Android 读取AssetFileDescriptor时发生IOException

我正在尝试使用以下代码从Android

/assets

文件夹读取位图：

AssetFileDescriptor fd = getAssets().openFd("pic1.jpg")
Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd.getFileDescriptor());

我收到的异常表明文件权限错误：

java.io.IOException: read failed: EBADF (Bad file number)
    at libcore.io.IoBridge.read(IoBridge.java:432)
    at java.io.FileInputStream.read(FileInputStream.java:179)
    at java.io.BufferedInputStream.fillbuf(BufferedInputStream.java:168)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:309)
    at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
    at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:587)
    at android.graphics.BitmapFactory.decodeFileDescriptor(BitmapFactory.java:670)
    at android.graphics.BitmapFactory.decodeFileDescriptor(BitmapFactory.java:688)

尝试从输入流中读取会产生类似的异常：

AssetFileDescriptor fd = getAssets().openFd("pic1.jpg");
FileInputStream is = fd.createInputStream();
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.io.IOException: lseek failed: EBADF (Bad file number)
Stack trace:
  at java.io.FileInputStream.skip(FileInputStream.java:197)
  at android.content.res.AssetFileDescriptor$AutoCloseInputStream.<init>(AssetFileDescriptor.java:173)
  at android.content.res.AssetFileDescriptor.createInputStream(AssetFileDescriptor.java:138)

InputStream is = getAssets().open("pic1.jpg");
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.lang.NullPointerException: asset
  at android.content.res.AssetManager.seekAsset(Native Method)
  at android.content.res.AssetManager.access$600(AssetManager.java:35)
  at android.content.res.AssetManager$AssetInputStream.mark(AssetManager.java:567)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:572)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:643)

例外情况：

AssetFileDescriptor fd = getAssets().openFd("pic1.jpg");
FileInputStream is = fd.createInputStream();
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.io.IOException: lseek failed: EBADF (Bad file number)
Stack trace:
  at java.io.FileInputStream.skip(FileInputStream.java:197)
  at android.content.res.AssetFileDescriptor$AutoCloseInputStream.<init>(AssetFileDescriptor.java:173)
  at android.content.res.AssetFileDescriptor.createInputStream(AssetFileDescriptor.java:138)

InputStream is = getAssets().open("pic1.jpg");
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.lang.NullPointerException: asset
  at android.content.res.AssetManager.seekAsset(Native Method)
  at android.content.res.AssetManager.access$600(AssetManager.java:35)
  at android.content.res.AssetManager$AssetInputStream.mark(AssetManager.java:567)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:572)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:643)

例外情况：

AssetFileDescriptor fd = getAssets().openFd("pic1.jpg");
FileInputStream is = fd.createInputStream();
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.io.IOException: lseek failed: EBADF (Bad file number)
Stack trace:
  at java.io.FileInputStream.skip(FileInputStream.java:197)
  at android.content.res.AssetFileDescriptor$AutoCloseInputStream.<init>(AssetFileDescriptor.java:173)
  at android.content.res.AssetFileDescriptor.createInputStream(AssetFileDescriptor.java:138)

InputStream is = getAssets().open("pic1.jpg");
Bitmap bitmap = BitmapFactory.decodeStream(is);

java.lang.NullPointerException: asset
  at android.content.res.AssetManager.seekAsset(Native Method)
  at android.content.res.AssetManager.access$600(AssetManager.java:35)
  at android.content.res.AssetManager$AssetInputStream.mark(AssetManager.java:567)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:572)
  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:643)

---

读取资产的正确方法是什么？

问题是我没有从主线程读取资产。在我开发的应用程序中，两个列表项可以同时加载相同的、相当大的资产

---

简言之，如果在另一个线程试图访问该文件时仍在读取该文件，则会抛出一个带有“lseek failed:EBADF（坏文件号）”的

IOException

。

试试

AssetFileDescriptor fd=getAssets（）.openFd（“/pics/”+assets[i]）

，它抛出一个

FileNotFoundException

，这也是我在提供一个不存在的文件名时收到的结果；我将用堆栈跟踪更新问题。奇怪的是，在应用程序崩溃之前，资源确实出现了一段时间。我假设由于代码中其他地方的错误，资产试图被读取两次。我会简化事情，马上回来。@amal调试这个很头疼，所以我感觉到了你的痛苦。