创建图标
一些术语
full bleed：A full bleed image extends or “bleeds” to the edges of a page so that the image completely covers the entire page and does not show borders or white space around the edges. We’ll show you what a full bleed layout looks like in BookSmart and how to best position your full bleed images.
Rounded square/Squircle：
A shape similar to a squircle, called a rounded square, may be generated by separating four quarters of a circle and connecting their loose ends with straight lines, or by separating the four sides of a square and connecting them with quarter-circles. Such a shape is very similar but not identical to the squircle.
操作
Right-click the res folder and select New > Image Asset.
debug的文件名改动
在build.gradle（module）的android下面添加
android.applicationVariants.all { variant ->
variant.outputs.all {
def appName = “oxford”
def date = new Date()
def formattedDate = date.format(‘yyyy-MM-dd hh mm’)
outputFileName = appName + “.apk”
}
}
困扰我1个小时的问题。在android10访问目录的时候会有报错（open failed: EACCES (Permission denied)），方法就是在application中写入 android:requestLegacyExternalStorage=“true”