I am currently trying to pass an ArrayList of objects from one activity to another. After much searching, I saw that you could pass things as parcels. Here is what I ended up doing:
public class PartsList extends ArrayList<Part> implements Parcelable {
public PartsList(){
}
public PartsList(Parcel in){
}
@SuppressWarnings("unchecked")
public static final Parcelable.Creator CREATOR = new Parcelable.Creator() {
public PartsList createFromParcel(Parcel in) {
return new PartsList(in);
}
public Object[] newArray(int arg0) {
return null;
}
};
private void readFromParcel(Parcel in) {
this.clear();
// read the list size
int size = in.readInt();
// order of the in.readString is fundamental
// it must be ordered as it is in the Part.java file
for (int i = 0; i < size; i++) {
Part p = new Part();
p.setDesc(in.readString());
p.setItemNmbr(in.readString());
p.setPrice(new BigDecimal(in.readString()));
this.add(p);
}
}
@Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
@Over开发者_运维知识库ride
public void writeToParcel(Parcel arg0, int arg1) {
int size = this.size();
arg0.writeInt(size);
for (int i = 0; i < size; i++) {
Part p = this.get(i);
arg0.writeString(p.getDesc());
arg0.writeString(p.getItemNmbr());
arg0.writeString(p.getPrice().toString());
}
}
}
And here is the part Object:
public class Part implements Parcelable{
private String desc;
private String itemNmbr;
private BigDecimal price;
public Part(){
}
public Part(String i, String d, BigDecimal p){
this.desc = d;
this.itemNmbr = i;
this.price = p;
}
It also has getters/setters of course.
This is where the list is created:
for (String i : tempList){
Matcher matcher = pattern.matcher(i);
while (matcher.find()){
// getting matches
String desc = matcher.group(6);
String item = matcher.group(9);
BigDecimal price = new BigDecimal(matcher.group(12).toString());
// adding the new part to the parts list
parts.add(new Part(item, desc, price));
}
}
Now, here is where it is received:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// get extras (list)
Bundle b = getIntent().getExtras();
parts = b.getParcelable("parts");
// Part[] PARTS = (Part[]) parts.toArray();
final Part[] PARTS = new Part[] {
new Part("desc", "item id", new BigDecimal(0))
};
final String[] COUNTRIES = new String[] {
"Afghanistan", "Albania", "Algeria", "American Samoa", "Andorra"
};
setListAdapter(new ArrayAdapter<Part>(this, R.layout.list_item, PARTS));
ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
Toast.LENGTH_SHORT).show();
}
});
}
If I don't use the parcel, and just use the array - it works fine. I commented out my test list and it worked fine, otherwise it crashed.
// parts.add(new Part("desc", "item id", new BigDecimal(0)));
// parts.add(new Part("desc2", "item id2", new BigDecimal(1)));
// parts.add(new Part("desc3", "item id3", new BigDecimal(2)));
// create a new bundle
Bundle b = new Bundle();
// put the list into a parcel
b.putParcelable("parts", parts);
Intent i = new Intent(SearchActivity.this, Results.class);
// put the bundle into the intent
i.putExtras(b);
startActivity(i);
Did I do something wrong with the implementation of the Parcel? I can't figure this out. If anyone could help me ASAP - that would be amazing.
In your implementation of Parcelable.Creator, this looks sketchy:
public Object[] newArray(int arg0) {
return null;
}
I believe it should be:
public Object[] newArray(int arg0) {
return new PartsList[arg0];
}
You also need to define your CREATOR object for Part if you're going to declare it to implement Parcelable (although I'm not sure why it needs to).
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