versions/nougat/android-7.0-changes.jd

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@jd:body


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

<h2>  </h2>

<ol>
  <li><a href="#perf"> </a>
    <ol>
      <li><a href="#doze"> </a></li>
      <li><a href="#bg-opt"> </a></li>
    </ol>
  </li>
  <li><a href="#perm"> </a>
  </li>
  <li><a href="#sharing-files">   </a></li>
  <li><a href="#accessibility"> </a>
    <ol>
      <li><a href="#screen-zoom"> /</a></li>
      <li><a href="#vision-settings">  Vision Settings</a></li>
    </ol>
  </li>
  <li><a href="#ndk">   NDK </a></li>
  <li><a href="#afw">Android for Work</a></li>
  <li><a href="#annotations"> </a></li>
  <li><a href="#other">  </a></li>
</ol>

<h2> </h2>
<ol>
  <li><a href="{@docRoot}preview/api-overview.html">
    Android N API </a></li>
</ol>

</div>
</div>


<p>
  Android N
     API     .

   .
</p>

<p>
   Android     ,
          .
</p>


<h2 id="perf"> </h2>

<p>
Android N     RAM
    .   ,
     ,
     .
</p>

<h3 id="doze"> </h3>

<p>
  Android 6.0(API  23)
        CPU
      . Android N

CPU
 ,     (:      ).
</p>


<img src="{@docRoot}images/android-7.0/doze-diagram-1.png" alt="" height="251px" id="figure1" />
<p class="img-caption">
  <strong> 1.</strong>
   .
</p>

<p>

         .
  ,   .
       ,       {@link android.os.PowerManager.WakeLock},
{@link android.app.AlarmManager} , GPS  Wi-Fi
.
      ,
        ,
     / .
</p>


<img src="{@docRoot}images/android-7.0/doze-diagram-2.png" alt="" id="figure2" />
<p class="img-caption">
  <strong> 2.</strong>
           .
</p>

<p>

    . <a href="{@docRoot}training/monitoring-device-state/doze-standby.html">
 </a>  , Android 6.0(API  23)


   .
     .  , GCM(Google Cloud Messaging)

 .
</p>


<h3 id="bg-opt">Project Svelte:  </h3>

<p>
  Android N
     .
,
     .
   .
</p>

<p>
        (: Wi-Fi
     ).
 {@link
 android.net.ConnectivityManager#CONNECTIVITY_ACTION}
        .
  ,
     .
</p>

<p>
  ,   Android   (: )  {@link
 android.hardware.Camera#ACTION_NEW_PICTURE}  {@link
 android.hardware.Camera#ACTION_NEW_VIDEO}
   .     ,
 .
</p>

<p>
     , Android N
 .
</p>

<ul>
  <li>Android N           {@link
 android.net.ConnectivityManager#CONNECTIVITY_ACTION}
 .
 {@link android.content.BroadcastReceiver}
   {@code CONNECTIVITY_CHANGE}   .
  </li>

  <li> {@link
 android.hardware.Camera#ACTION_NEW_PICTURE}  {@link
 android.hardware.Camera#ACTION_NEW_VIDEO}    .   Android N
       .
  </li>
</ul>

<p>      ,
 Android N              .
  Android
       .  , {@link
 android.app.job.JobScheduler} API  (:
   )
  .  {@link
 android.app.job.JobScheduler}        .
</p>

<p>
  N
 <a href="{@docRoot}preview/features/background-optimization.html"> </a>
 .
</p>

<h2 id="perm"> </h2>

<p>
  Android N         .
</p>

<h3 id="permfilesys">   </h3>

<p>
      , Android N
   (<code>0700</code>).

       .       .
</p>

<ul>
  <li>

    ,
{@link android.content.Context#MODE_WORLD_READABLE} /
{@link android.content.Context#MODE_WORLD_WRITEABLE}
{@link java.lang.SecurityException} .
    <p class="note">
      <strong>:</strong>      .

API  {@link java.io.File File} API        .
          .
    </p>
  </li>
  <li>
       <code>file://</code> URI
    .
<code>file://</code> URI
<code>FileUriExposedException</code> .
  {@link
 android.support.v4.content.FileProvider}  .
  </li>
  <li>
    {@link android.app.DownloadManager}
        .   {@link
 android.app.DownloadManager#COLUMN_LOCAL_FILENAME}
     . Android N
   {@link android.app.DownloadManager#COLUMN_LOCAL_FILENAME}   {@link java.lang.SecurityException}
.


{@link
 android.app.DownloadManager.Request#setDestinationInExternalFilesDir
 DownloadManager.Request.setDestinationInExternalFilesDir()}
 {@link
 android.app.DownloadManager.Request#setDestinationInExternalPublicDir
 DownloadManager.Request.setDestinationInExternalPublicDir()}


{@link android.app.DownloadManager#COLUMN_LOCAL_FILENAME}      ,
        . {@link android.app.DownloadManager}

{@link android.content.ContentResolver#openFileDescriptor
 ContentResolver.openFileDescriptor()}  .
  </li>
</ul>

<h2 id="sharing-files">   </h2>

<p>
Android N    , Android    {@code file://} URI
 {@link android.os.StrictMode} API
.  URI
{@code FileUriExposedException}     .
</p>

<p>
    {@code content://} URI
  URI      .
{@link android.support.v4.content.FileProvider}   .

 <a href="{@docRoot}training/secure-file-sharing/index.html"> </a> .
</p>

<h2 id="accessibility"> </h2>

<p>
  Android N
       .
     ,

   .
</p>


<h3 id="screen-zoom"> /</h3>

<p>
  Android N  <strong>Display size</strong>
,         ,
    .    <a href="http://developer.android.com/guide/topics/resources/providing-resources.html">sw320dp</a>    /
  ,       Nexus 4
 .
</p>

<div class="cols">

<div class="col-6">
  <img src="{@docRoot}images/android-7.0/screen-zoom-1.png" alt="" height="XXX" id="figure1" />
</div>
<div class="col-6">
  <img src="{@docRoot}images/android-7.0/screen-zoom-2.png" alt="" height="XXX" id="figure1" />
</div>

</div> <!-- end cols -->
<p class="img-caption">
  <strong> 3.</strong>   Android N
   Display size    .
</p>


<p>

  .
</p>

<ul>
  <li> API  23
    . ,
   <em>Settings</em>
  <strong>Display size</strong>  ,
     .
  , <a href="{@docRoot}guide/topics/resources/runtime-changes.html">  </a>  ,

      .
  </li>

  <li> Android N   ,
<a href="{@docRoot}guide/topics/resources/runtime-changes.html">  </a>
,    (  )
.
  </li>
</ul>

<p>
   Android    ,
       .     .
</p>

<ul>
  <li>  <code><a href=
  "{@docRoot}guide/topics/resources/providing-resources.html">sw320dp</a></code>
 .
  </li>

  <li>   ,
(:      )
.
  .
    <p class="note">
      <strong>:</strong>     ,

   .    ,

   .
    </p>
  </li>

  <li>
  ,     .  , <a href="{@docRoot}guide/practices/screens_support.html">  </a>(<code>dp</code>)
  .
  </li>
</ul>

<h3 id="vision-settings">  Vision Settings</h3>

<p>
  Android N Welcome  Vision Settings
,
  <strong>Magnification gesture</strong>, <strong>Font size</strong>,
<strong>Display size</strong>  <strong>TalkBack</strong>       .
       .    ,

  .   <strong>Settings &gt;
  Accessibility</strong>  .
</p>

<h2 id="ndk">   NDK </h2>

<p>
   API     Android N    .
  NDK   Android
  API  . Android      API
 .
</p>

<p>
   API    , Android N
      API   logcat   .
  ,
      .
   API   ,
      .
</p>

<p>
      ,  API
  API      NDK  .
  ,
    ,
 (: <code>libpng</code>) NDK     .
  .so  APK   .
</p>

<p class="caution">
  <strong>:</strong>     API
   .     , Android
           .
</p>

<p>
   NDK
    .
 Android        . OpenSSL BoringSSL     .
  , NDK
      ,
    .     NDK
Android API    .
</p>

<p>
         ,
 Android N       Java  NDK     .
</p>

<p>Java  :</p>
<pre class="no-pretty-print">
java.lang.UnsatisfiedLinkError: dlopen failed: library "/system/lib/libcutils.so"
    is not accessible for the namespace "classloader-namespace"
</pre>

<p>NDK  :</p>
<pre class="no-pretty-print">
dlopen failed: cannot locate symbol "__system_property_get" referenced by ...
</pre>


<p>
           .
</p>

<ul>
  <li>libandroid_runtime.so getJavaVM  getJNIEnv
 JNI    .
<pre class="no-pretty-print">
AndroidRuntime::getJavaVM -&gt; GetJavaVM from &lt;jni.h&gt;
AndroidRuntime::getJNIEnv -&gt; JavaVM::GetEnv or
JavaVM::AttachCurrentThread from &lt;jni.h&gt;.
</pre>
  </li>

  <li>{@code libcutils.so} {@code property_get}
 {@code alternative __system_property_get}   .
    ,  include  {@code __system_property_get} .
<pre>
#include &lt;sys/system_properties.h&gt;
</pre>
  </li>

  <li>{@code libcrypto.so} {@code SSL_ctrl}
   .  , {@code .so}
 {@code libcyrpto.a}   BoringSSL  OpenSSL
 {@code libcrypto.so}    .
  </li>
</ul>

<h2 id="afw">Android for Work</h2>
<p>
  Android N Android for Work
 .  ,  ,
           . Android for Work

  .
</p>

<ul>
  <li>DPC    ,
  . N SDK
      ,   (DPC) <code>DevicePolicyManager.setCertInstallerPackage()</code>
 ,
 .
    <code>IllegalArgumentException</code>
.
  </li>

  <li>
 .
   {@code DevicePolicyManager.resetPassword()}
  .
  , PIN        .
  </li>

  <li>
    . <code>DISALLOW_MODIFY_ACCOUNTS</code>
          API   .
  </li>

  <li>        .
      <code>DISALLOW_ADD_USER</code>
 .
. , <code>CreateUser()</code>
 <code>createAndInitializeUser()</code>   ,
<code>DevicePolicyManager.createAndManageUser()</code>  .
  </li>

  <li>      .
 <code>DevicePolicyManagewr.getWifiMacAddress()</code>
 Wi-Fi MAC    .
Wi-Fi       {@code null}  .
  </li>

  <li>Work Mode      .
           .
     .
</ul>

<p>
  Android N Android for Work
<a href="{@docRoot}preview/features/afw.html">Android for Work </a> .
</p>

<h2 id="annotations"> </h2>

<p>
Android N      .            .

    .
</p>

<ul>
   <li>{@code VISIBILITY_BUILD}:    .</li>
   <li>{@code VISIBILITY_SYSTEM}:
   .</li>
</ul>

<p>
   ,
   . {@code @Retention(RetentionPolicy.RUNTIME)}   .
</p>

<h2 id="other">  </h2>

<ul>
<li> Android N    API
  ,    .
     .    Recents
     .

<p>
      .
DDMS

 .
</p>

<p>
N          ,
      .
</p>
</li>

<li>
Android N        ,
      .
(<strong>Setting</strong> &gt;
<strong>Display</strong> &gt; <strong>Font size</strong>)     , Recents
   .
</li>

<li>
  Android  ,
TCP        . Android N   .
     {@code android.os.NetworkOnMainThreadException} .
,
    ANR  (jank) ,      .
</li>

<li>
{@code Debug.startMethodTracing()}   ,
SD      ,

.  ,   API   {@code WRITE_EXTERNAL_STORAGE}      .
</li>

<li>
  API
 {@link android.os.Binder}      ,
 {@code TransactionTooLargeExceptions}
    {@code RuntimeExceptions}  .

{@link android.app.Activity#onSaveInstanceState Activity.onSaveInstanceState()}
    ,  Android N    {@code ActivityThread.StopInfo}
{@code RuntimeException}  .
</li>

<li>
 {@link java.lang.Runnable}  {@link android.view.View}
{@link android.view.View}
   ,
{@link android.view.View}  {@link java.lang.Runnable}   ,
{@link java.lang.Runnable}
{@link android.view.View}
 .      .
<ul>
   <li>  UI     {@link android.view.View}   ,
 {@link java.lang.Runnable}     .
   </li>
   <li>{@link java.lang.Runnable}
   {@link java.lang.Runnable}    .</li>
</ul>
</li>

<li>
{@link android.Manifest.permission#DELETE_PACKAGES DELETE_PACKAGES}

 Android N     ,
  .
{@link android.content.pm.PackageInstaller#uninstall PackageInstaller.uninstall()}
{@link android.content.pm.PackageInstaller#STATUS_PENDING_USER_ACTION STATUS_PENDING_USER_ACTION}
   .
</li>

</ul>