今天阐述uniapp开发中给启动图做延迟效果，不然启动图太快了，一闪就过去了；
一：修改配置文件：manifest.json
"app-plus" : {
"splashscreen" : {
"alwaysShowBeforeRender" : false,
"autoclose" : false,
"delay" : 3000, // 设置延时时间为3000毫秒
"waiting" : true
},
}
二：App.vue界面做一下处理
onLaunch() {
setTimeout(() => {
plus.navigator.closeSplashscreen();
}, 3000);
},
三：这个关闭掉
OK了，这样就好了，运行看看效果，完美！
启动图配置
1.下载官方给的模版，stroybord文件，然后解压！
2.LaunchScreen文件用Hbulider打开，并且进行适当的修改，具体的可以看里面的说明文件(redme.md)
LaunchScreen如下：
<?xml version="1.0" encoding="UTF-8"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="32700.99.1234" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
<device id="retina6_5" orientation="portrait" appearance="light"/>
<dependencies>
<deployment identifier="iOS"/>
<plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="22685"/>
<capability name="Safe area layout guides" minToolsVersion="9.0"/>
<capability name="System colors in document resources" minToolsVersion="11.0"/>
<capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>
<scenes>
<!--View Controller-->
<scene sceneID="EHf-IW-A2E">
<objects>
<viewController id="01J-lp-oVM" sceneMemberID="viewController">
<view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
<rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
<autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
<subviews>
<imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="dc_launchscreen_pad_background.png" translatesAutoresizingMaskIntoConstraints="NO" id="Oly-Jg-H5o">
<rect key="frame" x="0.0" y="0.0" width="1032" height="1376"/>
<color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
</imageView>
<imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="dc_launchscreen_landscape_background.png" translatesAutoresizingMaskIntoConstraints="NO" id="jN2-Td-r8h">
<rect key="frame" x="0.0" y="0.0" width="812" height="375"/>
<color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
</imageView>
<imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" image="dc_launchscreen_portrait_background.png" translatesAutoresizingMaskIntoConstraints="NO" id="Tt8-jS-2H5">
<rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
<color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
</imageView>
<label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="hello uniapp" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="QBH-Ne-rcx">
<rect key="frame" x="168" y="835" width="78.333333333333314" height="17"/>
<fontDescription key="fontDescription" type="system" pointSize="14"/>
<color key="textColor" white="0.66666666666666663" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
<nil key="highlightedColor"/>
</label>
</subviews>
<viewLayoutGuide key="safeArea" id="IW3-oA-Ytg"/>
<!-- <color key="backgroundColor" red="0.83516160100000003" green="0.88008347600000003" blue="0.88008347600000003" alpha="1" colorSpace="calibratedRGB"/> -->
<constraints>
<constraint firstAttribute="trailing" relation="greaterThanOrEqual" secondItem="vp6-uo-KS2" secondAttribute="trailing" id="1Cb-y2-pRQ"/>
<constraint firstItem="QBH-Ne-rcx" firstAttribute="bottom" secondItem="Ze5-6b-2t3" secondAttribute="bottom" constant="-44" id="5MD-Bb-oGe"/>
<constraint firstAttribute="trailing" secondItem="jN2-Td-r8h" secondAttribute="trailing" id="Bbg-68-h1T"/>
<constraint firstItem="Tt8-jS-2H5" firstAttribute="top" secondItem="Ze5-6b-2t3" secondAttribute="top" id="FH7-NM-QY8"/>
<constraint firstItem="vp6-uo-KS2" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="GM5-vc-qeO"/>
<constraint firstItem="jN2-Td-r8h" firstAttribute="leading" secondItem="Ze5-6b-2t3" secondAttribute="leading" id="J9z-eJ-GkK"/>
<constraint firstItem="vp6-uo-KS2" firstAttribute="top" relation="greaterThanOrEqual" secondItem="Ze5-6b-2t3" secondAttribute="top" constant="10" id="M4i-XX-uO2"/>
<constraint firstItem="jN2-Td-r8h" firstAttribute="top" secondItem="Ze5-6b-2t3" secondAttribute="top" id="QFR-Dp-WZN"/>
<constraint firstAttribute="trailing" secondItem="Tt8-jS-2H5" secondAttribute="trailing" id="QGW-bk-xBw"/>
<constraint firstItem="vp6-uo-KS2" firstAttribute="centerY" secondItem="Ze5-6b-2t3" secondAttribute="centerY" id="Qji-wc-LLD"/>
<constraint firstAttribute="bottom" secondItem="Oly-Jg-H5o" secondAttribute="bottom" id="RrE-yv-HsN"/>
<constraint firstItem="Oly-Jg-H5o" firstAttribute="top" secondItem="Ze5-6b-2t3" secondAttribute="top" id="VcW-dk-n8h"/>
<constraint firstAttribute="bottom" relation="greaterThanOrEqual" secondItem="vp6-uo-KS2" secondAttribute="bottom" constant="10" id="dGX-JM-hiU"/>
<constraint firstItem="Oly-Jg-H5o" firstAttribute="leading" secondItem="Ze5-6b-2t3" secondAttribute="leading" id="fa7-4C-n5e"/>
<constraint firstItem="Tt8-jS-2H5" firstAttribute="leading" secondItem="Ze5-6b-2t3" secondAttribute="leading" id="fnt-hE-VMi"/>
<constraint firstAttribute="bottom" secondItem="jN2-Td-r8h" secondAttribute="bottom" id="iIX-Hl-IOF"/>
<constraint firstAttribute="trailing" secondItem="Oly-Jg-H5o" secondAttribute="trailing" id="mm9-f4-toK"/>
<constraint firstItem="vp6-uo-KS2" firstAttribute="leading" relation="greaterThanOrEqual" secondItem="Ze5-6b-2t3" secondAttribute="leading" id="oA2-4f-IGA"/>
<constraint firstItem="QBH-Ne-rcx" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="rO7-2t-bpH"/>
<constraint firstAttribute="bottom" secondItem="Tt8-jS-2H5" secondAttribute="bottom" id="seh-wj-zPF"/>
</constraints>
<variation key="default">
<mask key="subviews">
<exclude reference="Oly-Jg-H5o"/>
<exclude reference="jN2-Td-r8h"/>
<exclude reference="Tt8-jS-2H5"/>
</mask>
</variation>
<variation key="heightClass=compact">
<mask key="subviews">
<include reference="jN2-Td-r8h"/>
</mask>
</variation>
<variation key="heightClass=regular-widthClass=compact">
<mask key="subviews">
<include reference="Tt8-jS-2H5"/>
</mask>
</variation>
<variation key="heightClass=regular-widthClass=regular">
<mask key="subviews">
<include reference="Oly-Jg-H5o"/>
</mask>
</variation>
</view>
</viewController>
<placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
</objects>
<point key="canvasLocation" x="52.173913043478265" y="374.33035714285711"/>
</scene>
</scenes>
<resources>
<image name="dc_launchscreen_portrait_background.png" width="375" height="812"/>
<!-- <systemColor name="systemBackgroundColor">
<color white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
</systemColor> -->
</resources>
</document>
3.把启动图xxx@2x，xxx@3x直接放到项目下，不要放images文件下：
4.云打包测试，只有打包后才能看到效果；
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