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

 # Android Build Instructions

 **See also [the old version of this page](old_android_build_instructions.md).**

 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:

     $ 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

 ## 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):

     $ 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 directory called `src`.
 The remaining instructions assume you are now in that directory:

     $ 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):

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

 Then run gclient sync to pull the new Android dependencies:

     gclient sync

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

 ### Install additional build dependencies

 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 builds 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:

     $ gclient runhooks

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

 ### Configure the JDK

 Make also sure that OpenJDK 1.7 is selected as default:

 `sudo update-alternatives --config javac`
 `sudo update-alternatives --config java`
 `sudo update-alternatives --config javaws`
 `sudo update-alternatives --config javap`
 `sudo update-alternatives --config jar`
 `sudo update-alternatives --config jarsigner`

 ## Setting up the Build

 Chromium uses [Ninja](https://ninja-build.org) as its main build tool, and
 a tool called [GN](../tools/gn/docs/quick_start.md) to generate
 the .ninja files to do the build. To create a build directory configured
 to build Android, run:

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

 * You only have to do run this command once, it will self-update the build
   files as needed after that.
 * You can replace `out/Default` with another directory name, but we recommend
   it should still be a subdirectory of `out`.
 * To specify build parameters for GN builds, 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:

     $ 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 to Ninja
 the GN label 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

 If the `adb_install_apk.py` script below fails, make sure aapt is in
 your PATH. If not, add aapt's path to your PATH environment variable (it
 should be
 `/path/to/src/third_party/android_tools/sdk/build-tools/{latest_version}/`).

 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/Release chrome_public_apk
 ```

 And deploy it to your Android device:

 ```shell
 CHROMIUM_OUTPUT_DIR=$gndir build/android/adb_install_apk.py $gndir/apks/ChromePublic.apk # for gn.
 ```

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

 ### Build Content shell

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

 ```shell
 ninja -C out/Release content_shell_apk
 build/android/adb_install_apk.py out/Release/apks/ContentShell.apk
 ```

 this will build and install an Android apk under
 `out/Release/apks/ContentShell.apk`. (Where `Release` is the name of your build
 directory.)

 If you use custom out dir instead of standard out/ dir, use
 CHROMIUM_OUT_DIR env.

 ```shell
 export CHROMIUM_OUT_DIR=out_android
 ```

 ### Build WebView shell

 [Android WebView](http://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](http://dev.chromium.org/developers/content-module)).
 It is possible to test modifications to WebView using a simple test shell. The
 WebView shell is a view with a URL bar at the top (see [code](https://code.google.com/p/chromium/codesearch#chromium/src/android_webview/test/shell/src/org/chromium/android_webview/test/AwTestContainerView.java))
 and is **independent** of the WebView **implementation in the Android system** (
 the WebView shell is essentially a standalone unbundled app).
 As drawback, the shell runs in non-production rendering mode only.

 ```shell
 ninja -C out/Release android_webview_apk
 build/android/adb_install_apk.py out/Release/apks/AndroidWebView.apk
 ```

 If, instead, you want to build the complete Android WebView framework component and test the effect of your chromium changes in other Android app using the WebView, you should follow the [Android AOSP + chromium WebView instructions](http://www.chromium.org/developers/how-tos/build-instructions-android-webview)

 ### Running

 Set [command line flags](https://www.chromium.org/developers/how-tos/run-chromium-with-flags) if necessary.

 For Content shell:

 ```shell
 build/android/adb_run_content_shell  http://example.com
 ```

 For Chrome public:

 ```shell
 build/android/adb_run_chrome_public  http://example.com
 ```

 For Android WebView shell:

 ```shell
 build/android/adb_run_android_webview_shell 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 or printf(). In Java, you can print log
 statements using [android.util.Log](http://developer.android.com/reference/android/util/Log.html):

 `Log.d("sometag", "Reticulating splines progress = " + progress);`

 You can see these log statements using adb logcat:

 ```shell
 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:

 ```shell
 build/android/adb_gdb_content_shell
 build/android/adb_gdb_chrome_public
 build/android/adb_gdb_android_webview_shell http://example.com
 ```

 See [Debugging Chromium on Android](https://www.chromium.org/developers/how-tos/debugging-on-android)
 for more on debugging, including how to debug Java code.

 ### Testing

 For information on running tests, see [android\_test\_instructions.md](https://chromium.googlesource.com/chromium/src/+/master/docs/android_test_instructions.md).

 ### Faster Edit/Deploy (GN only)

 GN's "incremental install" uses reflection and side-loading to speed up the edit
 & deploy cycle (normally < 10 seconds).

 *   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`)

 Here's an example:

 ```shell
 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):

 ```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/install_chrome_public_apk_incremental -v --uninstall
 ```

 ## 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.
	# Android Build Instructions

	See also [the old version of this page](old_android_build_instructions.md).

