Getting an item from an empty table widget

[ProTonS]

Hi, everybody, its my first time here.

I have a little problem, I am a beginner in qt, but I liking it. Well, to the problem:

QTableWidgetItem *item1;
QString helper;
item1 = ui.mywidget_table->item(0,1);
helper = item1->text();

QTableWidgetItem *item1;
QString helper;
item1 = ui.mywidget_table->item(0,1);
helper = item1->text();

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I´ve received a error in the last line because my cell is empty, but I think that I need to test if the cell is empty, how can I make that?

Thx in advance.

Jorge.