Difficulty with unmarshalling in parcelable

问题

Here is my code of writing to a parcel

public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(poiDescription);
        dest.writeString(latitude);
        dest.writeString(longitude);
        dest.writeString(placeName);
        dest.writeString(plistPath);
        dest.writeString(poiDirName);
            if (null != isMascotPresent)
                dest.writeString(isMascotPresent);
            if (null != startMascottTime)
                dest.writeInt(startMascottTime);
            if (null != mascottDuration)
                dest.writeInt(mascottDuration);
}

public PointOfInterest(Parcel source) { 
        poiDescription = source.readString();
        latitude = source.readString();
        longitude = source.readString();
        placeName = source.readString();
        plistPath = source.readString();
        poiDirName = source.readString();
        audioLinkDownload = source.readString();
        audioLinkStream = source.readString();
        poiName = source.readString();
        poiIndex = source.readInt();
        poiPaused = source.readString();
        source.readList(imageList, null);
        source.readList(durationList, null);
        if (null != isMascotPresent)
            isMascotPresent = source.readString();
        if (null != startMascottTime)
               startMascottTime=source.readInt();
        if (null != mascottDuration)
                  mascottDuration=source.readInt();
}


This is how I am reading the values
listOfPOI = getIntent().getParcelableArrayListExtra("poi");

This codw works fine without the mascot above.

But when I add those 3 lines about mascot, my application is crashing. I am breaking my head onthis, I am not getting why is this happening, can anyone please let me know the issue?

I am getting the run time exception and problem saying there is unmarshalling error for the parcelable

This is the exception I am getting

 ERROR/AndroidRuntime(2061): FATAL EXCEPTION: main
 ERROR/AndroidRuntime(2061): java.lang.RuntimeException: Unable to start activity       ComponentInfo{com.Invenger/com.Invenger.Player.Audio}: java.lang.RuntimeException: Parcel android.os.Parcel@40570848: Unmarshalling unknown type code 7536748 at offset 1064
 ERROR/AndroidRuntime(2061):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
 ERROR/AndroidRuntime(2061):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
 ERROR/AndroidRuntime(2061):     at android.app.ActivityThread.access$1500(ActivityThread.java:117)
 ERROR/AndroidRuntime(2061):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
 ERROR/AndroidRuntime(2061):     at android.os.Handler.dispatchMessage(Handler.java:99)
 ERROR/AndroidRuntime(2061):     at android.os.Looper.loop(Looper.java:130)
 ERROR/AndroidRuntime(2061):     at android.app.ActivityThread.main(ActivityThread.java:3683)
 ERROR/AndroidRuntime(2061):     at java.lang.reflect.Method.invokeNative(Native Method)
 ERROR/AndroidRuntime(2061):     at java.lang.reflect.Method.invoke(Method.java:507)
 ERROR/AndroidRuntime(2061):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
ERROR/AndroidRuntime(2061):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
 ERROR/AndroidRuntime(2061):     at dalvik.system.NativeStart.main(Native Method)
 ERROR/AndroidRuntime(2061): Caused by: java.lang.RuntimeException: Parcel android.os.Parcel@40570848: Unmarshalling unknown type code 7536748 at offset 1064
 ERROR/AndroidRuntime(2061):     at android.os.Parcel.readValue(Parcel.java:1913)
 ERROR/AndroidRuntime(2061):     at android.os.Parcel.readListInternal(Parcel.java:2092)
 ERROR/AndroidRuntime(2061):     at android.os.Parcel.readArrayList(Parcel.java:1536)
 ERROR/AndroidRuntime(2061):     at android.os.Parcel.readValue(Parcel.java:1867)
ERROR/AndroidRuntime(2061):     at android.os.Parcel.readMapInternal(Parcel.java:2083)
ERROR/AndroidRuntime(2061):     at android.os.Bundle.unparcel(Bundle.java:208)
ERROR/AndroidRuntime(2061):     at   android.os.Bundle.getParcelableArrayList(Bundle.java:1144)
 ERROR/AndroidRuntime(2061):     at android.content.Intent.getParcelableArrayListExtra(Intent.java:3448)
    ERROR/AndroidRuntime(2061):     at com.Invenger.Player.Audio.onCreate(Audio.java:162)
    ERROR/AndroidRuntime(2061):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
   ERROR/AndroidRuntime(2061):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
   ERROR/AndroidRuntime(2061):     ... 11 more

回答1:

Unless you're initializing isMascotPresent, startMascottTime and mascottDuration somewhere they're always going to be null in the constructor, PointOfInterest(Parcel source). So even if you wrote values when parceling the object they wouldn't be read and the following values would be incorrect.

Instead of checking if they're null when reading/writing the mascot info you could use a boolean:

    if (null != isMascotPresent) {
        dest.writeByte((byte) 1);
        dest.writeString(isMascotPresent);
        dest.writeInt(startMascottTime);
        dest.writeInt(mascottDuration);
    } else {
        dest.writeByte((byte) 0);
    }

And to read it back in:

    if(source.readByte() == 1) {
        isMascotPresent = source.readString();
        startMascottTime = source.readInt();
        mascottDuration = source.readInt();
    } else {
        isMascotPresent = null;
        startMascottTime = null;
        mascottDuration = null;
    }

And you're also reading more values in than you're writing out to the parcel. Values need to be written and read in the same order.

回答2:

You can use android studio plugin, which generates Android Parcelable boilerplate code for you. File->Settings->Plugins->Browse Repositories->search for Android Parcelable code generator. OR https://plugins.jetbrains.com/plugin/7332?pr=

Problem is in sequence of writing and reading of object...sequence should be same, as it is like reading file.

回答3:

I fixed the problem somehow. I made it as static instead of making it parcelable.Ihis may not be the standard way, of making it static. But I feel that there is a limit on the size of parcel. If I add some 15 or more variable it is not working. So it is working for me now.

Any better answer will be accepted

来源：https://stackoverflow.com/questions/7452584/difficulty-with-unmarshalling-in-parcelable

标签

android

unmarshalling

parcelable

runtimeexception