Just use https://romannurik.github.io/AndroidAssetStudio/index.html. It can make a set of icons from an image, later you can download a zip-file. Or download a Windows application at https://github.com/redwarp/9-Patch-Resizer/releases (doesn't need to install) and open an icon. Also you can use a plugin Android Drawable Importer, see answers above. Because it is abandoned, install forks. See Why does Android Drawable Importer ignore selection in AS 3.5 onwards or https://github.com/Vincent-Loi/android-drawable-importer-intellij-plugin. https://appicon.co/#image-sets.

Just use https://romannurik.github.io/AndroidAssetStudio/index.html. It can make a set of icons from an image, later you can download a zip-file. Or download a Windows application at https://github.com/redwarp/9-Patch-Resizer/releases (doesn't need to install) and open an icon. Also you can use a plugin Android Drawable Importer, see answers above. Because it is abandoned, install forks. See Why does Android Drawable Importer ignore selection in AS 3.5 onwards or https://github.com/Vincent-Loi/android-drawable-importer-intellij-plugin. https://appicon.co/#image-sets.

更新:

之前提到的插件已经被放弃了，但它显然有一个最新的分支。

旧的回答:

我使用名为Android Drawable Importer的Android Studio插件:

要在安装后使用它，右键单击您的res/drawable文件夹，并选择New > Batch drawable Import:

然后通过+按钮选择你的图像，并将分辨率设置为xxhdpi(或任何你的源图像的分辨率)。

Android中一个简单的插件就能帮到你 步骤1。进入设置 步骤2。点击插件 步骤3。搜索Android Drawable Importer 步骤4。安装插件并重新启动

如何使用?

进入“文件>新建>批量可绘制导入”

享受

使用像Image Baker这样的在线服务。

这很简单。在Android和iOS上上传图片和下载处理过的资产。

注:Image Baker是我的朋友和我自己创建的免费服务。

一个bash脚本使用ImageMagick(转换)根据CommonsWare的答案:

增加了文件夹创建和参数检查多亏了Kishan Vaghela

#!/bin/sh
#---------------------------------------------------------------
# Given an xxhdpi image or an App Icon (launcher), this script
# creates different dpis resources and the necessary folders
# if they don't exist
#
# Place this script, as well as the source image, inside res
# folder and execute it passing the image filename as argument
#
# Example:
# ./drawables_dpis_creation.sh ic_launcher.png
# OR
# ./drawables_dpis_creation.sh my_cool_xxhdpi_image.png
#
# Copyright (c) 2016 Ricardo Romao.
# This free software comes with ABSOLUTELY NO WARRANTY and
# is distributed under GNU GPL v3 license. 
#---------------------------------------------------------------

if [ $# -eq 0 ]; then
    echo "No arguments supplied"
else if [ -f "$1" ]; then
    echo " Creating different dimensions (dips) of "$1" ..."
    mkdir -p drawable-xxxhdpi
    mkdir -p drawable-xxhdpi
    mkdir -p drawable-xhdpi
    mkdir -p drawable-hdpi
    mkdir -p drawable-mdpi

    if [ $1 = "ic_launcher.png" ]; then
        echo "  App icon detected"
        convert ic_launcher.png -resize 144x144 drawable-xxhdpi/ic_launcher.png
        convert ic_launcher.png -resize 96x96 drawable-xhdpi/ic_launcher.png
        convert ic_launcher.png -resize 72x72 drawable-hdpi/ic_launcher.png
        convert ic_launcher.png -resize 48x48 drawable-mdpi/ic_launcher.png
        rm -i ic_launcher.png
    else
        convert $1 -resize 75% drawable-xxhdpi/$1
        convert $1 -resize 50% drawable-xhdpi/$1
        convert $1 -resize 38% drawable-hdpi/$1
        convert $1 -resize 25% drawable-mdpi/$1
        mv $1 drawable-xxxhdpi/$1
    fi
echo " Done"
else
    echo "$1 not found."
fi
fi