我的Android应用平板电脑已经过优化,我按照教程here进行了操作:
一切都很棒,但我试图用ActionBar
中的按钮选择一个项目(比如第一项)。
我尝试this answer使用performItemClick
,但我收到了java.lang.IllegalStateException
in android.support.v4.app.ListFragment.ensureList
,java.lang.IllegalStateException: Content view not yet created
和java.lang.NullPointerException
in android.content.ComponentName.<init>
我已尝试检查ListView
是否为null
,并仍在Play商店中获取错误报告。如何以编程方式正确选择列表中的项目?
更新以添加logcat,代码几乎与链接中的教程完全相同:
Logcat A:
java.lang.IllegalStateException: Content view not yet created
at android.support.v4.app.ListFragment.ensureList(ListFragment.java:328)
at android.support.v4.app.ListFragment.getListView(ListFragment.java:222)
at com.ccwilcox.meteorshower.MeteorList.showMeteorDetails(MeteorList.java:69)
at com.ccwilcox.meteorshower.MeteorList.onListItemClick(MeteorList.java:62)
at android.support.v4.app.ListFragment$2.onItemClick(ListFragment.java:58)
at android.widget.AdapterView.performItemClick(AdapterView.java:298)
at android.widget.AbsListView.performItemClick(AbsListView.java:1280)
at com.ccwilcox.meteorshower.MainActivity.viewUpcomingEvent(MainActivity.java:648)
at com.ccwilcox.meteorshower.MainActivity.onOptionsItemSelected(MainActivity.java:534)
at android.app.Activity.onMenuItemSelected(Activity.java:2606)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:361)
at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:1045)
at com.android.internal.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:735)
at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:149)
at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:874)
at com.android.internal.view.menu.ActionMenuView.invokeItem(ActionMenuView.java:592)
at com.android.internal.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:149)
at android.view.View.performClick(View.java:4222)
at android.view.View$PerformClick.run(View.java:17273)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4895)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:994)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:761)
at dalvik.system.NativeStart.main(Native Method)
Logcat B:
java.lang.NullPointerException
at android.content.ComponentName.<init>(ComponentName.java:75)
at android.content.Intent.<init>(Intent.java:2874)
at com.ccwilcox.meteorshower.MeteorList.showMeteorDetails(MeteorList.java:86)
at com.ccwilcox.meteorshower.MeteorList.onListItemClick(MeteorList.java:62)
at android.support.v4.app.ListFragment$2.onItemClick(ListFragment.java:58)
at android.widget.AdapterView.performItemClick(AdapterView.java:284)
at android.widget.ListView.performItemClick(ListView.java:3701)
at com.ccwilcox.meteorshower.MainActivity.viewUpcomingEvent(MainActivity.java:648)
at com.ccwilcox.meteorshower.MainActivity.onOptionsItemSelected(MainActivity.java:534)
at android.app.Activity.onMenuItemSelected(Activity.java:2205)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:361)
at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:779)
at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:143)
at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:861)
at com.android.internal.view.menu.IconMenuView.invokeItem(IconMenuView.java:532)
at com.android.internal.view.menu.IconMenuItemView.performClick(IconMenuItemView.java:122)
at android.view.View$PerformClick.run(View.java:9152)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3687)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
at dalvik.system.NativeStart.main(Native Method)
更新2 以下是导致问题的代码:
if (mListFragment.listView != null) {
mListFragment.listView.performItemClick(mListFragment.listView.getAdapter().getView(position, null, null), position, mListFragment.listView.getAdapter().getItemId(position));
}