Why does setImageResource crash the app?

Question

Android

Hello everyone, I ran into such a problem, I can’t understand why setImageResource crashes the application, I do this

ImageView simpleImageView = (ImageView) findViewById(R.id.ColMemberID);
simpleImageView.setImageResource(R.mipmap.ic_launcher);

And in the console like this

W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: ovorobyov.radiomaterial, PID: 5141
                  java.lang.RuntimeException: Unable to start activity ComponentInfo{ovorobyov.radiomaterial/ovorobyov.radiomaterial.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2348)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2410)
                      at android.app.ActivityThread.access$800(ActivityThread.java:151)
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1313)
                      at android.os.Handler.dispatchMessage(Handler.java:102)
                      at android.os.Looper.loop(Looper.java:135)
                      at android.app.ActivityThread.main(ActivityThread.java:5345)
                      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:947)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:742)
                   Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference
                      at ovorobyov.radiomaterial.MainActivity.onCreate(MainActivity.java:80)
                      at android.app.Activity.performCreate(Activity.java:6012)
                      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2292)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2410) 
                      at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1313) 
                      at android.os.Handler.dispatchMessage(Handler.java:102) 
                      at android.os.Looper.loop(Looper.java:135) 
                      at android.app.ActivityThread.main(ActivityThread.java:5345) 
                      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:947) 
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:742) 
I/Process: Sending signal. PID: 5141 SIG: 9
Application terminated.

Answer 1

Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference

Something was messed up with findViewById, apparently there is no such id in this Activity, or it is not an ImageView, it's not about setImageResource, the same will happen with any other methods of this ImageView.