我正在尝试将某个活动中的位图保存到我创建的目录中,以便在外部存储设备上使用。将图像保存到SD卡(外部存储器,而不是外置SD卡)的方法在不同的类(和不同的包)中,所以我假设我需要上下文,但我找不到任何地方提供上下文(尝试了openFileOutput,但它只能接受不包含路径分隔符的字符串文件名)。当我运行代码时,在日志cat中会出现以下错误:
04-11 22:13:14.899: E/error(13833): /mnt/sdcard/myTomatoes/covers/378194.PNG: open failed: ENOENT (No such file or directory)
04-11 22:13:14.899: W/System.err(13833): java.io.FileNotFoundException: /mnt/sdcard/myTomatoes/covers/378194.PNG: open failed: ENOENT (No such file or directory)
04-11 22:13:14.899: W/System.err(13833): at libcore.io.IoBridge.open(IoBridge.java:416)
04-11 22:13:14.899: W/System.err(13833): at java.io.FileOutputStream.<init>(FileOutputStream.java:88)
04-11 22:13:14.899: W/System.err(13833): at java.io.FileOutputStream.<init>(FileOutputStream.java:73)
04-11 22:13:14.899: W/System.err(13833): at BL.ImageMethods.SaveImageToMemory(ImageMethods.java:60)
04-11 22:13:14.899: W/System.err(13833): at com.example.mytomatoes.MovieDetailsActivity$4.onClick(MovieDetailsActivity.java:337)
04-11 22:13:14.899: W/System.err(13833): at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:166)
04-11 22:13:14.899: W/System.err(13833): at android.os.Handler.dispatchMessage(Handler.java:99)
04-11 22:13:14.899: W/System.err(13833): at android.os.Looper.loop(Looper.java:137)
04-11 22:13:14.899: W/System.err(13833): at android.app.ActivityThread.main(ActivityThread.java:5039)
04-11 22:13:14.899: W/System.err(13833): at java.lang.reflect.Method.invokeNative(Native Method)
04-11 22:13:14.899: W/System.err(13833): at java.lang.reflect.Method.invoke(Method.java:511)
04-11 22:13:14.899: W/System.err(13833): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
04-11 22:13:14.899: W/System.err(13833): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
04-11 22:13:14.899: W/System.err(13833): at dalvik.system.NativeStart.main(Native Method)
04-11 22:13:14.899: W/System.err(13833): Caused by: libcore.io.ErrnoException: open failed: ENOENT (No such file or directory)
04-11 22:13:14.899: W/System.err(13833): at libcore.io.Posix.open(Native Method)
04-11 22:13:14.899: W/System.err(13833): at libcore.io.BlockGuardOs.open(BlockGuardOs.java:110)
04-11 22:13:14.899: W/System.err(13833): at libcore.io.IoBridge.open(IoBridge.java:400)
这些是我的权限:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
这是我保存文件的方法:
public static void SaveImageToMemory(Context context, Bitmap img, int rottenId) {
Log.i("SAVE IMAGE", "start save");
File sd = Environment.getExternalStorageDirectory();
File location = new File(sd.getAbsolutePath()+ "/myTomatoes/covers");
location.mkdir();
File dest = new File(location, rottenId + ".PNG");
try {
Log.i("SAVE IMAGE", "trying to save: " + dest.getPath());
FileOutputStream fos = new FileOutputStream(dest);
img.compress(Bitmap.CompressFormat.PNG, 100, fos);
fos.flush();
fos.close();
} catch (IOException e) {
Log.e("error", e.getMessage());
e.printStackTrace();
}
}
所有混乱的代码行用于创建File
对象,这是我的尝试结果...原始代码如下:
File location = new File(Environment.getExternalStorageDirectory() + "/myTomatoes/covers");
File dest = new File(location, rottenId + ".PNG");
我也尝试过先创建ByteArrayOutputStream
,将Bitmap压缩到其中,然后执行fos.write(mByteArrayOpStream.toByteArray())
,但并没有起作用。
顺便说一下,我正在使用模拟器,但我也在几个“Galaxy S”上检查过,出现了相同的错误……(当我尝试在手机或DDMS中浏览文件时,我可以看到它甚至没有创建文件夹……
mkdirs()
而不是mkdir()
,然后就可以正常工作了!甚至不需要将 Bitmap 压缩到ByteArrayOutputStream
,再将其写入文件,我只是将其压缩到 fos 中即可... - Aviel Gross