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page.title=Android Studio Tips and Tricks
@jd:body

<div id="qv-wrapper">
<div id="qv">

    <h2>In this document</h2>
    <ol>
      <li><a href="#productivity-features">Productivity Shortcuts</a></li>
      <li><a href="#intellij">Working with IntelliJ</a></li>
      <li><a href="#key-commands">Key Commands</a></li>
    </ol>

  <h2>See also</h2>
  <ol>
    <li><a href="{@docRoot}sdk/index.html">Download Android Studio</a></li>
    <li><a href="http://wiki.jetbrains.net/intellij/Android">IntelliJ IDEA Android Tutorials</a></li>
    <li><a href="http://confluence.jetbrains.com/display/IntelliJIDEA/FAQ+on+Migrating+to+IntelliJ+IDEA">IntelliJ FAQ on migrating to IntelliJ IDEA</a></li>
  </ol>

</div>
</div>

<p>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. </p>


<h2 id="productivity-features">Productivity Shortcuts</h2>

<p>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.
</p>


<h3>Smart Rendering</h3>
<p>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 <em>width</em> and
<em>height</em> attributes, Android Studio displays the rendering message <em>Automatically
add all missing attributes</em>. Clicking the message adds the missing attributes to the layout.</p>


<h3> Bitmap rendering in the debugger</h3>
<p>While debugging, you can now right-click on bitmap variables in your app and invoke
<em>View Bitmap</em>. This fetches the associated data from the debugged process and renders
the bitmap in the debugger. </p>
<p><img src="{@docRoot}images/tools/studio-bitmap-rendering.png" style="width:350px"/></p>
<p class="img-caption"><strong>Figure 1.</strong> Bitmap Rendering</p>


<h3>Creating new files</h3>
<p>You can quickly add new code and resource files by clicking the appropriate directory in the
<strong>Project</strong> pane and pressing <code>ALT + INSERT</code> on Windows and Linux or
<code>COMMAND + N</code> on Mac. Based on the type of directory selected, Android Studio
offers to create the appropriate file type.</p>

<p>For example, if you select a layout directory, press <code>ALT + INSERT</code> on Windows,
and select <strong>Layout resource file</strong>, 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.</p>


<h3>Output window message filtering</h3>
<p>When checking build results, you can filter messages by <em>message type</em> to quickly
locate messages of interest.</p>
<img src="{@docRoot}images/tools/studio-outputwindowmsgfiltering.png" style="width:200px"style="width:200px" />
<p class="img-caption"><strong>Figure 2.</strong> Filter Build Messages</p>


<h3>Hierarchical parent setting</h3>
<p>The activity parent can now be set in the Activity Wizard when creating a new
activity. Setting a <em>hierarchal parent</em> 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 <em>menu.xml</em> file.</p>


<h3>Creating layouts</h3>
<p>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.</p>

<p>While editing in the <strong>Text</strong> view, you can preview the layout on devices by
opening the <strong>Preview</strong> 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 <strong>Preview All Screen Sizes</strong> from the
device drop-down.</p>
<p><img src="{@docRoot}images/tools/studio-previewall.png" style="width:350px"/></p>
<p class="img-caption"><strong>Figure 3.</strong> Preview All Screens</p>

<p>You can switch to the graphical editor by clicking <strong>Design</strong> 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 <strong>Palette</strong> on the left side of the
window. Clicking <strong>Designer</strong> 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.</p>


<h3>Annotations</h3>
<p>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
<a href="{@docRoot}tools/debugging/annotations.html#annotations">Improving Code Inspection with
Annotations</a>.
</p>


<h3>Java class decompiling</h3>
<p>Android Studio allows you to look at what’s inside Java libraries when you don’t have access
to the source code. </p>

<p>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
<strong>decompile</strong>.</p> The decompiled source code appears. </p>

<p>To adjust the Java decompiler settings, select
<strong>File > Settings > Other Settings > Java Decompiler</strong>. </p>


<h3>Debugging and performance enhancements</h3>
<p>Android Studio offers debugging and performance enhancements such as:</p>
<ul>
  <li>Custom keymaps. To modify the current keymap, choose
   <strong>File &gt; Settings &gt; Keymap</strong>.  </li>
  <li>Support for high density (Retina) displays on Windows and Linux.  </li>
  <li>Scratch files for quick prototyping without creating any project files.
   <p>Choose <strong>Tools &gt; New Scratch File</strong> 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.</p>
  </li>
</ul>


<h3 id="live-template">Live templates</h3>
<p>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. </p>

<p>For example, entering the <code>newInstance</code> abbreviation followed by the
Tab key inserts the code for a new fragment instance with argument placeholders. </p>

<pre>
public static $fragment$ newInstance($args$) {
    $nullChecks$
    Bundle args = new Bundle();
    $addArgs$
    $fragment$ fragment = new $fragment$();
    fragment.setArguments(args);
    return fragment;
}
</pre>

<p>Similarly, the <code>fbc</code> abbreviation inserts a <code>findViewById</code> call along
with cast and resource id syntax. </p>

<pre>
() findViewById(R.id.);
</pre>

<p>Use the <strong>File &gt; Settings &gt; Editor &gt; Live Templates</strong> menu option to
display the full list of supported live templates and customize the inserted code.  </p>



<h2 id="intellij">Working with IntelliJ-based Coding Practices</h3>

<p>This section list just a few of the code editing
practices you should consider using when creating Android Studio apps. </p>

<p>For complete user documentation for the IntelliJ IDEA interface (upon which Android Studio
is based), refer to the
<a href="http://www.jetbrains.com/idea/documentation/index.jsp">IntelliJ IDEA documentation</a>.</p>


<h3><em>Alt + Enter</em> key binding</h3>
<p>For quick fixes to coding errors, the IntelliJ powered IDE implements the <em>Alt + Enter</em>
key binding to fix errors (missing imports, variable assignments, missing references, etc) when
possible, and if not, suggest the most probable solution. </p>


<h3><em>Ctrl + D</em> key binding</h3>
<p>The <em>Ctrl + D</em> key binding is great for quickly duplicating code lines or fragments.
Simply select the desired line or fragment and enter this key binding. </p>


<h3>Navigate menu</h3>
<p>In case you're not familiar with an API class, file or symbol, the <em>Navigate</em> menu lets
you jump directly to the class of a method or field name without having to search through
individual classes. </p>


<h3>Inspection scopes</h3>
<p>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.   </p>


<h3>Injecting languages</h3>
<p>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.</p>


<h3>Code folding</h3>
<p>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. </p>


<h3>Image and color preview</h3>
<p>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 <em>dp</em> settings.   </p>


<h3>Quick F1 documentation</h3>
<p>You can now inspect theme attributes using <strong>View > Quick Documentation</strong>
(<strong>F1</strong>),
see the theme inheritance hierarchy, and resolve values for the various attributes.</p>

<p>If you invoke <strong> View > Quick Documentation</strong> (usually bound to F1) on the theme
attribute <em>?android:textAppearanceLarge</em>, you will see the theme inheritance hierarchy and
resolved values for the various attributes that are pulled in.</p>



<h3 id="key-commands">Keyboard Commands</h3>

<p>The following tables list keyboard shortcuts for common operations.</p>

<p class="note"><strong>Note:</strong> This section lists Android Studio keyboard shortcuts
for the default keymap. To change the default keymap on Windows and Linux, go to
<strong>File</strong> &gt; <strong>Settings</strong> &gt; <strong>Keymap</strong>. If you're
using Mac OS X, update your keymap to use the Mac OS X 10.5+ version keymaps under
<strong>Android Studio > Preferences > Keymap</strong>.</p>


<p class="table-caption"><strong>Table 1.</strong> Programming key commands</p>
<table>
<tr><th>Action</th><th>Android Studio Key Command</th></tr>

<tr>
  <td>Command look-up (autocomplete command name)</td>
  <td>CTRL + SHIFT + A</td>
</tr>

<tr>
  <td>Project quick fix</td>
  <td>ALT + ENTER</td>
</tr>

<tr>
  <td>Reformat code</td>
  <td>CTRL + ALT + L (Win)<br>
      OPTION + CMD + L (Mac)</td>
</tr>

<tr>
  <td>Show docs for selected API</td>
  <td>CTRL + Q (Win)<br>
      F1 (Mac)</td>
</tr>

<tr>
  <td>Show parameters for selected method</td>
  <td>CTRL + P</td>
</tr>

<tr>
  <td>Generate method</td>
  <td>ALT + Insert (Win)<br>
      CMD + N (Mac)</td>
</tr>

<tr>
  <td>Jump to source</td>
  <td>F4 (Win)<br>
      CMD + down-arrow (Mac)</td>
</tr>

<tr>
  <td>Delete line</td>
  <td>CTRL + Y (Win)<br>
      CMD + Backspace (Mac)</td>
</tr>

<tr>
  <td>Search by symbol name</td>
  <td>CTRL + ALT + SHIFT + N (Win)<br>
      OPTION + CMD + O (Mac)</td>
</tr>

</table>




<p class="table-caption"><strong>Table 2.</strong> Project and editor key commands</p>
<table>
<tr><th>Action</th><th>Android Studio Key Command</th></tr>

<tr>
  <td>Build</td>
  <td>CTRL + F9 (Win)<br>
      CMD + F9 (Mac)</td>
</tr>

<tr>
  <td>Build and run</td>
  <td>SHIFT + F10 (Win)<br>
      CTRL + R (Mac)</td>
</tr>

<tr>
  <td>Toggle project visibility</td>
  <td>ALT + 1 (Win)<br>
      CMD + 1 (Mac)</td>
</tr>

<tr>
  <td>Navigate open tabs</td>
  <td>ALT + left-arrow; ALT + right-arrow (Win)<br>
      CTRL + left-arrow; CTRL + right-arrow (Mac)</td>
</tr>

</table>

<p>For a complete keymap reference guide, see the
<a href="http://www.jetbrains.com/idea/documentation/index.jsp">IntelliJ IDEA</a>
documentation.</p>