Question

I had a simple table and it add theTableRow and delete the TableRow dynamically. my requirement says to keep the first row of the table as it is heading so i need to use the removeView(star,end); method but it seems to b not working and throws the NullPointerException. i also used the removeAllViews() method, it working correctly so i cant understand why it throws the NullPointerException! how can i solve my problem?
this is my code:–

       TableLayout table = (TableLayout) findViewById(R.id.myTable);
        table.removeViews(1, table.getChildCount());
        //table.removeAllViews();
        table.postInvalidate();
        bindData();

and this is the logcat errors :–

10-22 06:16:05.204: E/AndroidRuntime(828): Uncaught handler: thread main exiting due to uncaught exception
10-22 06:16:05.214: E/AndroidRuntime(828): java.lang.NullPointerException
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.view.ViewGroup.removeViewsInternal(ViewGroup.java:2116)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.view.ViewGroup.removeViews(ViewGroup.java:2064)
10-22 06:16:05.214: E/AndroidRuntime(828):  at com.techdeedapps.diamond.ViewStockActivity$BackgroungLoadingDiamondList.onPostExecute(ViewStockActivity.java:348)
10-22 06:16:05.214: E/AndroidRuntime(828):  at com.techdeedapps.diamond.ViewStockActivity$BackgroungLoadingDiamondList.onPostExecute(ViewStockActivity.java:1)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.os.AsyncTask.finish(AsyncTask.java:417)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.os.AsyncTask.access$300(AsyncTask.java:127)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.os.Handler.dispatchMessage(Handler.java:99)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.os.Looper.loop(Looper.java:123)
10-22 06:16:05.214: E/AndroidRuntime(828):  at android.app.ActivityThread.main(ActivityThread.java:4363)
10-22 06:16:05.214: E/AndroidRuntime(828):  at java.lang.reflect.Method.invokeNative(Native Method)
10-22 06:16:05.214: E/AndroidRuntime(828):  at java.lang.reflect.Method.invoke(Method.java:521)
10-22 06:16:05.214: E/AndroidRuntime(828):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
10-22 06:16:05.214: E/AndroidRuntime(828):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
10-22 06:16:05.214: E/AndroidRuntime(828):  at dalvik.system.NativeStart.main(Native Method)

it works perfectly on removing all view by using this method table.removeAllView() .then why it is not working on using this method table.removeViews(1,table.getChildCount() ?

Answer 1

Since you want to remove all items but the first one you need to make sure to only remove “number of child elements minus the last one”. I.e.

table.removeViews(1, table.getChildCount() - 1);

With the code line in your question you will try to remove one child view more than you actually have in your TableLayout.