小编Oya*_*Oya的帖子

我是Kotlin的新手，正在尝试制作对象列表的副本。我遇到的问题是，当我更改新副本中的项目时，旧列表也会被更改。这是对象：

class ClassA(var title: String?, var list: ArrayList<ClassB>, var selected: Boolean)
class ClassB(val id: Int, val name: String) 

我尝试这样做，但是不起作用：

val oldList:ArrayList<ClassA>


val newList :ArrayList<ClassA> = ArrayList()
newList.addAll(oldList)

当我尝试更新应用程序中的内容时,我的App Widget出现问题.我的小部件包含列表视图.

listview工作正常,每隔30分钟更新一次,但是当我在应用程序中进行更改时,我还需要更新它.这是我的代码:

public class WidgetListProvider extends AppWidgetProvider {

    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        final int N = appWidgetIds.length;
        ComponentName component;
        for (int i = 0; i < N; ++i) {
            RemoteViews remoteViews = updateWidgetListView(context,
                    appWidgetIds[i]);
            appWidgetManager.updateAppWidget(appWidgetIds[i], remoteViews);

            component=new ComponentName(context,WidgetListProvider.class);
            appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds, R.id.listViewWidget);
            appWidgetManager.updateAppWidget(component, remoteViews);
        }

        super.onUpdate(context, appWidgetManager, appWidgetIds);
    }

    private RemoteViews updateWidgetListView(Context context, int appWidgetId) {
        RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget_list_layout);

        Intent svcIntent = new Intent(context, WidgetService.class);
        svcIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
        svcIntent.setData(Uri.parse(svcIntent.toUri(Intent.URI_INTENT_SCHEME)));
        remoteViews.setRemoteAdapter(R.id.listViewWidget, svcIntent);
        remoteViews.setEmptyView(R.id.listViewWidget, R.id.empty_view); …