Flutter 如何将自定义偏移设置为";浮动操作按钮定位“;在断头台上,在颤栗?
所以最近引入了FloatingActionButtonLocation,它有四个值,所有值都用于底部对齐。我希望它在顶部,在应用程序栏的一半以下。但我不知道如何设置自定义偏移量。这方面的官方文档也很少。这违反了材料设计指南。但您可以通过将原始源代码中的Flutter 如何将自定义偏移设置为";浮动操作按钮定位“;在断头台上,在颤栗?,flutter,Flutter,所以最近引入了FloatingActionButtonLocation,它有四个值,所有值都用于底部对齐。我希望它在顶部,在应用程序栏的一半以下。但我不知道如何设置自定义偏移量。这方面的官方文档也很少。这违反了材料设计指南。但您可以通过将原始源代码中的scaffoldGeometry.contentBottom更改为scaffoldGeometry.contentTop来实现。下面的代码应该可以工作 import 'package:flutter/material.dart'; import '
scaffoldGeometry.contentBottom
更改为scaffoldGeometry.contentTop
来实现。下面的代码应该可以工作
import 'package:flutter/material.dart';
import 'dart:math' as math;
class HomeHeader extends StatefulWidget {
final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
@override
HomeHeaderState createState() {
return new HomeHeaderState();
}
}
class HomeHeaderState extends State<HomeHeader> {
static const FloatingActionButtonLocation centerDocked = _CenterDockedFloatingActionButtonLocation();
@override
Widget build(BuildContext context) {
return new Scaffold(
key: widget._scaffoldKey,
appBar: AppBar(
title: Text('duh'),
),
floatingActionButtonLocation:centerDocked,
floatingActionButton: FloatingActionButton(
child: const Icon(Icons.add), onPressed: () {
},),
body: new Container()
);
}
}
class _CenterDockedFloatingActionButtonLocation extends _DockedFloatingActionButtonLocation {
const _CenterDockedFloatingActionButtonLocation();
@override
Offset getOffset(ScaffoldPrelayoutGeometry scaffoldGeometry) {
final double fabX = (scaffoldGeometry.scaffoldSize.width - scaffoldGeometry.floatingActionButtonSize.width) / 2.0;
return Offset(fabX, getDockedY(scaffoldGeometry));
}
}
abstract class _DockedFloatingActionButtonLocation extends FloatingActionButtonLocation {
const _DockedFloatingActionButtonLocation();
@protected
double getDockedY(ScaffoldPrelayoutGeometry scaffoldGeometry) {
final double contentBottom = scaffoldGeometry.contentTop;
final double appBarHeight = scaffoldGeometry.bottomSheetSize.height;
final double fabHeight = scaffoldGeometry.floatingActionButtonSize.height;
final double snackBarHeight = scaffoldGeometry.snackBarSize.height;
double fabY = contentBottom - fabHeight / 2.0;
if (snackBarHeight > 0.0)
fabY = math.min(fabY, contentBottom - snackBarHeight - fabHeight - kFloatingActionButtonMargin);
if (appBarHeight > 0.0)
fabY = math.min(fabY, contentBottom - appBarHeight - fabHeight / 2.0);
final double maxFabY = scaffoldGeometry.scaffoldSize.height - fabHeight;
return math.min(maxFabY, fabY);
}
}
导入“包装:颤振/材料.省道”;
导入'dart:math'作为数学;
类HomeHeader扩展了StatefulWidget{
最终GlobalKey _scaffoldKey=新的GlobalKey();
@凌驾
HomeHeaderState createState(){
返回新的HomeHeaderState();
}
}
类HomeHeaderState扩展状态{
静态常量FloatingActionButtonLocation centerDocked=\u CenterDockedFloatingActionButtonLocation();
@凌驾
小部件构建(构建上下文){
归还新脚手架(
钥匙:小部件。_scaffoldKey,
appBar:appBar(
标题:文本(“duh”),
),
浮动操作按钮位置:中心停靠,
浮动操作按钮:浮动操作按钮(
子:常量图标(Icons.add),按下时:(){
},),
正文:新容器()
);
}
}
类_CenterDockedFloatingActionButtonLocation扩展了_DockedFloatingActionButtonLocation{
const_CenterDockedFloatingActionButtonLocation();
@凌驾
偏移量getOffset(脚手架LDPrelayoutGeometry脚手架几何){
最终双fabX=(scaffoldGeometry.scaffoldSize.width-scaffoldGeometry.floatingActionButtonSize.width)/2.0;
返回偏移量(fabX,getDockedY(脚手架几何));
}
}
抽象类DockedFloatingActionButtonLocation扩展了FloatingActionButtonLocation{
const_dockdfloatingActionButtonLocation();
@保护
double getDockedY(ScaffoldPrelayoutGeometry scaffoldGeometry){
最终双contentBottom=scaffoldGeometry.contentTop;
最终双appBarHeight=脚手架几何体.bottomSheetSize.height;
最终双fabHeight=脚手架几何体.floatingActionButtonSize.height;
最终双snackBarHeight=脚手架几何体.snackBarSize.height;
双fabY=contentBottom-fabHeight/2.0;
如果(蛇形杆高度>0.0)
fabY=math.min(fabY,contentBottom-snackBarHeight-fabHeight-kFloatingActionButtonMargin);
如果(appBarHeight>0.0)
fabY=math.min(fabY,contentBottom-appBarHeight-fabHeight/2.0);
最终double maxFabY=脚手架几何体.scaffoldSize.height-脚手架高度;
返回math.min(maxFabY,fabY);
}
}
不要使用内置的FAB,而是使用带有自己的圆形按钮的堆栈。在脚手架体内,您可以执行以下操作:
body: Stack(
children: <Widget>[
Container(
// whatever your main content is
),
Positioned(
top: 5.0,
right: 200.0, // or whatever
child: MyFAB,
),
],
),
现在,您可以使用堆栈中的定位小部件将晶圆厂定位到您想要的任何位置。谢谢,这对我很有用!然而,做得不那么复杂,把晶圆厂的25%和75%的宽度。
class MyFAB extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Container(
color: Colors.blue,
child: InkWell(
onTap: () => {},
borderRadius: BorderRadius.circular(50.0),
child: Container(
width: 45.0,
height: 45.0,
decoration: BoxDecoration(
shape: BoxShape.circle,
color: Colors.red,
),
child: Icon(
Icons.add,
color: Colors.yellow,
size: 25.0,
),
),
),
);
}
}