Windows: Ctrl + Alt + L
Linux: Ctrl + Shift + Alt + L
macOS: Option + Command + L
Reference: Key Commands and here are all of the commands for Windows/ Linux users and for Mac users.
As Rohit faced a problem in Ubuntu with the format code shortcut, this is due to the Ctrl + Alt + L key being used to lock the screen in Ubuntu.
I found that Ubuntu handles this keyboard shortcut first. So you should bind the Ctrl + Alt + L keyboard shortcut to something else so that it doesn't conflict with Ubuntu.
Steps
Go to System Tools → System Settings → Keyboard → Shortcuts tab → System → Lock Screen.
Select the row New Accelerator..., then press any special key with the Alpha key (e.g. Shift + L). You should've successfully changed the keyboard shortcut.
Check if the keyboard shortcut now works in Android Studio.
Alternative method
Ctrl + Alt + Shift + L (to show a dialog)
You can also use Eclipse shortcuts.
- Windows and Linux: Go to menu File → Settings → Keymap
- macOS: Go to menu Preferences → Keymap and choose Eclipse from the drop-down menu.
Using MenuBar
In Android studio 3.5, there is problem with rearranging the xml code, it also rearrange the views as well, so need to use these settings first.
Settings -> Editor -> Code Style -> XML-> Set From -> Predefined Style > Android.
Update for Android Studio 4+
Since Android Studio 4+, you might face issue shortcuts on mac. Shortcuts not working after updating to Android studio 4, in Mac? have an answer for that.
Updated to Android Studio 3.0
Please share missing items in comments.
A late answer but this alternative answer was not right for us ...
So, here's our gitignore file:
#built application files
*.apk
*.ap_
*.aab
# files for the dex VM
*.dex
# Java class files
*.class
# generated files
bin/
gen/
# Local configuration file (sdk path, etc)
local.properties
# Windows thumbnail db
Thumbs.db
# OSX files
.DS_Store
# Android Studio
*.iml
.idea
#.idea/workspace.xml - remove # and delete .idea if it better suit your needs.
.gradle
build/
.navigation
captures/
output.json
#NDK
obj/
.externalNativeBuild
Since Android Studio 2.2 and up to 3.0, new projects are created with this gitignore file:
*.iml
.gradle
/local.properties
/.idea/workspace.xml
/.idea/libraries
.DS_Store
/build
/captures
.externalNativeBuild
Deprecated - for older project format, add this section to your gitignore file:
/*/out
/*/*/build
/*/*/production
*.iws
*.ipr
*~
*.swp
This file should be located in the project's root folder and not inside the project's module folder.
Edit Notes:
Since version 0.3+ it seems you can commit and push *.iml and build.gradle files. If your project is based on Gradle: in the new open/import dialog, you should check the "use auto import"
checkbox and mark the "use default gradle wrapper (recommended)"
radio button. All paths are now relative as @George suggested.
Updated answer according to @128KB attached source and @Skela suggestions
Best Answer
Simple, right click on your project in Android Studio, then click on the Optimize Imports that should work.
Update
To do same thing which I described above, you can do same just pressing Ctrl+Alt+O, it will optimize imports of your current file and your entire project depends on your selection in a dialog.