Hi,
1. Use the following expression to hide the control when all check boxes are false. Go to the conditional formatting of the text box and in the first drop down select ‘TheExpression’ in the side box paste the following expression.
my:field1 = string(false()) and my:field2 = string(false()) and my:field3 = string(false()) and my:field4 = string(false()) and …
here field1,field2, field3,.. are check boxes.
2. Use the following expression to hide the text box if atleast one of the check boxes is true.
my:field1 = string(true()) or my:field2 = string(true()) or my:field3 = string(true()) or my:field4 = string(true()) or …
here field1,field2, field3,.. are check boxes.