docs/android_build_instructions.md - chromium/src.git - Git at Google

 # Checking out and building Chromium for Android

 There are instructions for other platforms linked from the
 [get the code](get_the_code.md) page.

 ## Instructions for Google Employees

 Are you a Google employee? See
 [go/building-chrome](https://goto.google.com/building-chrome) instead.

 [TOC]

 ## System requirements

 * A 64-bit Intel machine running Linux with at least 8GB of RAM. More
   than 16GB is highly recommended.
 * At least 100GB of free disk space.
 * You must have Git and Python installed already.

 Most development is done on Ubuntu. Other distros may or may not work;
 see the [Linux instructions](linux_build_instructions.md) for some suggestions.

 Building the Android client on Windows or Mac is not supported and doesn't work.

 ## Install `depot_tools`

 Clone the `depot_tools` repository:

 ```shell
 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`:

 ```shell
 export PATH="$PATH:/path/to/depot_tools"
 ```

 ## Get the code

 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):

 ```shell
 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:

 ```shell
 cd src
 ```

 ### Converting an existing Linux checkout

 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`):

 ```shell
 echo "target_os = [ 'android' ]" >> ../.gclient
 ```

 Then run `gclient sync` to pull the new Android dependencies:

 ```shell
 gclient sync
 ```

 (This is the only difference between `fetch android` and `fetch chromium`.)

 ### Install additional build dependencies

 Once you have checked out the code, run

 ```shell
 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).

 ### Run the hooks

 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:

 ```shell
 gclient runhooks
 ```

 *Optional*: You can also [install API
 keys](https://www.chromium.org/developers/how-tos/api-keys) if you want your
 build to talk to some Google services, but this is not necessary for most
 development and testing purposes.

 ## Setting up the build

 Chromium uses [Ninja](https://ninja-build.org) as its main build tool along
 with a tool called [GN](../tools/gn/docs/quick_start.md) 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:

 ```shell
 gn gen --args='target_os="android"' out/Default
 ```

 * You only have to run this once for each new build directory, Ninja will
   update the build files as needed.
 * You can replace `Default` with another name, but
   it should be a subdirectory of `out`.
 * For other build arguments, including release settings, see [GN build
   configuration](https://www.chromium.org/developers/gn-build-configuration).
   The default will be a debug component build matching the current host
   operating system and CPU.
 * For more info on GN, run `gn help` on the command line or read the
   [quick start guide](../tools/gn/docs/quick_start.md).

 Also be aware that some scripts (e.g. `tombstones.py`, `adb_gdb.py`)
 require you to set `CHROMIUM_OUTPUT_DIR=out/Default`.

 ## Build Chromium

 Build Chromium with Ninja using the command:

 ```shell
 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`).

 ## Installing and Running Chromium on a device

 Prepare the environment:

 ```shell
 . build/android/envsetup.sh
 ```

 ### Plug in your Android device

 Make sure your Android device is plugged in via USB, and USB Debugging
 is enabled.

 To enable USB Debugging:

 *   Navigate to Settings \> About Phone \> Build number
 *   Click 'Build number' 7 times
 *   Now navigate back to Settings \> Developer Options
 *   Enable 'USB Debugging' and follow the prompts

 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:

 ```shell
 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.

 ### Build the full browser

 ```shell
 ninja -C out/Default chrome_public_apk
 ```

 And deploy it to your Android device:

 ```shell
 out/Default/bin/chrome_public_apk install
 ```

 The app will appear on the device as "Chromium".

 ### Build Content shell

 Wraps the content module (but not the /chrome embedder). See
 [https://www.chromium.org/developers/content-module](https://www.chromium.org/developers/content-module)
 for details on the content module and content shell.

 ```shell
 ninja -C out/Default content_shell_apk
 out/Default/bin/content_shell_apk install
 ```

 this will build and install an Android apk under
 `out/Default/apks/ContentShell.apk`.

 ### Build WebView

 [Android WebView](https://developer.android.com/reference/android/webkit/WebView.html)
 is a system framework component. Since Android KitKat, it is implemented using
 Chromium code (based off the [content module](https://dev.chromium.org/developers/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](https://www.chromium.org/developers/how-tos/build-instructions-android-webview)

 ### Running

 For Content shell:

 ```shell
 out/Default/bin/content_shell_apk launch [--args='--foo --bar'] http://example.com
 ```

 For Chrome public:

