在我的Android应用中，我是根据图片URL创建位图的。下面是我编写的用于从图像URL创建位图的代码-
public static Bitmap getBitmapFromURL(String src)
{
try
{
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
URL url = new URL(src);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
我的应用程序在Play商店中，此代码会影响少数设备，因为它们会收到“输入调度超时” ANR。以下是我从Google Play控制台的“ ANR和崩溃”部分获得的ANR详细信息-
“ 输入调度超时（等待发送非键事件，因为触摸的窗口尚未完成处理超过500.0ms之前传递给它的某些输入事件。等待队列长度：60。等待队列头部年龄：10502.8毫秒。） ”
以下是来自Google Play控制台的完整日志-
"main" prio=5 tid=1 Native
| group="main" sCount=1 dsCount=0 obj=0x75a2c598 self=0xa4e84400
| sysTid=522 nice=0 cgrp=default sched=0/0 handle=0xa7d13534
| state=S schedstat=( 0 0 0 ) utm=114 stm=42 core=1 HZ=100
| stack=0xbe467000-0xbe469000 stackSize=8MB
| held mutexes=
#00 pc 0000000000048cb4 /system/lib/libc.so (__ppoll+20)
#01 pc 000000000001cf3f /system/lib/libc.so (poll+46)
#02 pc 0000000000012cb7 /system/lib/libjavacrypto.so (???)
#03 pc 000000000000f24b /system/lib/libjavacrypto.so (???)
#04 pc 000000000000e5cd /system/framework/arm/boot-conscrypt.oat (Java_com_android_org_conscrypt_NativeCrypto_SSL_1read__JLjava_io_FileDescriptor_2Lcom_android_org_conscrypt_NativeCrypto_00024SSLHandshakeCallbacks_2_3BIII+192)
at com.android.org.conscrypt.NativeCrypto.SSL_read (Native method)
at com.android.org.conscrypt.OpenSSLSocketImpl$SSLInputStream.read (OpenSSLSocketImpl.java:761)
- locked <0x06eb358f> (a java.lang.Object)
at com.android.okhttp.okio.Okio$2.read (Okio.java:142)
at com.android.okhttp.okio.AsyncTimeout$2.read (AsyncTimeout.java:218)
at com.android.okhttp.okio.RealBufferedSource.indexOf (RealBufferedSource.java:312)
at com.android.okhttp.okio.RealBufferedSource.indexOf (RealBufferedSource.java:306)
at com.android.okhttp.okio.RealBufferedSource.readUtf8LineStrict (RealBufferedSource.java:202)
at com.android.okhttp.internal.http.HttpConnection.readResponse (HttpConnection.java:210)
at com.android.okhttp.internal.http.HttpTransport.readResponseHeaders (HttpTransport.java:81)
at com.android.okhttp.internal.http.HttpEngine.readNetworkResponse (HttpEngine.java:960)
at com.android.okhttp.internal.http.HttpEngine.readResponse (HttpEngine.java:836)
at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute (HttpURLConnectionImpl.java:480)
at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse (HttpURLConnectionImpl.java:422)
at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream (HttpURLConnectionImpl.java:256)
at com.android.okhttp.internal.huc.DelegatingHttpsURLConnection.getInputStream (DelegatingHttpsURLConnection.java:210)
at com.android.okhttp.internal.huc.HttpsURLConnectionImpl.getInputStream (HttpsURLConnectionImpl.java)
at come.xyz.myapp.util.AppHelper.getBitmapFromURL (AppHelper.java:66)
at come.xyz.myapp.Adapters.ScratchersAdapter.instantiateItem (ScratchersAdapter.java:706)
at android.support.v4.view.ViewPager.addNewItem (ViewPager.java:1004)
at android.support.v4.view.ViewPager.populate (ViewPager.java:1218)
at android.support.v4.view.ViewPager.populate (ViewPager.java:1086)
at android.support.v4.view.ViewPager.setAdapter (ViewPager.java:534)
at come.xyz.myapp.widgets.InfiniteViewPager.setAdapter (InfiniteViewPager.java:40)
at come.xyz.myapp.Fragments.DailyScratchersFragment.updateAdapter (DailyScratchersFragment.java:965)
at come.xyz.myapp.Fragments.DailyScratchersFragment.onCaughtContent (DailyScratchersFragment.java:750)
at come.xyz.coresdk.CoreLibrary.onCaughtContent (CoreLibrary.java:591)
at come.xyz.coresdk.asynctasks.CatchScratcherSetTask.onPostExecute (CatchScratcherSetTask.java:82)
at come.xyz.coresdk.asynctasks.CatchScratcherSetTask.onPostExecute (CatchScratcherSetTask.java:22)
at android.os.AsyncTask.finish (AsyncTask.java:660)
at android.os.AsyncTask.-wrap1 (AsyncTask.java)
at android.os.AsyncTask$InternalHandler.handleMessage (AsyncTask.java:677)
at android.os.Handler.dispatchMessage (Handler.java:102)
at android.os.Looper.loop (Looper.java:154)
at android.app.ActivityThread.main (ActivityThread.java:6317)
at java.lang.reflect.Method.invoke! (Native method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:872)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:762)
关于stackoverflow上的同一问题，之前发布了几个问题，但我发现这些问题都不对我有用。请让我知道我是否可以提供有关此问题的更多信息。谢谢。
答案 0 :(得分：2)
我相信您正在主线程上下载映像，这将导致ANR，我认为您需要在asynctask之类的后台线程中进行映像，或使用这些第三方之一 https://github.com/bumptech/glide或http://square.github.io/picasso/
答案 1 :(得分：1)
可能是导致问题的以下行
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
与其通过这种方法执行网络功能，而是为其创建一个AsyncTask，引起ANR的原因可能是因为该过程太冗长，所以请不要使用AsyncTask来启用strickmode
答案 2 :(得分：1)
实际上将“从URL创建位图”代码放在Asynctask中解决了我的问题。下面是我的代码-
public class GetBitmapTask extends AsyncTask<String, Void, Bitmap>
{
@Override
protected Bitmap doInBackground(String... urls)
{
Bitmap map = null;
for (String url : urls)
{
map = createBitmapFromURL(url);
}
return map;
}
// Sets the Bitmap returned by doInBackground
@Override
protected void onPostExecute(Bitmap resultBitmap)
{
}
public Bitmap createBitmapFromURL(String src)
{
try
{
URL url = new URL(src);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
}
下面是我如何称呼此任务-
Bitmap mBitmap = new GetBitmapTask().execute(strImgUrl).get();