question: public void specifyLines ( int line_num ) { int childNum = 0 ; if ( line_num > lineNumList . size ( ) ) { line_num = lineNumList . size ( ) ; } for ( int i = 0 ; i < line_num ; i ++ ) { childNum += lineNumList . get ( i ) ; } List < View > viewList = new ArrayList < > ( ) ; for ( int i = 0 ; i < childNum ; i ++ ) { viewList . add ( getChildAt ( i ) ) ; } removeAllViews ( ) ; for ( View v : viewList ) { addView ( v ) ; } }
target:  cut the flowlayout to the specified num of lines