After some existencial questions on how the gray level colors should be defined in our android projects, I’ve decided to check the predefined colors on the android platform:

$ find . -type f -name "colors.xml" -print0 | xargs -0 grep grey
$ find . -type f -name "colors.xml" -print0 | xargs -0 grep gray
./platforms/android-4/data/res/values/colors.xml:    <color name="lighter_gray">#ddd</color>
./platforms/android-4/data/res/values/colors.xml:    <color name="darker_gray">#aaa</color>
[…]
./platforms/android-10/data/res/values/colors.xml:    <color name="lighter_gray">#ddd</color>
./platforms/android-10/data/res/values/colors.xml:    <color name="darker_gray">#aaa</color>
[…]

Ok, the first conclusion is that the android platform definetely used a US convention… No surprises there. Two gray level colors are defined in platforms. Now, I should check on the android developers website: here and there and search for gray level colors. According to this documentation, only darker_gray seems to be public, although lighter_gray is defined within data/res/values/colors.xml…

Ok, make a sample stupid project:

$ android create project --name Grayish \
 --target android-10 --path /foo/bar/Grayish \
 --package org.summo.grayish --activity MyLifeInGray

Let’s define some colors in the project res/values/colors.xml file:

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<?xml version="1.0" encoding="utf-8"?>
<resources>
  <color name="lighter_gray">#ddd</color>
  <color name="darker_gray">#aaa</color>
  <color name="gray_40">#696969</color>
</resources>

Use them (res/layout/main.xml file):

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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent" >
  <TextView
      android:background="@android:color/darker_gray"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="@android:color/darker_gray"
      android:textColor="@android:color/black"
      />
  <TextView
      android:background="@color/lighter_gray"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="@color/lighter_gray"
      android:textColor="@android:color/black"
      />
  <TextView
      android:background="@color/darker_gray"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="@color/darker_gray"
      android:textColor="@android:color/black"
      />
  <TextView
      android:background="@color/gray_40"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="@color/gray_40"
      android:textColor="@android:color/black"
      />
</LinearLayout>

Compile and install the project on your device:

$ ant install

A ddms screenshot and a cropping later:

That’s weird but lighter_gray is not public… We have access to only one gray system color! To conclude: although we could use the system colors, and since one and only one color is just useless, we would rather define lighter_gray and darker_gray in our own res/values/colors.xml file and if we need more grayish colors, we would use a gray_xx, xx corresponding to the percentage of white color.

Et voilà !