 ```shell
 out/Default/bin/chrome_public_apk launch [--args='--foo --bar'] http://example.com
 ```

 ### Logging and debugging

 Logging is often the easiest way to understand code flow. In C++ you can print
 log statements using the LOG macro. In Java, refer to
 [android_logging.md](android_logging.md).

 You can see these log via `adb logcat`, or:

 ```shell
 out/Default/bin/chrome_public_apk logcat
 ```

 To debug C++ code, use one of the following commands:

 ```shell
 out/Default/bin/content_shell_apk gdb
 out/Default/bin/chrome_public_apk gdb
 ```

 See [Android Debugging Instructions](android_debugging_instructions.md)
 for more on debugging, including how to debug Java code.

 ### Testing

 For information on running tests, see [Android Test Instructions](android_test_instructions.md).

 ### Faster Edit/Deploy

 "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.

 *   Make sure to set` is_component_build = true `in your GN args
 *   All apk targets have \*`_incremental` targets defined (e.g.
     `chrome_public_apk_incremental`) except for Webview and Monochrome

 Here's an example:

 ```shell
 ninja -C out/Default chrome_public_apk_incremental
 out/Default/bin/chrome_public_apk install --incremental --verbose
 ```

 For gunit tests (note that run_*_incremental automatically add
 `--fast-local-dev` when calling `test_runner.py`):

 ```shell
 ninja -C out/Default base_unittests_incremental
 out/Default/bin/run_base_unittests_incremental
 ```

 For instrumentation tests:

 ```shell
 ninja -C out/Default chrome_public_test_apk_incremental
 out/Default/bin/run_chrome_public_test_apk_incremental
 ```

 To uninstall:

 ```shell
 out/Default/bin/chrome_public_apk uninstall
 ```

 To avoid typing `_incremental` when building targets, you can use the GN arg:

 ```
 incremental_apk_by_default = true
 ```

 This will make `chrome_public_apk` build in incremental mode.


 ## Tips, tricks, and troubleshooting

 ### Rebuilding libchrome.so for a particular release

 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.

 1.  Open Chrome on your Android device and visit chrome://version
 2.  Copy down the id listed next to "Build ID:"
 3.  Go to
     [http://storage.googleapis.com/chrome-browser-components/BUILD\_ID\_FROM\_STEP\_2/index.html](http://storage.googleapis.com/chrome-browser-components/BUILD_ID_FROM_STEP_2/index.html)
 4.  Download the listed files and follow the steps in the README.
	# Checking out and building Chromium for Android

	There are instructions for other platforms linked from the
	[get the code](get_the_code.md) page.

	## Instructions for Google Employees

	Are you a Google employee? See
	[go/building-chrome](https://goto.google.com/building-chrome) instead.

	[TOC]

	## System requirements

	* A 64-bit Intel machine running Linux with at least 8GB of RAM. More
	than 16GB is highly recommended.
	* At least 100GB of free disk space.
	* You must have Git and Python installed already.

	Most development is done on Ubuntu. Other distros may or may not work;
	see the [Linux instructions](linux_build_instructions.md) for some suggestions.

	Building the Android client on Windows or Mac is not supported and doesn't work.

	## Install `depot_tools`

	Clone the `depot_tools` repository:

	```shell
	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`:

	```shell
	export PATH="$PATH:/path/to/depot_tools"
	```

	## Get the code

	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):

	```shell
	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:

	```shell
	cd src
	```

	### Converting an existing Linux checkout

	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`):

	```shell
	echo "target_os = [ 'android' ]" >> ../.gclient
	```

	Then run `gclient sync` to pull the new Android dependencies:

	```shell
	gclient sync
	```

	(This is the only difference between `fetch android` and `fetch chromium`.)

	### Install additional build dependencies

	Once you have checked out the code, run

	```shell
	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).

	### Run the hooks

	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:

	```shell
	gclient runhooks
	```

	Optional: You can also [install API
	keys](https://www.chromium.org/developers/how-tos/api-keys) if you want your
	build to talk to some Google services, but this is not necessary for most
	development and testing purposes.

	## Setting up the build

	Chromium uses [Ninja](https://ninja-build.org) as its main build tool along
	with a tool called [GN](../tools/gn/docs/quick_start.md) 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:

	```shell
	gn gen --args='target_os="android"' out/Default
	```

	* You only have to run this once for each new build directory, Ninja will
	update the build files as needed.
	* You can replace `Default` with another name, but
	it should be a subdirectory of `out`.
	* For other build arguments, including release settings, see [GN build
	configuration](https://www.chromium.org/developers/gn-build-configuration).
	The default will be a debug component build matching the current host
	operating system and CPU.
	* For more info on GN, run `gn help` on the command line or read the
	[quick start guide](../tools/gn/docs/quick_start.md).

