DexClassLoader在Android蜂窝 [英] DexClassLoader on Android Honeycomb

问题描述

我正在试图通过加载外部库项目 DexClassLoader。这2.3工作pretty的还有：

I'm working on a project that tries to load an external library via DexClassLoader. This worked pretty well in 2.3:

    public class FormularDisplayLoader {
public final static String PATH ="/data/data/at.mSystem.client/files/mSystem_Client_FormularLibrary.jar";
        private DexClassLoader classLoader;

            public FormularDisplayLoader(Context context){
                    this.context = context;
                    this.classLoader = new DexClassLoader("/data/data/at.mSystem.client/
    files/mSystem_Client_FormularLibrary.jar",
                        context.getFilesDir().getAbsolutePath(),
                        null,
                        FormularDisplayLoader.class.getClassLoader());
            }

            public View getDisplay(String className) throws ErrorCodeException{
                    try {
                            Class c = classLoader.loadClass(className);
                            Method m = c.getMethod("getDisplay", Context.class);
                            View ret = (View) m.invoke(c.newInstance(), context);
                            return ret;
                    } catch (Exception e) {
                            e.printStackTrace();
                            throw new
    ErrorCodeException(FormularErrorCode.NO_DISPLAY_AVAILABLE_FOR_FORMULAR);
                    }
            }

    }

不幸的是，试图端口时，该应用程序，以蜂窝（因为 此应用程序实际目标有片剂）的DexClassLoader引发 例外：

Unfortunately, when trying to port this app to Honeycomb (because the actual target for this app are tablets) the DexClassLoader throws an exception:

02-23 09:30:58.221: ERROR/dalvikvm(8022): Can't open dex cache '/data/
dalvik-cache/
data@[e-mail]@files@[e-mail]':
No such file or directory
02-23 09:30:58.221: INFO/dalvikvm(8022): Unable to open or create
cache for /data/data/at.mSystem.client/files/
mSystem_Client_FormularLibrary.jar (/data/dalvik-cache/
data@[e-mail]@files@[e-mail])
02-23 09:30:58.231: WARN/System.err(8022):
java.lang.ClassNotFoundException:
at.mSystem.client.formular.contract.ContractListFormularDisplay in
loader dalvik.system.DexClassLoader@40630308
02-23 09:30:58.241: WARN/System.err(8022):     at
dalvik.system.DexClassLoader.findClass(DexClassLoader.java:240)
02-23 09:30:58.241: WARN/System.err(8022):     at
java.lang.ClassLoader.loadClass(ClassLoader.java:548)
02-23 09:30:58.261: WARN/System.err(8022):     at
java.lang.ClassLoader.loadClass(ClassLoader.java:508)
02-23 09:30:58.261: WARN/System.err(8022):     at
at.mSystem.client.system.formularmodule.formular.FormularDisplayLoader.getDisplay(FormularDisplayLoader.java:
35)

这似乎是DexClassLoader忽略二路参数 （dexOutputDir），作为值 context.getFilesDir（）。getAbsolutePath（）在我的例子是/数据/数据​​/ at.mSystem.client /文件。

It seems like the DexClassLoader ignores the 2th parameter (dexOutputDir), as the value of context.getFilesDir().getAbsolutePath() in my example is "/data/data/ at.mSystem.client/files".

你有什么想法如何解决呢？或者，这是某种形式的 蜂窝错误？

Do you have any ideas how to solve that? Or is this some kind of honeycomb bug?

谢谢

罗兰

推荐答案

我知道这是一个古老的职位，但我最近需要一个答案，这一点没有升级到Android 3.1，所以我想我会分享我的解决方案。

I know this is an old post, but I recently needed an answer to this without upgrading to Android 3.1, so I thought I would share my solution.

我用，而不是DexClassLoader的DexFile类，因为它让我通过输出文件，从而绕开问题被忽略的输出目录。

I used the "DexFile" class instead of the "DexClassLoader", since it allowed me to pass the output file, thus getting around the issue with the output directory being ignored.

下面是我的code：

final File dexClasses = new File("/sdcard/dexcontainer.zip");
DexFile dexFile = DexFile.loadDex(dexClasses.getAbsolutePath(), getFilesDir().getAbsolutePath() + "/outputdexcontainer.dex", 0);

Enumeration<String> classFileNames = dexFile.entries();
while (classFileNames.hasMoreElements())
{
  String className = classFileNames.nextElement();
  dexFile.loadClass(className, classLoader);
}

希望这可以帮助别人。

Hope this helps someone.

这篇关于DexClassLoader在Android蜂窝的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！