在Java中数组列表意向额外 [英] Array List Intent extra in Java

问题描述

我想跳过我的的ArrayList 到意图。但我不能找到额外写什么？任何get方法我越来越喜欢错误不适用于字符串。

项目详细信息：

 公共类ItemDetails {

公共字符串的getName（）{
    返回名称;
}
公共无效setname可以（字符串名称）{
    this.name =名称;
}
公共字符串getItemDescription（）{
    返回itemDescription;
}
公共无效setItemDescription（字符串itemDescription）{
    this.itemDescription = itemDescription;
}
公共字符串用getPrice（）{
    返回的价格;
}
公共无效setPrice（字符串价格）{
    this.price =价格;
}
公众诠释getImageNumber（）{
    返回imageNumber;
}
公共无效setImageNumber（INT imageNumber）{
    this.imageNumber = imageNumber;
}

公众诠释getVideoNumber（）{
    返回videoNumber;
}
公共无效setVideoNumber（INT videoNumber）{
    this.videoNumber = videoNumber;
}

公共无效setChild（ArrayList中＆LT; ItemDetails＆GT; item_child）
{
    this.item_child = item_child;
}
公众的ArrayList＆LT; ItemDetails＆GT; getChild（）
{
    返回this.item_child;
}
公共无效的setParent（ArrayList中＆LT; ItemDetails＆GT; item_parent）
{
    this.item_parent = item_parent;
}
公众的ArrayList＆LT; ItemDetails＆GT;的getParent（）
{
    返回this.item_parent;
}



私人字符串名称;
私人字符串itemDescription;
私人字符串的价格;
私人诠释imageNumber;
私人诠释videoNumber;
私人的ArrayList＆LT; ItemDetails＆GT; item_child;
    私人的ArrayList＆LT; ItemDetails＆GT; item_parent;
}
 

我的类：

 静态类ViewHolder {
    TextView的txt_itemName;
    TextView的txt_itemDescription;
    TextView的txt_itemPrice;
    ImageView的itemImage;
    ArrayList的＆LT; ItemDetails＆GT; item_parent;
    ArrayList的＆LT; ItemDetails＆GT; item_child;
}
 

我的putExtra：

  intObj.putExtra（exerciselist，obj_itemDetails.getChild（））;
 

GetChild功能：

 公开的ArrayList＆LT; ItemDetails＆GT; getChild（）
{
   返回this.item_child;
}
 

但我找不到我怎么写来获得ArrayList的？

 的ArrayList＆LT; ItemDetails＆GT; child1 = getIntent（）。?????????
 

解决方案

  

但我找不到我怎么写得到的ArrayList

简短的回答：你不能。你只能通过的ArrayList＆LT;字符串＆GT; ，然后用

检索

  getIntent（）getStringArrayListExtra（键）。
 

但是。如果您想通过意图进行自定义对象的对象必须实现：

• Parcelable接口 或< A HREF =htt​​p://developer.android.com/reference/java/io/Serializable.html> Serializable接口

您可以选择其中之一。这两部作品都相同，但有不同的实现。

Parcelable接口：

如果您选择Parcelable界面，你的 ItemDetails 类必须实现Parcelable。然后，你可以把它看成

  intent.putParcelableArrayListExtra（钥匙，值）;
 

和检索它的：

  getIntent（）getParcelableArrayListExtra（键）。
 

我不会写你Parcelable实现，因为它需要更多一点的code。这里是很好的例子。

Serializable接口：

如果您选择Serializable接口，我建议你创建命名为实例类ItemDetailsWrapper抚慰你的的ArrayList（S）＆LT; ItemDetails＆GT;

这两种即ItemDetailsWrapper和ItemDetails类必须实现Serializable接口。现在，您可以通过意图通过这样的：

  getIntent（）putExtra。（钥匙，＆LT; serializableClass＆GT;）; //存储
。getIntent（）getSerializableExtra（钥匙）; //检索
 

实施例：

 公共类ItemDetailsWrapper实现Serializable {

    私有静态最后长的serialVersionUID = 1L;
    私人的ArrayList＆LT; ItemDetails＆GT; itemDetails;

    公共ItemDetailsWrapper（ArrayList中＆LT; ItemDetails＆GT;项目）{
        this.itemDetails =项目;
    }

    公众的ArrayList＆LT; ItemDetails＆GT; getItemDetails（）{
        返回itemDetails;
    }
}

公共类ItemDetails实现Serializable {

    私有静态最后长的serialVersionUID = 1L;

