====== Flutter / debug ======

  * Dart & Flutter support for Visual Studio Code [[https://dartcode.org/docs/debugging-commands/|Debugging Commands]]

===== Attraper un maximum d'erreurs =====

{{ :informatique:flutter:debug_catch_max_errors.png?nolink&400 |}}

===== Le rendu plante sans rien dans la debug console =====

Le rendu ne va pas, il plante sans rien "//dire//" **(1)** et aucune erreur dans la "debug console".
On observe dans la partie "call stack" **(2)** le message en rouge "Paused on exception", c'est là qui faut dire au debugger de continuer "Continue (F5)" **(3)** pour voir apparaître les détails de l'erreur **(4)**.

{{:informatique:flutter:debug_rendering_01.png?nolink&300|}}
{{:informatique:flutter:debug_rendering_02.png?nolink&400|}}
{{:informatique:flutter:debug_rendering_03.png?nolink&400|}}

Par exemple un ''ListView'' dans un ''Column'' génère l'erreur, avec souvent une explication.

<code>
════════ Exception caught by rendering library ═════════════════════════════════
The following assertion was thrown during performResize():
Vertical viewport was given unbounded height.
Viewports expand in the scrolling direction to fill their container. In this case, a vertical viewport was given an unlimited amount of vertical space in which to expand. This situation typically happens when a scrollable widget is nested inside another scrollable widget.
If this widget is always nested in a scrollable widget there is no need to use a viewport because there will always be enough vertical space for the children. In this case, consider using a Column or Wrap instead. Otherwise, consider using a CustomScrollView to concatenate arbitrary slivers into a single scrollable.

The relevant error-causing widget was:
    ListView ListView:file:///home/.../CroustiWiki.flutter/lib/widgets/duks_list.dart:53:27

...

════════ Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderViewport#6f0f6 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 2251 pos 12: 'hasSize'
The relevant error-causing widget was:
    ListView ListView:file:///home/.../CroustiWiki.flutter/lib/widgets/duks_list.dart:53:27
════════════════════════════════════════════════════════════════════════════════
</code>