android页面转换laybrary集成空指针异常

Posted 2023-02-26

【中文标题】android页面转换laybrary集成空指针异常

【英文标题】：android page transition laybrary integration null pointer exception

【发布时间】：2016-11-19 11:13:53

【问题描述】：

大家好，我在尝试集成 android-page-transition 后遇到此错误 nullPointerException 错误，但找不到原因 这是显示错误的代码 PS：它与库中的完全相同的 cude 我刚刚将代码集成到 mywork 中

/**
 * Réglage Menu immersive title
 */
private void dealStatusBar() 
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) 
        int statusBarHeight = getStatusBarHeight();
        ViewGroup.LayoutParams lp = positionView.getLayoutParams();
        lp.height = statusBarHeight;
        positionView.setLayoutParams(lp);
    

这是我运行时遇到的错误

11-19 12:11:30.781 16089-16089/mobile.esprit.tn.mobileteam E/AndroidRuntime: FATAL EXCEPTION: main
Process: mobile.esprit.tn.mobileteam, PID: 16089
java.lang.RuntimeException: Unable to start activity ComponentInfomobile.esprit.tn.mobileteam/mobile.esprit.tn.mobileteam.Activities.Project.PrjectsCardViews: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.ViewGroup$LayoutParams android.view.View.getLayoutParams()' on a null object reference
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2693)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2758)
    at android.app.ActivityThread.access$900(ActivityThread.java:177)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:145)
    at android.app.ActivityThread.main(ActivityThread.java:5942)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195)
 Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.ViewGroup$LayoutParams android.view.View.getLayoutParams()' on a null object reference
    at mobile.esprit.tn.mobileteam.Activities.Project.PrjectsCardViews.dealStatusBar(PrjectsCardViews.java:129)
    at mobile.esprit.tn.mobileteam.Activities.Project.PrjectsCardViews.onCreate(PrjectsCardViews.java:54)
    at android.app.Activity.performCreate(Activity.java:6289)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2758) 
    at android.app.ActivityThread.access$900(ActivityThread.java:177) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:145) 
    at android.app.ActivityThread.main(ActivityThread.java:5942) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at java.lang.reflect.Method.invoke(Method.java:372) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195) 

PrjectsCardViews.java:129 是我在上面发布的代码

【参考方案1】：

好的，我发现问题是由复制和粘贴引起的转储错误，我没有将 oncreate 引用到必要的活动布局

【参考方案2】：

您可能已经复制了项目，但您可能忘记更改<com.stone.transition.DragLayout android:id="@+id/drag_layout" 当您在项目中合并代码时检查它是否可以工作