Question

我有关于parcelable class（android）的问题。

到目前为止，我已经在2 Intent之间传递了一个DoubleArray而没有任何问题：

new double[] latLong = new double[]{loc.getLatitude(),loc.getLongitude()};
...
intent.putExtra(Site.LATTITUDE, latLong);   
...
startActivityForResult(intent, this.ACCESS_GOOGLE);

今天，我尝试使用parcelable类为相同的活动添加新数据。我的可分类：

package common;

import android.os.Parcel;
import android.os.Parcelable;

public class Site implements Parcelable {

    private int id;
    private String site_name;
    private int category ;
    private double latitude;
    private double longitude;

    /**
     * 
     * @param id
     * @param site_name
     * @param category
     */
    public Site(int id, String site_name, int category,double latitude, double lonngitude){
        this.id=id;
        this.site_name=site_name;
        this.category=category;
        this.latitude=latitude;
        this.longitude=longitude;

    }

    public Site(Parcel in){
        readFromParcel(in);
    }

    @Override
    public int describeContents() {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(this.id);
        dest.writeString(this.site_name);
        dest.writeInt(this.category);
        dest.writeDouble(this.latitude);
        dest.writeDouble(this.longitude);
    }


    /**
     * 
     * @param in
     */
    private void readFromParcel(Parcel in) {        
        this.id     = in.readInt();
        this.site_name  = in.readString();
        this.category   = in.readInt();
        this.latitude   = in.readInt();
        this.longitude  = in.readInt();
    }


   public static final Parcelable.Creator CREATOR =
        new Parcelable.Creator() {

            public SiteGoogle createFromParcel(Parcel in) {
                return new Site(in);
            }

            public SiteGoogle[] newArray(int size) {
                return new Site[size];
            }
        };


    /* GETTER / SETTER */

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getSite_name() {
        return site_name;
    }

    public void setSite_name(String site_name) {
        this.site_name = site_name;
    }

    public int getCategory() {
        return category;
    }

    public void setCategory(int category) {
        this.category = category;
    }

    public double getLatitude() {
        return latitude;
    }

    public void setLatitude(double latitude) {
        this.latitude = latitude;
    }

    public double getLongitude() {
        return longitude;
    }

    public void setLongitude(double longitude) {
        this.longitude = longitude;
    }

}

我在java ArrayList中放置了一些Site对象（上面的类），并使用以下代码将此列表传递给我的第二个Activity：

ArrayList<Site> sitesForMap = new ArrayList<Site>();

for(int i=0; i<sites.size();i++){

    SiteGoogle site = new SiteGoogle(
            sites.get(i).getId(),
            sites.get(i).getSite_name(),
            sites.get(i).getCat(),
            sites.get(i).getLatitude(),
            sites.get(i).getLongitude());

    sitesForGoogle.add(site); 
}

//put data in the intent
intent.putExtra(Site.LATTITUDE, latLong); //first data that worked well until now
intent.putParcelableArrayListExtra(Site.JSON_ARRAY, sitesForMap);   //my new data
startActivityForResult(intent, this.ACCESS_GOOGLE);

此代码执行完美（sitesForMap和latLong不为null）但在第二个Activity中，当我尝试实例化第一个Double []参数时，发生错误。

Bundle bundle = getIntent().getExtras();
double[] adresse = (double[]) bundle.getDoubleArray(Site.LATTITUDE);    //worked well until today
List<Site> sitesList = bundle.getParcelableArrayList(Site.JSON_ARRAY);

错误：

11-04 03:00:47.248: D/AndroidRuntime(642): Shutting down VM
11-04 03:00:47.248: W/dalvikvm(642): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
11-04 03:00:47.350: E/AndroidRuntime(642): FATAL EXCEPTION: main
11-04 03:00:47.350: E/AndroidRuntime(642): java.lang.OutOfMemoryError
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readArray(Parcel.java:1476)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readValue(Parcel.java:1810)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readListInternal(Parcel.java:2017)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readArrayList(Parcel.java:1461)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readValue(Parcel.java:1792)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Parcel.readMapInternal(Parcel.java:2008)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Bundle.unparcel(Bundle.java:208)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Bundle.getDoubleArray(Bundle.java:1431)
11-04 03:00:47.350: E/AndroidRuntime(642):  at alij.ne.jp.GoogleMapActivity.onCreate(GoogleMapActivity.java:111)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Handler.dispatchMessage(Handler.java:99)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.os.Looper.loop(Looper.java:123)
11-04 03:00:47.350: E/AndroidRuntime(642):  at android.app.ActivityThread.main(ActivityThread.java:4627)
11-04 03:00:47.350: E/AndroidRuntime(642):  at java.lang.reflect.Method.invokeNative(Native Method)
11-04 03:00:47.350: E/AndroidRuntime(642):  at java.lang.reflect.Method.invoke(Method.java:521)
11-04 03:00:47.350: E/AndroidRuntime(642):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-04 03:00:47.350: E/AndroidRuntime(642):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-04 03:00:47.350: E/AndroidRuntime(642):  at dalvik.system.NativeStart.main(Native Method)
11-04 03:03:10.460: I/Process(642): Sending signal. PID: 642 SIG: 9
11-04 03:03:11.099: D/dalvikvm(652): GC_EXTERNAL_ALLOC freed 792 objects / 61464 bytes in 48ms

有人知道这是什么问题吗？

感谢您阅读我的留言！

Answer 1

您的readFromParcel和writeToParcel方法不匹配。

@Override
public void writeToParcel(Parcel dest, int flags) {
    dest.writeInt(this.id);
    dest.writeString(this.site_name);
    dest.writeInt(this.category);
    dest.writeDouble(this.latitude);
    dest.writeDouble(this.longitude);
}

private void readFromParcel(Parcel in) {        
    this.id     = in.readInt();
    this.site_name  = in.readString();
    this.category   = in.readInt();
    this.latitude   = in.readInt(); // <-------- this
    this.longitude  = in.readInt(); // <-------- and this
}

double使用8个字节，int在parcel上使用4个字节。一个parcel不包含类型信息（除非你使用writeValue和readValue），所以如果你读取和写入方法不匹配，将会读取一个意外的值，它会弄乱整个包裹。

如果你真的想要一个int，请使用（int）in.readDouble（）而不是in.readInt（）。

Android：getParcelableArrayList错误（内存不足）

1 个答案: