Question

我在这部分代码中发生了非法的参数异常：

boolean mExternalStorageAvailable = false;
boolean mExternalStorageWriteable = false;
String state = Environment.getExternalStorageState();

if (Environment.MEDIA_MOUNTED.equals(state)) {
    String root = Environment.getExternalStorageDirectory().toString();
    full_path = root+getResources().getString(R.string.app_name) ;
    File dir_path = getApplicationContext().getDir(full_path, MODE_PRIVATE);

这是错误日志：

03-08 12:26:23.717: E/AndroidRuntime(9234): FATAL EXCEPTION: main
03-08 12:26:23.717: E/AndroidRuntime(9234): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.streamfilesys/com.example.streamfilesys.MainActivity}: java.lang.IllegalArgumentException: File app_/storage/emulated/0/StreamFileSys contains a path separator
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.os.Handler.dispatchMessage(Handler.java:99)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.os.Looper.loop(Looper.java:137)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread.main(ActivityThread.java:5041)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at java.lang.reflect.Method.invokeNative(Native Method)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at java.lang.reflect.Method.invoke(Method.java:511)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at dalvik.system.NativeStart.main(Native Method)
03-08 12:26:23.717: E/AndroidRuntime(9234): Caused by: java.lang.IllegalArgumentException: File app_/storage/emulated/0/StreamFileSys contains a path separator
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ContextImpl.makeFilename(ContextImpl.java:1966)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ContextImpl.getDir(ContextImpl.java:1816)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.content.ContextWrapper.getDir(ContextWrapper.java:218)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at com.example.streamfilesys.MainActivity.onCreate(MainActivity.java:39)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.Activity.performCreate(Activity.java:5104)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
03-08 12:26:23.717: E/AndroidRuntime(9234):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
03-08 12:26:23.717: E/AndroidRuntime(9234):     ... 11 more

mainActivity第39行是

File dir_path = getApplicationContext().getDir(full_path, MODE_PRIVATE);

我该如何解决？

Answer 1

正如doc所说的Context.getDir (String name, int mode)：

检索，根据需要创建应用程序所在的新目录可以放置自己的自定义数据文件。您可以使用返回的文件用于创建和访问此目录中的文件的对象。请注意文件通过File对象创建的只能由您自己访问应用;你只能设置整个目录的模式，而不是个别档案。

表示不是通过文件分隔符传递文件名，而是需要将文件夹（Dir）名称作为第一个参数传递给getDir方法“：

File dir_path = getApplicationContext().getDir(
                        getResources().getString(R.string.app_name), MODE_PRIVATE);

修改

在外部SDCARD上创建Dir。将您的代码更改为：

File onsdcarddir = new File(Environment.getExternalStorageDirectory() + "/" +getResources().getString(R.string.app_name)); if (!onsdcarddir.exists()) { onsdcarddir.mkdir(); // create dir here }

还在AndroidManifest.xml中添加SDCARD权限：

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

在外部存储上创建/打开目录时出现IllegalArgumentException

1 个答案: