我想要一个让我的用户通过身份验证流程的对话框。它将需要以下小部件:
我想做的是创建一个带有 PageView 小部件的 AlertDialog，它将通过 PageController 进行导航(我设置了 physics: NeverScrollableScrollPhysics() 以防止用户滚动)。这里的整个想法是我希望对话框始终保持相同的大小(据我所知，PageView 将测量所有子项并且应该允许我这样做。
我尝试使用 3 个 Text 小部件创建 PageView，但出现以下错误:
I/flutter (16052): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (16052): The following assertion was thrown during performLayout():
I/flutter (16052): RenderViewport does not support returning intrinsic dimensions.
I/flutter (16052): Calculating the intrinsic dimensions would require instantiating every child of the viewport, which
I/flutter (16052): defeats the point of viewports being lazy.
I/flutter (16052): If you are merely trying to shrink-wrap the viewport in the main axis direction, consider a
I/flutter (16052): RenderShrinkWrappingViewport render object (ShrinkWrappingViewport widget), which achieves that
I/flutter (16052): effect without implementing the intrinsic dimension API.
I/flutter (16052):
I/flutter (16052): When the exception was thrown, this was the stack:
I/flutter (16052): #0 RenderViewportBase.debugThrowIfNotCheckingIntrinsics.<anonymous closure> (package:flutter/src/rendering/viewport.dart:299:9)
I/flutter (16052): #1 RenderViewportBase.debugThrowIfNotCheckingIntrinsics (package:flutter/src/rendering/viewport.dart:309:6)
I/flutter (16052): #2 RenderViewportBase.computeMaxIntrinsicWidth (package:flutter/src/rendering/viewport.dart:321:12)
I/flutter (16052): #3 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #4 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #5 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #6 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #7 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #8 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #9 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #10 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #11 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #12 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #13 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #14 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #15 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #16 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #17 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #18 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #19 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #20 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #21 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #22 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #23 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #24 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #25 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #26 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #27 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #28 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #29 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #30 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #31 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #32 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #33 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #34 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #35 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #36 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #37 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #38 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #39 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #40 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #41 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #42 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.computeMaxIntrinsicWidth (package:flutter/src/rendering/proxy_box.dart:76:20)
I/flutter (16052): #43 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #44 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #45 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #46 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #47 RenderPadding.computeMaxIntrinsicWidth (package:flutter/src/rendering/shifted_box.dart:163:20)
I/flutter (16052): #48 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #49 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #50 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #51 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #52 RenderFlex.computeMaxIntrinsicWidth.<anonymous closure> (package:flutter/src/rendering/flex.dart:575:60)
I/flutter (16052): #53 RenderFlex._getIntrinsicSize (package:flutter/src/rendering/flex.dart:552:58)
I/flutter (16052): #54 RenderFlex.computeMaxIntrinsicWidth (package:flutter/src/rendering/flex.dart:572:12)
I/flutter (16052): #55 RenderBox._computeIntrinsicDimension.<anonymous closure> (package:flutter/src/rendering/box.dart:1099:23)
I/flutter (16052): #56 __InternalLinkedHashMap&_HashVMBase&MapMixin&_LinkedHashMapMixin.putIfAbsent (dart:collection/runtime/libcompact_hash.dart:284:23)
I/flutter (16052): #57 RenderBox._computeIntrinsicDimension (package:flutter/src/rendering/box.dart:1097:41)
I/flutter (16052): #58 RenderBox.getMaxIntrinsicWidth (package:flutter/src/rendering/box.dart:1281:12)
I/flutter (16052): #59 RenderIntrinsicWidth.performLayout (package:flutter/src/rendering/proxy_box.dart:617:36)
I/flutter (16052): #60 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #61 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #62 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #63 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #64 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #65 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #66 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #67 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #68 _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1188:11)
I/flutter (16052): #69 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #70 RenderConstrainedBox.performLayout (package:flutter/src/rendering/proxy_box.dart:258:13)
I/flutter (16052): #71 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #72 RenderPositionedBox.performLayout (package:flutter/src/rendering/shifted_box.dart:385:13)
I/flutter (16052): #73 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #74 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11)
I/flutter (16052): #75 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #76 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11)
I/flutter (16052): #77 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #78 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #79 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #80 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #81 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #82 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #83 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #84 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #85 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #86 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #87 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #88 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #89 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #90 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
I/flutter (16052): #91 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2881:13)
I/flutter (16052): #92 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
I/flutter (16052): #93 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15)
I/flutter (16052): #94 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1509:7)
I/flutter (16052): #95 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:768:18)
I/flutter (16052): #96 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:281:19)
I/flutter (16052): #97 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:677:13)
I/flutter (16052): #98 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:219:5)
I/flutter (16052): #99 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15)
I/flutter (16052): #100 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9)
I/flutter (16052): #101 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:842:5)
I/flutter (16052): #102 _invoke (dart:ui/hooks.dart:154:13)
I/flutter (16052): #103 _drawFrame (dart:ui/hooks.dart:143:3)
I/flutter (16052):
I/flutter (16052): The following RenderObject was being processed when the exception was fired:
I/flutter (16052): RenderIntrinsicWidth#88cfa relayoutBoundary=up6 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): creator: IntrinsicWidth ← Semantics ← DefaultTextStyle ← AnimatedDefaultTextStyle ←
I/flutter (16052): _InkFeatures-[GlobalKey#8e5bb ink renderer] ← NotificationListener<LayoutChangedNotification> ←
I/flutter (16052): CustomPaint ← _ShapeBorderPaint ← PhysicalShape ← _MaterialInterior ← Material ← ConstrainedBox ←
I/flutter (16052): ⋯
I/flutter (16052): parentData: <none> (can use size)
I/flutter (16052): constraints: BoxConstraints(280.0<=w<=331.4, 0.0<=h<=611.4)
I/flutter (16052): size: MISSING
I/flutter (16052): stepWidth: null
I/flutter (16052): stepHeight: null
I/flutter (16052): This RenderObject had the following descendants (showing up to depth 5):
I/flutter (16052): RenderFlex#1cdae NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderPadding#3c952 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderRepaintBoundary#2e299 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderCustomPaint#4dd7f NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderRepaintBoundary#ebf6b NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderPadding#31e20 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderFlex#8072a NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderPadding#a5f11 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): RenderSemanticsAnnotations#f63f2 NEEDS-LAYOUT NEEDS-PAINT
I/flutter (16052): ════════════════════════════════════════════════════════════════════════════════════════════════════
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: RenderIntrinsicWidth#88cfa relayoutBoundary=up6 NEEDS-PAINT
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: RenderSemanticsAnnotations#ca67f relayoutBoundary=up5 NEEDS-PAINT
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: _RenderInkFeatures#a2ca4 relayoutBoundary=up4 NEEDS-PAINT
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: RenderCustomPaint#b4d9b relayoutBoundary=up3 NEEDS-PAINT
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: RenderPhysicalShape#235a2 relayoutBoundary=up2 NEEDS-PAINT
I/flutter (16052): Another exception was thrown: 'package:flutter/src/rendering/shifted_box.dart': Failed assertion: line 314 pos 12: 'child.hasSize': is not true.
I/flutter (16052): Another exception was thrown: RenderBox was not laid out: RenderPhysicalShape#235a2 relayoutBoundary=up2
如果有更好的方法来做到这一点，只要对话框不会调整大小，我愿意接受。
更新:
这是一个最小的示例，只需启动以下对话框:
AlertDialog(
content: PageView(
children: <Widget> [
Text('child1'),
Text('child2'),
Text('child3'),
],
),
);
问题似乎是 PageView 没有立即实例化所有 View ，而是延迟实例化以节省 CPU 周期。这意味着 AlertDialog 无法自行调整大小。我想弄清楚是否有一种方法可以覆盖 PageView 的默认行为并让它立即测量其大小？
更新:
虽然我无法使用 PageView 执行任何操作，但我已经能够使用简单的 IndexedStack 来模仿我想要的行为。它只是缺少以编程方式在页面之间移动时的动画，但希望我能够添加它。完成后我会发布最终答案。
最佳答案
只需用 Container 包装您的 PageView 并指定其宽度和高度即可。
AlertDialog(
Container(
width: width,
height: height,
child: PageView(
...
