此代码用于将图片保存在 /Android/data/com.ocr.id/files/IDOCR/Number/
public static File save(Activity activity, Bitmap bm, String name) {
boolean mExternalStorageAvailable = false;
boolean mExternalStorageWriteable = false;
File number = null;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
// We can read and write the media
mExternalStorageAvailable = mExternalStorageWriteable = true;
OutputStream outStream = null;
File externalFilesDir = activity.getExternalFilesDir(null);
File outFile = new File(externalFilesDir, "IDOCR" + File.separator
+ "Numbers");
if (!outFile.exists())
outFile.mkdirs();
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
.format(new Date());
number = new File(outFile, timeStamp + "_" + name + ".PNG");
try {
outStream = new FileOutputStream(number);
bm.compress(Bitmap.CompressFormat.PNG, 100, outStream);
outStream.flush();
outStream.close();
outStream = null;
bm.recycle();
// bm = null;
System.gc();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
// We can only read the media
mExternalStorageAvailable = true;
mExternalStorageWriteable = false;
Toast.makeText(activity, "Your SDcared is read only.",
Toast.LENGTH_LONG).show();
} else {
// Something else is wrong. It may be one of many other states, but
// all we need
// to know is we can neither read nor write
mExternalStorageAvailable = mExternalStorageWriteable = false;
Toast.makeText(activity, "Your SDcared is unmounted.",
Toast.LENGTH_LONG).show();
}
return number;
}
该代码中的错误是什么，该代码抛出空指针异常作为这一行
bm.compress(Bitmap.CompressFormat.PNG, 100, outStream);
这段代码以前和我一起工作，但现在给我一个异常。