There are instructions for other platforms linked from the get the code page.
Are you a Google employee? See go/building-chrome instead.
Most development is done on Ubuntu. Other distros may or may not work; see the Linux instructions for some suggestions.
Building the Android client on Windows or Mac is not supported and doesn't work.
depot_toolsClone the depot_tools repository:
$ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
Add depot_tools to the end of your PATH (you will probably want to put this in your ~/.bashrc or ~/.zshrc). Assuming you cloned depot_tools to /path/to/depot_tools:
$ export PATH="$PATH:/path/to/depot_tools"
Create a chromium directory for the checkout and change to it (you can call this whatever you like and put it wherever you like, as long as the full path has no spaces):
$ mkdir ~/chromium && cd ~/chromium $ fetch --nohooks android
If you don't want the full repo history, you can save a lot of time by adding the --no-history flag to fetch.
Expect the command to take 30 minutes on even a fast connection, and many hours on slower ones.
If you've already installed the build dependencies on the machine (from another checkout, for example), you can omit the --nohooks flag and fetch will automatically execute gclient runhooks at the end.
When fetch completes, it will have created a hidden .gclient file and a directory called src in the working directory. The remaining instructions assume you have switched to the src directory:
$ cd src
If you have an existing Linux checkout, you can add Android support by appending target_os = ['android'] to your .gclient file (in the directory above src):
$ echo "target_os = [ 'android' ]" >> ../.gclient
Then run gclient sync to pull the new Android dependencies:
$ gclient sync
(This is the only difference between fetch android and fetch chromium.)
Once you have checked out the code, run
$ build/install-build-deps-android.sh
to get all of the dependencies you need to build on Linux, plus all of the Android-specific dependencies (you need some of the regular Linux dependencies because an Android build includes a bunch of the Linux tools and utilities).
Once you've run install-build-deps at least once, you can now run the Chromium-specific hooks, which will download additional binaries and other things you might need:
$ gclient runhooks
Optional: You can also install API keys if you want your build to talk to some Google services, but this is not necessary for most development and testing purposes.
Chromium uses Ninja as its main build tool along with a tool called GN to generate .ninja files. You can create any number of build directories with different configurations. To create a build directory which builds Chrome for Android, run:
$ gn gen --args='target_os="android"' out/Default
Default with another name, but it should be a subdirectory of out.gn help on the command line or read the quick start guide.Also be aware that some scripts (e.g. tombstones.py, adb_gdb.py) require you to set CHROMIUM_OUTPUT_DIR=out/Default.
Build Chromium with Ninja using the command:
$ ninja -C out/Default chrome_public_apk
You can get a list of all of the other build targets from GN by running gn ls out/Default from the command line. To compile one, pass the GN label to Ninja with no preceding “//” (so, for //chrome/test:unit_tests use ninja -C out/Default chrome/test:unit_tests).
If the adb_install_apk.py script below fails, make sure aapt is in your PATH. If not, add aapt's parent directory to your PATH environment variable (it should be /path/to/src/third_party/android_tools/sdk/build-tools/{latest_version}/).
Prepare the environment:
$ . build/android/envsetup.sh
Make sure your Android device is plugged in via USB, and USB Debugging is enabled.
To enable USB Debugging:
You may also be prompted to allow access to your PC once your device is plugged in.
You can check if the device is connected by running:
third_party/android_tools/sdk/platform-tools/adb devices
Which prints a list of connected devices. If not connected, try unplugging and reattaching your device.
ninja -C out/Default chrome_public_apk
And deploy it to your Android device:
build/android/adb_install_apk.py out/Default/apks/ChromePublic.apk
The app will appear on the device as “Chromium”.
Wraps the content module (but not the /chrome embedder). See https://www.chromium.org/developers/content-module for details on the content module and content shell.
ninja -C out/Default content_shell_apk build/android/adb_install_apk.py out/Default/apks/ContentShell.apk
this will build and install an Android apk under out/Default/apks/ContentShell.apk.
If you use custom out dir instead of standard out/ dir, use CHROMIUM_OUT_DIR env.
export CHROMIUM_OUT_DIR=out_android
Android WebView is a system framework component. Since Android KitKat, it is implemented using Chromium code (based off the content module).
If you want to build the complete Android WebView framework component and test the effect of your chromium changes in Android apps using WebView, you should follow the Android AOSP + chromium WebView instructions
Set command line flags if necessary.
For Content shell:
build/android/adb_run_content_shell http://example.com
For Chrome public:
build/android/adb_run_chrome_public http://example.com
Logging is often the easiest way to understand code flow. In C++ you can print log statements using the LOG macro or printf(). In Java, you can print log statements using android.util.Log:
Log.d("sometag", "Reticulating splines progress = " + progress);
You can see these log statements using adb logcat:
adb logcat...01-14 11:08:53.373 22693 23070 D sometag: Reticulating splines progress = 0.99
You can debug Java or C++ code. To debug C++ code, use one of the following commands:
build/android/adb_gdb_content_shell build/android/adb_gdb_chrome_public
See Android Debugging Instructions for more on debugging, including how to debug Java code.
For information on running tests, see Android Test Instructions.
GN's “incremental install” uses reflection and side-loading to speed up the edit & deploy cycle (normally < 10 seconds). The initial launch of the apk will be a little slower since updated dex files are installed manually.
is_component_build = truein your GN args_incremental targets defined (e.g. chrome_public_apk_incremental) except for Webview and MonochromeHere's an example:
ninja -C out/Default chrome_public_apk_incremental out/Default/bin/install_chrome_public_apk_incremental -v
For gunit tests (note that run_*_incremental automatically add --fast-local-dev when calling test_runner.py):
ninja -C out/Default base_unittests_incremental out/Default/bin/run_base_unittests_incremental
For instrumentation tests:
ninja -C out/Default chrome_public_test_apk_incremental out/Default/bin/run_chrome_public_test_apk_incremental
To uninstall:
out/Default/bin/install_chrome_public_apk_incremental -v --uninstall
A subtly erroneous flow arises when you build a regular apk but install an incremental apk (e.g. ninja -C out/Default foo_apk && out/Default/bin/install_foo_apk_incremental). Setting incremental_apk_by_default = true in your GN args aliases regular targets as their incremental counterparts. With this arg set, the commands above become:
ninja -C out/Default chrome_public_apk out/Default/bin/install_chrome_public_apk ninja -C out/Default base_unittests out/Default/bin/run_base_unittests ninja -C out/Default chrome_public_test_apk out/Default/bin/run_chrome_public_test_apk
If you want to build a non-incremental apk you'll need to remove incremental_apk_by_default from your GN args.
These instructions are only necessary for Chrome 51 and earlier.
In the case where you want to modify the native code for an existing release of Chrome for Android (v25+) you can do the following steps. Note that in order to get your changes into the official release, you'll need to send your change for a codereview using the regular process for committing code to chromium.