相关疑难解决方法(0)

我想让我的应用看起来更专业,所以我决定要制作一个闪屏.

我将如何创建它然后实现它？

我在我的项目中添加了一个底部导航活动，但是当我开始相关活动时，它给出了一个空指针异常。

它说异常是在第 28 行触发的

在 lk.apiit.eea.mobile.Activities.CompanyProfile.onCreate(CompanyProfile.java:28)

以下是异常和代码请帮我解决这个问题..谢谢

java.lang.RuntimeException: Unable to start activity ComponentInfo{lk.apiit.eea.mobile/lk.apiit.eea.mobile.Activities.CompanyProfile}: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.appcompat.app.ActionBar.setTitle(java.lang.CharSequence)' on a null object reference
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2720)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2781)
    at android.app.ActivityThread.-wrap12(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1508)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:241)
    at android.app.ActivityThread.main(ActivityThread.java:6274)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
 Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.appcompat.app.ActionBar.setTitle(java.lang.CharSequence)' on a null object reference
    at androidx.navigation.ui.ActionBarOnDestinationChangedListener.setTitle(ActionBarOnDestinationChangedListener.java:48)
    at androidx.navigation.ui.AbstractAppBarOnDestinationChangedListener.onDestinationChanged(AbstractAppBarOnDestinationChangedListener.java:100)
    at androidx.navigation.NavController.addOnDestinationChangedListener(NavController.java:218)
    at androidx.navigation.ui.NavigationUI.setupActionBarWithNavController(NavigationUI.java:220)
    at lk.apiit.eea.mobile.Activities.CompanyProfile.onCreate(CompanyProfile.java:28)
    at android.app.Activity.performCreate(Activity.java:6720)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2673)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2781) …