page.title=Android Studio Tips and Tricks @jd:body
If you're unfamiliar with using Android Studio and the IntelliJ IDEA interface, this page provides some tips to help you get started with some of the most common tasks and productivity enhancements.
Android Studio includes a number of features to help you be more productive in your coding. This section notes a few of the key features to help you work quickly and efficiently.
With smart rendering, Android Studio displays links for quick fixes to rendering errors. For example, if you add a button to the layout without specifying the width and height attributes, Android Studio displays the rendering message Automatically add all missing attributes. Clicking the message adds the missing attributes to the layout.
While debugging, you can now right-click on bitmap variables in your app and invoke View Bitmap. This fetches the associated data from the debugged process and renders the bitmap in the debugger.
You can quickly add new code and resource files by clicking the appropriate directory in the
Project pane and pressing ALT + INSERT
on Windows and Linux or
COMMAND + N
on Mac. Based on the type of directory selected, Android Studio
offers to create the appropriate file type.
For example, if you select a layout directory, press ALT + INSERT
on Windows,
and select Layout resource file, a dialog opens so you can name the file
(you can exclude the {@code .xml} suffix) and choose a root view element. The editor then
switches to the layout design editor so you can begin designing your layout.
When checking build results, you can filter messages by message type to quickly locate messages of interest.
The activity parent can now be set in the Activity Wizard when creating a new activity. Setting a hierarchal parent sets the {@code Up} button to automatically appear in the app's Action bar when viewing a child activity, so the {@code Up} button no longer needs to be manually specified in the menu.xml file.
Android Studio offers an advanced layout editor that allows you to drag-and-drop widgets into your layout and preview your layout while editing the XML.
While editing in the Text view, you can preview the layout on devices by opening the Preview pane available on the right side of the window. Within the Preview pane, you can modify the preview by changing various options at the top of the pane, including the preview device, layout theme, platform version and more. To preview the layout on multiple devices simultaneously, select Preview All Screen Sizes from the device drop-down.
You can switch to the graphical editor by clicking Design at the bottom of the window. While editing in the Design view, you can show and hide the widgets available to drag-and-drop by clicking Palette on the left side of the window. Clicking Designer on the right side of the window reveals a panel with a layout hierarchy and a list of properties for each view in the layout.
Android Studio provides coding assistance for using annotations from the {@link android.support.annotation Support-Annotations} library, part of the Support Repository. Adding a dependency for this library enables you to decorate your code with annotations to help catch bugs, such as null pointer exceptions and resource type conflicts. You can also create enumerated annotations to, for example, check that a passed parameter value matches a value from a defined set of constants. For more information, see Improving Code Inspection with Annotations.
Android Studio allows you to look at what’s inside Java libraries when you don’t have access to the source code.
The decompiler is built into Android Studio for easy access. To use this feature, right-click a class, method, or field from a library for which you do not have source file access and select decompile.
The decompiled source code appears.To adjust the Java decompiler settings, select File > Settings > Other Settings > Java Decompiler.
Android Studio offers debugging and performance enhancements such as:
Choose Tools > New Scratch File to open a scratch file to quickly build and run code prototypes. Together with Android Studio coding assistance, scratch files allow you to quickly run and debug code updates with the support of all file operations. By embedding code created with scripting languages, you can run your code from within the scratch file.
Live templates allow you to enter code snippets for fast insertion and completion of small chunks of code. To insert a live template, type the template abbreviations and press the Tab key. Android Studio inserts the code snippet associated with the template into your code.
For example, entering the newInstance
abbreviation followed by the
Tab key inserts the code for a new fragment instance with argument placeholders.
public static $fragment$ newInstance($args$) { $nullChecks$ Bundle args = new Bundle(); $addArgs$ $fragment$ fragment = new $fragment$(); fragment.setArguments(args); return fragment; }
Similarly, the fbc
abbreviation inserts a findViewById
call along
with cast and resource id syntax.
() findViewById(R.id.);
Use the File > Settings > Editor > Live Templates menu option to display the full list of supported live templates and customize the inserted code.
This section list just a few of the code editing practices you should consider using when creating Android Studio apps.
For complete user documentation for the IntelliJ IDEA interface (upon which Android Studio is based), refer to the IntelliJ IDEA documentation.
For quick fixes to coding errors, the IntelliJ powered IDE implements the Alt + Enter key binding to fix errors (missing imports, variable assignments, missing references, etc) when possible, and if not, suggest the most probable solution.
The Ctrl + D key binding is great for quickly duplicating code lines or fragments. Simply select the desired line or fragment and enter this key binding.
In case you're not familiar with an API class, file or symbol, the Navigate menu lets you jump directly to the class of a method or field name without having to search through individual classes.
Scopes set the color of code segments for easy code identification and location. For example, you can set a scope to identify all code related to a specific action bar.
With language injection, the Android Studio IDE allows you to work with islands of different languages embedded in the source code. This extends the syntax, error highlighting and coding assistance to the embedded language. This can be especially useful for checking regular expression values inline, and validating XML and SQL statements.
This allows you to selectively hide and display sections of the code for readability. For example, resource expressions or code for a nested class can be folded or hidden in to one line to make the outer class structure easier to read. The inner class can be later expanded for updates.
When referencing images and icons in your code, a preview of the image or icon appears (in actual size at different densities) in the code margin to help you verify the image or icon reference. Pressing {@code F1} with the preview image or icon selected displays resource asset details, such as the dp settings.
You can now inspect theme attributes using View > Quick Documentation (F1), see the theme inheritance hierarchy, and resolve values for the various attributes.
If you invoke View > Quick Documentation (usually bound to F1) on the theme attribute ?android:textAppearanceLarge, you will see the theme inheritance hierarchy and resolved values for the various attributes that are pulled in.
The following tables list keyboard shortcuts for common operations.
Note: This section lists Android Studio keyboard shortcuts for the default keymap. To change the default keymap on Windows and Linux, go to File > Settings > Keymap. If you're using Mac OS X, update your keymap to use the Mac OS X 10.5+ version keymaps under Android Studio > Preferences > Keymap.
Action | Android Studio Key Command |
---|---|
Command look-up (autocomplete command name) | CTRL + SHIFT + A |
Project quick fix | ALT + ENTER |
Reformat code | CTRL + ALT + L (Win) OPTION + CMD + L (Mac) |
Show docs for selected API | CTRL + Q (Win) F1 (Mac) |
Show parameters for selected method | CTRL + P |
Generate method | ALT + Insert (Win) CMD + N (Mac) |
Jump to source | F4 (Win) CMD + down-arrow (Mac) |
Delete line | CTRL + Y (Win) CMD + Backspace (Mac) |
Search by symbol name | CTRL + ALT + SHIFT + N (Win) OPTION + CMD + O (Mac) |
Action | Android Studio Key Command |
---|---|
Build | CTRL + F9 (Win) CMD + F9 (Mac) |
Build and run | SHIFT + F10 (Win) CTRL + R (Mac) |
Toggle project visibility | ALT + 1 (Win) CMD + 1 (Mac) |
Navigate open tabs | ALT + left-arrow; ALT + right-arrow (Win) CTRL + left-arrow; CTRL + right-arrow (Mac) |
For a complete keymap reference guide, see the IntelliJ IDEA documentation.