getFreeRowForColumn method
Implementation
int getFreeRowForColumn(int x) {
if (this.height() == 0) {
return 0;
}
final entries = this.s.asMap().entries.toList();
final idx = entries.indexWhere((data) {
var row = data.value;
return row.length == 0 || x >= row.length || row[x] == null;
});
var y = idx == -1 ? this.height() : entries[idx].key;
return y;
}