	Also be aware that some scripts (e.g. `tombstones.py`, `adb_gdb.py`)
	require you to set `CHROMIUM_OUTPUT_DIR=out/Default`.

	## Build Chromium

	Build Chromium with Ninja using the command:

	```shell
	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`).

	## Installing and Running Chromium on a device

	Prepare the environment:

	```shell
	. build/android/envsetup.sh
	```

	### Plug in your Android device

	Make sure your Android device is plugged in via USB, and USB Debugging
	is enabled.

	To enable USB Debugging:

	* Navigate to Settings \> About Phone \> Build number
	* Click 'Build number' 7 times
	* Now navigate back to Settings \> Developer Options
	* Enable 'USB Debugging' and follow the prompts

	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:

	```shell
	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.

	### Build the full browser

	```shell
	ninja -C out/Default chrome_public_apk
	```

	And deploy it to your Android device:

	```shell
	out/Default/bin/chrome_public_apk install
	```

	The app will appear on the device as "Chromium".

	### Build Content shell

	Wraps the content module (but not the /chrome embedder). See
	[https://www.chromium.org/developers/content-module](https://www.chromium.org/developers/content-module)
	for details on the content module and content shell.

	```shell
	ninja -C out/Default content_shell_apk
	out/Default/bin/content_shell_apk install
	```

	this will build and install an Android apk under
	`out/Default/apks/ContentShell.apk`.

	### Build WebView

	[Android WebView](https://developer.android.com/reference/android/webkit/WebView.html)
	is a system framework component. Since Android KitKat, it is implemented using
	Chromium code (based off the [content module](https://dev.chromium.org/developers/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](https://www.chromium.org/developers/how-tos/build-instructions-android-webview)

	### Running

	For Content shell:

	```shell
	out/Default/bin/content_shell_apk launch [--args='--foo --bar'] http://example.com
	```

	For Chrome public:

	```shell
	out/Default/bin/chrome_public_apk launch [--args='--foo --bar'] http://example.com
	```

	### Logging and debugging

	Logging is often the easiest way to understand code flow. In C++ you can print
	log statements using the LOG macro. In Java, refer to
	[android_logging.md](android_logging.md).

	You can see these log via `adb logcat`, or:

	```shell
	out/Default/bin/chrome_public_apk logcat
	```

	To debug C++ code, use one of the following commands:

	```shell
	out/Default/bin/content_shell_apk gdb
	out/Default/bin/chrome_public_apk gdb
	```

	See [Android Debugging Instructions](android_debugging_instructions.md)
	for more on debugging, including how to debug Java code.

	### Testing

	For information on running tests, see [Android Test Instructions](android_test_instructions.md).

	### Faster Edit/Deploy

	"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.

	* Make sure to set` is_component_build = true `in your GN args
	* All apk targets have \*`_incremental` targets defined (e.g.
	`chrome_public_apk_incremental`) except for Webview and Monochrome

	Here's an example:

	```shell
	ninja -C out/Default chrome_public_apk_incremental
	out/Default/bin/chrome_public_apk install --incremental --verbose
	```

	For gunit tests (note that run_*_incremental automatically add
	`--fast-local-dev` when calling `test_runner.py`):

	```shell
	ninja -C out/Default base_unittests_incremental
	out/Default/bin/run_base_unittests_incremental
	```

	For instrumentation tests:

	```shell
	ninja -C out/Default chrome_public_test_apk_incremental
	out/Default/bin/run_chrome_public_test_apk_incremental
	```

	To uninstall:

	```shell
	out/Default/bin/chrome_public_apk uninstall
	```

	To avoid typing `_incremental` when building targets, you can use the GN arg:

	```
	incremental_apk_by_default = true
	```

	This will make `chrome_public_apk` build in incremental mode.


	## Tips, tricks, and troubleshooting

	### Rebuilding libchrome.so for a particular release

	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.

	1. Open Chrome on your Android device and visit chrome://version
	2. Copy down the id listed next to "Build ID:"
	3. Go to
	[http://storage.googleapis.com/chrome-browser-components/BUILD\_ID\_FROM\_STEP\_2/index.html](http://storage.googleapis.com/chrome-browser-components/BUILD_ID_FROM_STEP_2/index.html)
	4. Download the listed files and follow the steps in the README.