Error when clicking on listview Android (Java)

Question

I get an error whenever I click on an item in a listview from the 8th, the previous ones work perfectly

Details: when clicking on the list, I call the method with the number of the item clicked, with that number instantiating a RelativeLayout with the child of the listview with the item number, then, with the layout, instantiating a TextView and a CheckBox *Sorry for bad English

listview code:

@Override
public void onItemClick(AdapterView<?> p1, View p2, int p3, long p4)
{
    removerDaLista(p3);
} });

method code:

public void removerDaLista(int index){
    paraTachar.add(Integer.valueOf(index));
    RelativeLayout rl = (RelativeLayout)listView.getChildAt(index);
    TextView txt = (TextView) rl.findViewById(R.id.text);
    CheckBox cb = (CheckBox) rl.findViewById(R.id.cb);
        
    desativarLista(txt,cb);
}

Error:

FATAL EXCEPTION: main
Process: com.mycompany.myapp, PID: 611
java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference
    at com.mycompany.myapp.MainActivity.removerDaLista(MainActivity.java:88)
    at com.mycompany.myapp.MainActivity$100000001.onItemClick(MainActivity.java:71)
    at android.widget.AdapterView.performItemClick(AdapterView.java:310)
    at android.widget.AbsListView.performItemClick(AbsListView.java:1164)
    at android.widget.AbsListView$PerformClick.run(AbsListView.java:3132)
    at android.widget.AbsListView.onTouchUp(AbsListView.java:4059)
    at android.widget.AbsListView.onTouchEvent(AbsListView.java:3818)
    at android.view.View.dispatchTouchEvent(View.java:10023)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2626)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2307)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2632)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2321)
    at com.android.internal.policy.DecorView.superDispatchTouchEvent(DecorView.java:416)
    at com.android.internal.policy.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1808)
    at android.app.Activity.dispatchTouchEvent(Activity.java:3124)
    at com.android.internal.policy.DecorView.dispatchTouchEvent(DecorView.java:378)
    at android.view.View.dispatchPointerEvent(View.java:10243)
    at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:4438)
    at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:4306)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
    at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3999)
    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
    at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4056)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
    at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:6247)
    at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:6221)
    at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:6182)
    at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:6350)
    at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
    at android.os.MessageQueue.nativePollOnce(Native Method)
    at android.os.MessageQueue.next(MessageQueue.java:323)
    at android.os.Looper.loop(Looper.java:136)
    at android.app.ActivityThread.main(ActivityThread.java:6152)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:890)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:780)

question from:https://stackoverflow.com/questions/65862756/error-when-clicking-on-listview-android-java

Answer 1

The reason for this is most probably the view could not be found. In your case it's the view R.id.text or R.id.cb or maybe both. Make sure those TextView and CheckBox exist in the layout or make sure you used their correct id.

EDIT: It may also be an index problem, the view at that index could not be found. In your code:

rl = (RelativeLayout)listView.getChildAt(index);

Replace it with:

 rl = (RelativeLayout)listView.getChildAt(index-1);

Maybe the index is starting from 1 instead of 0.