Controll flutter pageview widgets or variables for one page only - flutter

Question

How to control specific widget to hide or to show in pageview. In PageView Widget in flutter for specific page only, how we can control over widget to be hidden or shown based on bool value. how we can utilize pageview controller to do this

Answer 1

you can change the children in the widget tree depending on a boolean value.
Example: child: condition ? WidgetWhenTrue : WidgetWhenFalse
UPDATE
The best way I found is, that you create your pages and page children dynamicly.
You could provide a List<Widget> which will represent the max. Content and then remove the widget you don't want to have.
Or you could add the widgets on the fly to the pages.
import 'package:flutter/material.dart';
class PageViewWidget extends StatefulWidget {
#override
_PageViewWidgetState createState() => _PageViewWidgetState();
}
class _PageViewWidgetState extends State<PageViewWidget> {
PageController _pageController;
#override
void dispose() {
_pageController.dispose();
super.dispose();
}
List<Text> maxContent = [
Text('text 1'),
Text('text 2'),
Text('text 3'),
Text('text 4'),
Text('text 5'),
Text('text 6')
];
bool condition = true;
Container dynamicPageChildren({Color color, List<int> delPos}) {
Container newPage;
List<Widget> newContent = List.from(maxContent);
// modify your Widget List
print('length = ${maxContent.length} ');
for (int i in delPos.reversed) {
// use reversed or provide the last elemt to remove first if not,
// your list will shrink and the element you want to remove last does not exist or is the wrong one
print('delete at pos $i');
newContent.removeAt(i);
}
// add it to the page
newPage = Container(
color: color,
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: newContent));
return newPage;
}
List<Container> dynamicPages({List<Color> colorList}) {
// you could also pass the index positions into this function
// or call your logic to decide which index should not be displayed
List<Container> newPageList = [];
// modify your Widget List
int i = 0;
for (Color color in colorList) {
// example with given indices
// newPageList.add(dynamicPageChildren(color: color, delPos: [1, 3, 5]));
newPageList.add(dynamicPageChildren(color: color, delPos: [i]));
i = i + 1;
}
return newPageList;
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
child: PageView(
controller: _pageController,
children: dynamicPages(
colorList: [Colors.red, Colors.orange, Colors.yellow])),
),
);
}
}