android - 将位图保存到文件功能

Question

我正在尝试使用我创建的函数直接将位图保存到文件和特定文件中。它不工作。它在 bitmap.compress 部分(here3 之前)之后崩溃。

    File dir = new File(filepath);

    if(!dir.exists())dir.mkdirs();

    File file = new File(Environment.getExternalStorageDirectory() + filepath, side + ".png");
    FileOutputStream fOut = new FileOutputStream(file);

    bitmap.compress(Bitmap.CompressFormat.PNG, 85, fOut);
    fOut.flush();
    fOut.close();

    System.out.println(filepath);

    bitmap.recycle();
    System.gc();

---

错误日志:

06-29 00:16:38.089: D/AndroidRuntime(3260): Shutting down VM
06-29 00:16:38.089: W/dalvikvm(3260): threadid=1: thread exiting with uncaught exception (group=0xb587f4f0)
06-29 00:16:38.089: E/AndroidRuntime(3260): FATAL EXCEPTION: main
06-29 00:16:38.089: E/AndroidRuntime(3260): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=0, result=-1, data=Intent { act=android.intent.action.VIEW dat=content://org.openintents.filemanager/mimetype//mnt/sdcard/download/02977_awreckedboatintheocean_1280x1024.jpg }} to activity {com.polygonattraction.testbirds/com.polygonattraction.testbirds.functions.SelectImageSource}: java.lang.IllegalStateException: Can't compress a recycled bitmap
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread.deliverResults(ActivityThread.java:2532)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread.handleSendResult(ActivityThread.java:2574)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread.access$2000(ActivityThread.java:117)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:961)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.os.Looper.loop(Looper.java:130)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread.main(ActivityThread.java:3683)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at java.lang.reflect.Method.invokeNative(Native Method)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at java.lang.reflect.Method.invoke(Method.java:507)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at dalvik.system.NativeStart.main(Native Method)
06-29 00:16:38.089: E/AndroidRuntime(3260): Caused by: java.lang.IllegalStateException: Can't compress a recycled bitmap
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.graphics.Bitmap.checkRecycled(Bitmap.java:180)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.graphics.Bitmap.compress(Bitmap.java:581)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at com.polygonattraction.testbirds.functions.Functions.SaveToFile(Functions.java:144)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at com.polygonattraction.testbirds.functions.SelectImageSource.onActivityResult(SelectImageSource.java:113)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.Activity.dispatchActivityResult(Activity.java:3908)
06-29 00:16:38.089: E/AndroidRuntime(3260):     at android.app.ActivityThread.deliverResults(ActivityThread.java:2528)

Answer 1

1. 您需要在 manifest.xml 中获得适当的权限:

   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
   

2. out.flush() 检查 out 不为空..

3. String file_path = Environment.getExternalStorageDirectory().getAbsolutePath() + 
                               "/PhysicsSketchpad";
   File dir = new File(file_path);
   if(!dir.exists())
       dir.mkdirs();
   File file = new File(dir, "sketchpad" + pad.t_id + ".png");
   FileOutputStream fOut = new FileOutputStream(file);
   
   bmp.compress(Bitmap.CompressFormat.PNG, 85, fOut);
   fOut.flush();
   fOut.close();