Question

您好我正在处理一个应用程序，并尝试将对象列表（IntentBinders）从MainActivity传递给RouteSummary类，但应用程序崩溃时出现异常。

public class IntentBinder implements Serializable {
    public String rtName;
    public double rtDistance;
    public int rtfare;
}

MainActivity：

Intent passIntent  = new Intent(getApplicationContext(),RouteSummary.class);
IntentBinder obj1 = new IntentBinder();
                        obj1.rtName = finalRt1Name;
                        obj1.rtDistance = distanceRt1;
                        obj1.rtfare = fareRt1;
                        IntentBinder obj2 = new IntentBinder();
                        obj2.rtName = finalRt2Name;
                        obj2.rtDistance = distanceRt2;
                        obj2.rtfare = fareRt2;
                        ArrayList<IntentBinder> list = new ArrayList<IntentBinder>();
                        list.add(obj1);
                        list.add(obj2);
                        Bundle bundleObj = new Bundle();
                        bundleObj.putSerializable("key", list);
                        passIntent.putExtras(bundleObj);
                        startActivity(passIntent);

RouteSummary.Java（接收活动）

setContentView(R.layout.route_summary);

        try{
            // Get thIne Bundle Object        
            Bundle bundleObject = getIntent().getExtras();

                // Get ArrayList Bundle
            ArrayList<IntentBinder> classObject = (ArrayList<IntentBinder>) bundleObject.getSerializable("key");


            for(int index = 0; index < classObject.size(); index++){

                IntentBinder Object = classObject.get(index);
                Toast.makeText(getApplicationContext(), "Id is :"+Object.rtName, Toast.LENGTH_SHORT).show();
            }
        } catch(Exception e){
            e.printStackTrace();
        }

LogCat：

05-27 14:36:50.697: E/AndroidRuntime(31484): FATAL EXCEPTION: main
05-27 14:36:50.697: E/AndroidRuntime(31484): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.webmonopolists.project_linx/com.webmonopolists.project_linx.RouteSummary}: java.lang.NullPointerException
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1734)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1753)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread.access$1500(ActivityThread.java:155)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:999)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.os.Handler.dispatchMessage(Handler.java:130)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.os.Looper.loop(SourceFile:351)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread.main(ActivityThread.java:3820)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at java.lang.reflect.Method.invokeNative(Native Method)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at java.lang.reflect.Method.invoke(Method.java:538)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:969)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:727)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at dalvik.system.NativeStart.main(Native Method)
05-27 14:36:50.697: E/AndroidRuntime(31484): Caused by: java.lang.NullPointerException
05-27 14:36:50.697: E/AndroidRuntime(31484):    at com.webmonopolists.project_linx.RouteSummary.onCreate(RouteSummary.java:42)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1082)
05-27 14:36:50.697: E/AndroidRuntime(31484):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1698)
05-27 14:36:50.697: E/AndroidRuntime(31484):    ... 11 more

Answer 1

改为使用public class IntentBinder implements Serializable工具Parcelable。

要ArrayList使用IntentBinder：

i.putParcelableArrayListExtra(name, value)

获取使用：

getIntent().getParcelableArrayListExtra(name)

通过意图传递对象的Arraylist

1 个答案: