一、图片问题 Unable to load asset: images/bg.png ？
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======== Exception caught by image resource service ================================================
The following assertion was thrown resolving an image codec:
Unable to load asset: images/bg.png
When the exception was thrown, this was the stack:
#0 PlatformAssetBundle.load (package:flutter/src/services/asset_bundle.dart:227:7)
<asynchronous suspension>
#1 AssetBundleImageProvider._loadAsync (package:flutter/src/painting/image_provider.dart:667:14)
<asynchronous suspension>
Image provider: AssetImage(bundle: null, name: "images/bg.png")
Image key: AssetBundleImageKey(bundle: PlatformAssetBundle#ae84f(), name: "images/bg.png", scale: 1.0)
====================================================================================================
解决方案：
-
pubspec.yaml中，assets:需要和uses-material-design: true对齐 -
- 根目录/bg.png，文件需从根目录开始引用 - 引用也需要从根目录开始
body: Image.asset('根目录/bg.png'),
二、@1x @2x @3x 适配？
解决方案:
在
images/目录下生成2.0x、3.0x文件夹assets中引用- images/2.0x/图片.png、- images/3.0x/图片.png
三、声明所有图片？
解决方案:
在assets 中 只声明 文件夹名称，系统会自动适配。
assets:
- images/
- images/2.0x/
- images/3.0x/
四、图片如何 铺满全屏？
解决方案：
Image.asset(
'images/bg.png',
fit: BoxFit.fill,
width: double.infinity,
height: double.infinity,
),
单独铺满 BoxFit.fill 无效，需要配合 width，height来适配全屏幕。这里 double.infinity表示最大值。
infinity 的值为:
static const double infinity = 1.0 / 0.0;
数学上 分母不为零，在Flutter，表示无限大。
五、如何设置背景图片？
解决方案：
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage(
'images/bg.png', // 背景图片
),
fit: BoxFit.fill,
),
),
),