),
),
)
关于flutter - 有没有办法在 Flutter 中使用 PageView 创建一个 AlertDialog？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/54012407/
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假设我做了一个模块如下:m=Module.newdoclassCendend三个问题:除了对m的引用之外，还有什么方法可以访问C和m中的其他内容？我可以在创建匿名模块后为其命名吗(就像我输入“module...”一样)？如何在使用完匿名模块后将其删除，使其定义的常量不再存在？ 最佳答案 三个答案:是的，使用ObjectSpace.此代码使c引用你的类(class)C不引用m:c=nilObjectSpace.each_object{|obj|c=objif(Class===objandobj.name=~/::C$/)}当然这取决于
出于纯粹的兴趣，我很好奇如何按顺序创建PI，而不是在过程结果之后生成数字，而是让数字在过程本身生成时显示。如果是这种情况，那么数字可以自行产生，我可以对以前看到的数字实现垃圾收集，从而创建一个无限系列。结果只是在Pi系列之后每秒生成一个数字。这是我通过互联网筛选的结果:这是流行的计算机友好算法，类机器算法:defarccot(x,unity)xpow=unity/xn=1sign=1sum=0loopdoterm=xpow/nbreakifterm==0sum+=sign*(xpow/n)xpow/=x*xn+=2sign=-signendsumenddefcalc_pi(digits
我正在尝试使用ruby和Savon来使用网络服务。测试服务为http://www.webservicex.net/WS/WSDetails.aspx?WSID=9&CATID=2require'rubygems'require'savon'client=Savon::Client.new"http://www.webservicex.net/stockquote.asmx?WSDL"client.get_quotedo|soap|soap.body={:symbol=>"AAPL"}end返回SOAP异常。检查soap信封，在我看来soap请求没有正确的命名空间。任何人都可以建议我
关闭。这个问题是opinion-based.它目前不接受答案。想要改进这个问题？更新问题，以便editingthispost可以用事实和引用来回答它.关闭4年前。Improvethisquestion我想在固定时间创建一系列低音和高音调的哔哔声。例如:在150毫秒时发出高音调的蜂鸣声在151毫秒时发出低音调的蜂鸣声200毫秒时发出低音调的蜂鸣声250毫秒的高音调蜂鸣声有没有办法在Ruby或Python中做到这一点？我真的不在乎输出编码是什么(.wav、.mp3、.ogg等等)，但我确实想创建一个输出文件。
我在我的项目目录中完成了compasscreate.和compassinitrails。几个问题:我已将我的.sass文件放在public/stylesheets中。这是放置它们的正确位置吗？当我运行compasswatch时，它不会自动编译这些.sass文件。我必须手动指定文件:compasswatchpublic/stylesheets/myfile.sass等。如何让它自动运行？文件ie.css、print.css和screen.css已放在stylesheets/compiled。如何在编译后不让它们重新出现的情况下删除它们？我自己编译的.sass文件编译成compiled/t
我想将html转换为纯文本。不过，我不想只删除标签，我想智能地保留尽可能多的格式。为插入换行符标签，检测段落并格式化它们等。输入非常简单，通常是格式良好的html(不是整个文档，只是一堆内容，通常没有anchor或图像)。我可以将几个正则表达式放在一起，让我达到80%，但我认为可能有一些现有的解决方案更智能。 最佳答案 首先，不要尝试为此使用正则表达式。很有可能你会想出一个脆弱/脆弱的解决方案，它会随着HTML的变化而崩溃，或者很难管理和维护。您可以使用Nokogiri快速解析HTML并提取文本:require'nokogiri'h