I don't understand android.content.res.Resources$NotFoundException error in my log
<p>This is the logcat on android studio and what does it mean? If you need more informations please tell me.</p>

<pre><code>4940-4940/werp.moodle E/AndroidRuntime: FATAL EXCEPTION: main
                                                           Process: werp.moodle, PID: 4940
                                                           java.lang.RuntimeException: Unable to start activity ComponentInfo{werp.moodle/werp.moodle.LLandActivity}: android.content.res.Resources$NotFoundException: Resource ID #0x7f040039
                                                               at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3254)
                                                               at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3350)
                                                               at android.app.ActivityThread.access$1100(ActivityThread.java:222)
                                                               at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1795)
                                                               at android.os.Handler.dispatchMessage(Handler.java:102)
                                                               at android.os.Looper.loop(Looper.java:158)
                                                               at android.app.ActivityThread.main(ActivityThread.java:7229)
                                                               at java.lang.reflect.Method.invoke(Native Method)
                                                               at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
                                                            Caused by: android.content.res.Resources$NotFoundException: Resource ID #0x7f040039
                                                               at android.content.res.Resources.getValue(Resources.java:2558)
                                                               at android.content.res.Resources.loadXmlResourceParser(Resources.java:4364)
                                                               at android.content.res.Resources.getLayout(Resources.java:2372)
                                                               at android.view.LayoutInflater.inflate(LayoutInflater.java:427)
                                                               at android.view.LayoutInflater.inflate(LayoutInflater.java:380)
                                                               at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:474)
                                                               at android.app.Activity.setContentView(Activity.java:2387)
                                                               at werp.moodle.LLandActivity.onCreate(LLandActivity.java:52)
                                                               at android.app.Activity.performCreate(Activity.java:6876)
                                                               at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1135)
                                                               at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3207)
                                                               at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3350) 
                                                               at android.app.ActivityThread.access$1100(ActivityThread.java:222) 
                                                               at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1795) 
                                                               at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                               at android.os.Looper.loop(Looper.java:158) 
                                                               at android.app.ActivityThread.main(ActivityThread.java:7229) 
                                                               at java.lang.reflect.Method.invoke(Native Method) 
                                                               at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
</code></pre>