder).cast_name.setText(cast.getName());
String url3 = urlConstants.URL_Image + cast.getProfilePath();
Picasso.with(context)
.load(url3)
.into(((MyViewHolder1)holder).cast_profile_picture);
}
else if (holder instanceof FooterViewHolder1)
{
((FooterViewHolder1)holder).view_more.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view)
{
Intent intent = new Intent(context,CastViewActivity.class);
intent.putParcelableArrayListExtra("LIST",FullArrayList);
context.startActivity(intent);
}
});
}
}
@Override
public int getItemCount() {
return this.detailArrayList.size();
}
}
回答by Ben P.
In your writeToParcel()method, you have
在你的writeToParcel()方法中，你有
parcel.writeInt(id);
Since idis Integer, this is going to auto-unbox id. If idis null, this auto-unboxing will throw a NullPointerException.
由于idis Integer，这将自动拆箱id。如果id为 null，则此自动拆箱将抛出NullPointerException.
Since there is no Parcel.writeInteger()method, you're going to have to record whether or not idis null in a separate write. Something like:
由于没有Parcel.writeInteger()方法，您将不得不id在单独的写入中记录是否为空。就像是：
if (id == null) {
dest.writeInt(0);
}
else {
dest.writeInt(1);
dest.writeInt(id);
}
And to read it back out:
并读出它：
int hasId = in.readInt();
if (hasId == 1) {
id = in.readInt();
}
else {
id = null;
}
回答by Maarten van Tjonger
The order in which you read the values from the parcel has to be the same as the order it was written to it.
您从包裹中读取值的顺序必须与写入包裹的顺序相同。
Try:
尝试：
protected Cast(Parcel in) {
name = in.readString();
profilePath = in.readString();
character = in.readString();
id = in.readInt();
}