    // getter方法​​，setter方法​​和属性
}
 

和如何通过活动：

  ItemDetailsWrapper包装=新ItemDetailsWrapper（名单）;
意图I =新的意图（小于背景＆GT中，＆lt; targetActivity＆GT;）;
i.putExtra（目标文件，包装）; // i.putExtra（目标文件，新ItemDetailsWrapper（列表））;
//检索
ItemDetailsWrapper包=
                    （ItemDetailsWrapper）getIntent（）getSerializableExtra（物镜）;
ArrayList的＆LT; ItemDetails＆GT;表= wrap.getItemDetails（）;
 

I am trying to skip my ArrayList through Intent. But I cannot find what to write in extra? Any get methods I am getting errors like "not applicable for string."

Item Details:

public class ItemDetails {

public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getItemDescription() {
    return itemDescription;
}
public void setItemDescription(String itemDescription) {
    this.itemDescription = itemDescription;
}
public String getPrice() {
    return price;
}
public void setPrice(String price) {
    this.price = price;
}
public int getImageNumber() {
    return imageNumber;
}
public void setImageNumber(int imageNumber) {
    this.imageNumber = imageNumber;
}

public int getVideoNumber() {
    return videoNumber;
}
public void setVideoNumber(int videoNumber) {
    this.videoNumber = videoNumber;
}

public void setChild(ArrayList<ItemDetails> item_child)
{
    this.item_child = item_child;
}
public ArrayList<ItemDetails> getChild()
{
    return this.item_child;
}
public void setParent(ArrayList<ItemDetails> item_parent)
{
    this.item_parent = item_parent;
}
public ArrayList<ItemDetails> getParent()
{
    return this.item_parent;
}



private String name ;
private String itemDescription;
private String price;
private int imageNumber;
private int videoNumber;
private ArrayList<ItemDetails> item_child;
    private ArrayList<ItemDetails> item_parent; 
}

My class:

static class ViewHolder {
    TextView txt_itemName;
    TextView txt_itemDescription;
    TextView txt_itemPrice;
    ImageView itemImage;
    ArrayList<ItemDetails> item_parent;
    ArrayList<ItemDetails> item_child;
}

My putExtra:

intObj.putExtra("exerciselist",obj_itemDetails.getChild());

GetChild function :

public ArrayList<ItemDetails> getChild()
{
   return this.item_child;
}

But I cannot find how am I supposed to write to get arrayList?

ArrayList<ItemDetails> child1 = getIntent().?????????

解决方案

But i cannot find how am ı supposed to write to get arrayList

Short answer: you can't. You can only pass ArrayList<String> and then retrieve it with

getIntent().getStringArrayListExtra("key");

But. If you want to pass custom objects via Intent your objects have to implement:

• Parcelable interface or Serializable interface

You can choose one of them. Both works same but have different implementations.

Parcelable interface:

If you choose Parcelable interface, your ItemDetails class have to implement Parcelable. Then you can put it as

intent.putParcelableArrayListExtra("key", value);

and retrieve it as:

getIntent().getParcelableArrayListExtra("key");

I won't write you Parcelable implementation because it requires a little more code. Here is nice example.

Serializable interface:

If you choose Serializable interface i suggest you to create class named for instance ItemDetailsWrapper that will wrap your ArrayList(s)<ItemDetails>

Both i.e. ItemDetailsWrapper and ItemDetails class have to implement Serializable interface. Now you are able to pass it via Intent like this:

getIntent().putExtra("key", <serializableClass>); // storing 
getIntent().getSerializableExtra("key"); // retrieving

Example of implementation:

public class ItemDetailsWrapper implements Serializable {

    private static final long serialVersionUID = 1L;
    private ArrayList<ItemDetails> itemDetails;

    public ItemDetailsWrapper(ArrayList<ItemDetails> items) {
        this.itemDetails = items;
    }

    public ArrayList<ItemDetails> getItemDetails() {
        return itemDetails;
    }
}

public class ItemDetails implements Serializable {

    private static final long serialVersionUID = 1L;

    // getters, setters and properties
}

And how to pass through Activities:

ItemDetailsWrapper wrapper = new ItemDetailsWrapper(list);
Intent i = new Intent(<context>, <targetActivity>);
i.putExtra("obj", wrapper); // i.putExtra("obj", new ItemDetailsWrapper(list));
// retrieving 
ItemDetailsWrapper wrap = 
                    (ItemDetailsWrapper) getIntent().getSerializableExtra("obj");
ArrayList<ItemDetails> list = wrap.getItemDetails();

这篇关于在Java中数组列表意向额外的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！