| # Android Studio | |
| [TOC] | |
| ## Usage | |
| Make sure you have followed | |
| [android build instructions](android_build_instructions.md) already. | |
| ```shell | |
| build/android/gradle/generate_gradle.py --output-directory out/Debug | |
| ``` | |
| The above commands create a project dir `gradle` under your output directory. | |
| Use `--project-dir <project-dir>` to change this. | |
| To import the project: | |
| * Use "Import Project", and select the directory containing the generated | |
| project, e.g. `out/Debug/gradle`. | |
| See [android_test_instructions.md](testing/android_test_instructions.md#Using-Emulators) | |
| for more information about building and running emulators. | |
| Feel free to accept Android Studio's recommended actions. `generate_gradle.py` | |
| should have already set up a working version of the gradle wrapper and the | |
| android gradle plugin, as well as a default Android SDK location at | |
| `~/Android/Sdk`. Since the same script needs to support various versions of | |
| Android Studio, the defaults may have lower version than the one recommended by | |
| your version of Android Studio. After you accept Android Studio's update actions | |
| the `generate_gradle.py` script will try to keep the newer versions when it is | |
| re-run. | |
| You'll need to re-run `generate_gradle.py` whenever new directories containing | |
| source files are added. | |
| * After regenerating, Android Studio should prompt you to "Sync". If it | |
| doesn't, try some of the following options: | |
| * File -> "Sync Project with Gradle Files" | |
| * Button with two arrows on the right side of the top strip. | |
| * Help -> Find Action -> "Sync Project with Gradle Files" | |
| * After `gn clean` you may need to restart Android Studio. | |
| * File -> "Invalidate Caches / Restart..." | |
| ## How It Works | |
| By default, only an `_all` module containing all java apk targets is generated. | |
| If just one apk target is explicitly specified, then a single apk module is | |
| generated. | |
| If you really prefer a more detailed structure of gn targets, the deprecated | |
| `--split-projects` flag can be used. This will generate one module for every gn | |
| target in the dependency graph. This can be very slow and is no longer | |
| supported. | |
| ### Generated files | |
| Most generated .java files in GN are stored as `.srcjars`. Android Studio does | |
| not support them. Our build will automatically extract them to a | |
| `generated_java` directory in the output directory during the build. Thus if a | |
| generated file is missing in Android Studio, build it with ninja first and it | |
| should show up in Android Studio afterwards. | |
| ### Native Files | |
| This option is deprecated and no longer supported since Android Studio is very | |
| slow when editing in a code base with a large number of C++ files, and Chromium | |
| has a lot of C++ code. It is recommended to use [VS Code](vscode.md) to edit | |
| native files and stick to just editing java files in Android Studio. | |
| If you still want to enable editing native C/C++ files with Android Studio, pass | |
| in any number of `--native-target [target name]` flags in order to use it. The | |
| target must be the full path and name of a valid gn target (no short-forms). | |
| This will require you to install `cmake` and `ndk` when prompted. Accept Android | |
| Studio's prompts for these SDK packages. | |
| You need to disable a new gradle option in order to edit native files: | |
| File -> Settings -> Experimental | |
| -> Gradle and uncheck "Only resolve selected variants". | |
| This is not necessary, but to avoid "This file is not part of the project...", | |
| you can either add an extra `--native-target` flag or simply copy and paste the | |
| absolute path to that file into the CMakeLists.txt file alongside the existing | |
| file paths. Note that changes to CMakeLists.txt will be overwritten on your next | |
| invocation of `generate_gradle.py`. | |
| Example: | |
| ```shell | |
| build/android/gradle/generate_gradle.py --native-target //chrome/android:libchrome | |
| ``` | |
| ## Tips | |
| * Use environment variables to avoid having to specify `--output-directory`. | |
| * Example: Append `export CHROMIUM_OUT_DIR=out; export BUILDTYPE=Debug` to | |
| your `~/.bashrc` to always default to `out/Debug`. | |
| * Using the Java debugger is documented | |
| [here](android_debugging_instructions.md#android-studio). | |
| * Configuration instructions can be found | |
| [here](http://tools.android.com/tech-docs/configuration). One suggestions: | |
| * Launch it with more RAM: | |
| `STUDIO_VM_OPTIONS=-Xmx2048m /opt/android-studio-stable/bin/studio-launcher.sh` | |
| * If you ever need to reset it: `rm -r ~/.config/Google/AndroidStudio*/` | |
| * Import Chromium-specific style and inspections settings: | |
| * Help -> Find Action -> "Code Style" (settings) -> Java -> | |
| Scheme -> Import Scheme | |
| * Select `tools/android/android_studio/ChromiumStyle.xml` -> OK | |
| * Help -> Find Action -> "Inspections" (settings) -> | |
| Profile -> Import profile | |
| * Select `tools/android/android_studio/ChromiumInspections.xml` -> OK | |
| * Turn on automatic import: | |
| * Help -> Find Action -> "Auto Import" | |
| * Tick all the boxes under "Java" and change the dropdown to "All". | |
| * Turn on documentation on mouse hover: | |
| * Help -> Find Action -> "Show quick documentation on mouse move" | |
| * Turn on line numbers: | |
| * Help -> Find Action -> "Show line numbers" | |
| * Turn off indent notification: | |
| * Help -> Find Action -> "Show notifications about detected indents" | |
| * Format changed files (Useful for changes made by running code inspection): | |
| * Set up version control | |
| * File -> Settings -> Version Control | |
| * Add src directories | |
| * Commit changes and reformat | |
| * Help -> Find Action -> "Commit Changes" | |
| * Check "Reformat code" & "Optimize imports" and commit | |
| * Change theme from GTK+ to another one to avoid invisible menus. | |
| * Help -> Find Action -> "Theme: Settings > Appearance" | |
| ### Useful Shortcuts | |
| * `Shift - Shift`: Search to open file or perform IDE action | |
| * `Ctrl + N`: Jump to class | |
| * `Ctrl + Shift + T`: Jump to test | |
| * `Ctrl + Shift + N`: Jump to file | |
| * `Ctrl + F12`: Jump to method | |
| * `Ctrl + G`: Jump to line | |
| * `Shift + F6`: Rename variable | |
| * `Ctrl + Alt + O`: Organize imports | |
| * `Alt + Enter`: Quick Fix (use on underlined errors) | |
| * `F2`: Find next error | |
| ### Building with Gradle | |
| Gradle builds are not supported. Only editing is supported in Android Studio. | |
| Use ninja to build as usual. | |
| ## Status | |
| ### What works | |
| * Android Studio v2021~v2023. | |
| * Java editing. | |
| * Application code in `main` sourceset. | |
| * Instrumentation test code in `androidTest` sourceset. | |
| * Native code editing (deprecated, use [VS Code](vscode.md) instead). | |
| * Symlinks to existing .so files in jniLibs (doesn't generate them). | |
| * Editing resource xml files | |
| * Layout editor (limited functionality). | |
| * Java debugging (see | |
| [here](/docs/android_debugging_instructions.md#Android-Studio)). | |
| * Import resolution and refactoring across java files. | |
| * Separate Android SDK for Android Studio. | |
| ### What doesn't work | |
| * Building with Gradle. | |
| * The "Make Project" button doesn't work. | |
| * Stick to using `autoninja` to build targets and just use Android Studio | |
| for editing java source files. | |
| * No active work is underway or planned to expand Android Studio support. |