我有一个 android 项目,我有一个类。在该类中是 ArrayList<Choices>
.我将获取一些 XML,将其解析出来,然后从中生成对象,然后将其传递给另一个 Activity 。我为此选择 Parcelable。
Parcelable 是一个不错的选择吗?我做的一切正确吗?我对 Parcelable 并不熟悉。我的 ArrayList 是我在这个类中创建的另一个类。它会正确地将对象的 ArrayList 传递给 Parcel,而不是扩展 Parcelable 和其他东西吗?
import java.util.ArrayList;
import android.os.Parcel;
import android.os.Parcelable;
import android.support.v4.os.ParcelableCompat;
public class Question implements Parcelable{
String id;
String text;
String image;
ArrayList<Choices> CHOICES;
public Question(String id, String text, String image) {
super();
this.id = id;
this.text = text;
this.image = image;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public String getImage() {
return image;
}
public void setImage(String image) {
this.image = image;
}
@Override
public String toString() {
return "Question [id=" + id + ", text=" + text + ", image=" + image
+ "]";
}
// Answer Choices class
class Choices {
boolean isCorrect;
String choice;
public Choices(boolean isCorrect, String choice) {
this.isCorrect = isCorrect;
this.choice = choice;
}
public String getChoice() {
return choice;
}
public boolean getIsCorrect() {
return isCorrect;
}
@Override
public String toString() {
return "Choices [isCorrect=" + isCorrect + ", choice=" + choice
+ "]";
}
}
public static final Parcelable.Creator<Question> CREATOR = new Parcelable.Creator<Question>() {
@Override
public Question createFromParcel(Parcel in) {
return new Question(in);
}
@Override
public Question[] newArray(int size) {
return new Question[size];
}
};
@Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(id);
dest.writeString(text);
dest.writeString(image);
dest.writeList(CHOICES);
}
private Question(Parcel in) {
this.id = in.readString();
this.text = in.readString();
this.image = in.readString();
this.CHOICES = in.readArrayList(Choices.class.getClassLoader());
}
}
感谢您的帮助!
最佳答案
如果您需要在 Activity 之间传递 ArrayList
,那么我也会实现 Parcelable
,因为我猜没有其他方法。
但是,我认为您不需要那么多 getter 和 setter。这是实现 Parcelable
的 Question
类:
public class Question implements Parcelable {
public String id;
public String text;
public String image;
public ArrayList<Choice> choices;
/**
* Constructs a Question from values
*/
public Question (String id, String text, String image, ArrayList<Choice> choices) {
this.id = id;
this.text = text;
this.image = image;
this.choices = choices;
}
/**
* Constructs a Question from a Parcel
* @param parcel Source Parcel
*/
public Question (Parcel parcel) {
this.id = parcel.readString();
this.text = parcel.readString();
this.image = parcel.readString();
this.choices = parcel.readArrayList(null);
}
@Override
public int describeContents() {
return 0;
}
// Required method to write to Parcel
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(id);
dest.writeString(text);
dest.writeString(image);
dest.writeList(choices);
}
// Method to recreate a Question from a Parcel
public static Creator<Question> CREATOR = new Creator<Question>() {
@Override
public Question createFromParcel(Parcel source) {
return new Question(source);
}
@Override
public Question[] newArray(int size) {
return new Question[size];
}
};
}
关于Android 类 Parcelable 与 ArrayList,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22446359/