	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:

	$ 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

	## 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):

	$ 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 directory called `src`.
	The remaining instructions assume you are now in that directory:

	$ 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):

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

	Then run gclient sync to pull the new Android dependencies:

	gclient sync

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

	### Install additional build dependencies

	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 builds 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:

	$ gclient runhooks

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

	### Configure the JDK

	Make also sure that OpenJDK 1.7 is selected as default:

	`sudo update-alternatives --config javac`
	`sudo update-alternatives --config java`
	`sudo update-alternatives --config javaws`
	`sudo update-alternatives --config javap`
	`sudo update-alternatives --config jar`
	`sudo update-alternatives --config jarsigner`

	## Setting up the Build

	Chromium uses [Ninja](https://ninja-build.org) as its main build tool, and
	a tool called [GN](../tools/gn/docs/quick_start.md) to generate
	the .ninja files to do the build. To create a build directory configured
	to build Android, run:

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

	* You only have to do run this command once, it will self-update the build
	files as needed after that.
	* You can replace `out/Default` with another directory name, but we recommend
	it should still be a subdirectory of `out`.
	* To specify build parameters for GN builds, 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:

	$ 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 to Ninja
	the GN label 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

	If the `adb_install_apk.py` script below fails, make sure aapt is in
	your PATH. If not, add aapt's path to your PATH environment variable (it
	should be
	`/path/to/src/third_party/android_tools/sdk/build-tools/{latest_version}/`).

	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/Release chrome_public_apk
	```

	And deploy it to your Android device:

	```shell
	CHROMIUM_OUTPUT_DIR=$gndir build/android/adb_install_apk.py $gndir/apks/ChromePublic.apk # for gn.
	```

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

	### Build Content shell

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

	```shell
	ninja -C out/Release content_shell_apk
	build/android/adb_install_apk.py out/Release/apks/ContentShell.apk
	```

	this will build and install an Android apk under
	`out/Release/apks/ContentShell.apk`. (Where `Release` is the name of your build
	directory.)

	If you use custom out dir instead of standard out/ dir, use
	CHROMIUM_OUT_DIR env.

	```shell
	export CHROMIUM_OUT_DIR=out_android
	```

	### Build WebView shell

	[Android WebView](http://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](http://dev.chromium.org/developers/content-module)).
	It is possible to test modifications to WebView using a simple test shell. The
	WebView shell is a view with a URL bar at the top (see [code](https://code.google.com/p/chromium/codesearch#chromium/src/android_webview/test/shell/src/org/chromium/android_webview/test/AwTestContainerView.java))
	and is independent of the WebView implementation in the Android system (
	the WebView shell is essentially a standalone unbundled app).
	As drawback, the shell runs in non-production rendering mode only.

	```shell
	ninja -C out/Release android_webview_apk
	build/android/adb_install_apk.py out/Release/apks/AndroidWebView.apk
	```

	If, instead, you want to build the complete Android WebView framework component and test the effect of your chromium changes in other Android app using the WebView, you should follow the [Android AOSP + chromium WebView instructions](http://www.chromium.org/developers/how-tos/build-instructions-android-webview)

	### Running

	Set [command line flags](https://www.chromium.org/developers/how-tos/run-chromium-with-flags) if necessary.

	For Content shell:

	```shell
	build/android/adb_run_content_shell http://example.com
	```

	For Chrome public:

	```shell
	build/android/adb_run_chrome_public http://example.com
	```

	For Android WebView shell:

	```shell
	build/android/adb_run_android_webview_shell 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 or printf(). In Java, you can print log
	statements using [android.util.Log](http://developer.android.com/reference/android/util/Log.html):

	`Log.d("sometag", "Reticulating splines progress = " + progress);`

	You can see these log statements using adb logcat:

	```shell
	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:

	```shell
	build/android/adb_gdb_content_shell
	build/android/adb_gdb_chrome_public
	build/android/adb_gdb_android_webview_shell http://example.com
	```

	See [Debugging Chromium on Android](https://www.chromium.org/developers/how-tos/debugging-on-android)
	for more on debugging, including how to debug Java code.

	### Testing

	For information on running tests, see [android\_test\_instructions.md](https://chromium.googlesource.com/chromium/src/+/master/docs/android_test_instructions.md).

	### Faster Edit/Deploy (GN only)

	GN's "incremental install" uses reflection and side-loading to speed up the edit
	& deploy cycle (normally < 10 seconds).

	* 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`)

	Here's an example:

	```shell
	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):

	```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/install_chrome_public_apk_incremental -v --uninstall
	```

	## 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.