如何从原始文件夹中读取pdf文件?

时间:2012-06-20 21:22:08

标签: java android

如果设备有任何pdfreader,我想从原始文件夹中读取pdf文件。 这是我的代码:

 Intent intent = new Intent(Intent.ACTION_VIEW,
              Uri.parse("android.resource://com.powergroupbd.pdfreader/raw" + R.raw.androidtasksmwp));

    intent.setType("application/pdf");
    PackageManager pm = getPackageManager();
    List<ResolveInfo> activities = pm.queryIntentActivities(intent, 0);
    if (activities.size() > 0) {
        startActivity(intent);
    } else {
       Toast.makeText(getApplicationContext(), "No pdfreader  found", Toast.LENGTH_LONG).show();
    }

但是当我运行这个项目时,它显示错误。这是logcat结果:

06-21 02:05:04.408: W/dalvikvm(7763): threadid=1: thread exiting with uncaught exception (group=0x40015560)
06-21 02:05:04.418: E/AndroidRuntime(7763): FATAL EXCEPTION: main
06-21 02:05:04.418: E/AndroidRuntime(7763): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.qo.android.htcgep/com.qo.android.am.pdflib.app.RenderScreen}: java.lang.NullPointerException
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.os.Handler.dispatchMessage(Handler.java:99)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.os.Looper.loop(Looper.java:130)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread.main(ActivityThread.java:3683)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at java.lang.reflect.Method.invokeNative(Native Method)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at java.lang.reflect.Method.invoke(Method.java:507)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at dalvik.system.NativeStart.main(Native Method)
06-21 02:05:04.418: E/AndroidRuntime(7763): Caused by: java.lang.NullPointerException
06-21 02:05:04.418: E/AndroidRuntime(7763):  at com.qo.android.am.pdflib.app.RenderScreen.onNewIntent(Unknown Source)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at com.qo.android.am.pdflib.app.RenderScreen.onCreate(Unknown Source)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-21 02:05:04.418: E/AndroidRuntime(7763):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
06-21 02:05:04.418: E/AndroidRuntime(7763):  ... 11 more
06-21 02:05:04.418: W/ActivityManager(96):   Force finishing activity com.qo.android.htcgep/com.qo.android.am.pdflib.app.RenderScreen

我做错了什么?请帮助.. :(

2 个答案:

答案 0 :(得分:1)

我从未尝试过这样做,但我通过以下程序非常成功地使用原始资源:

  1. 获取和输入资源的InputStream
      

    fileResourceStream =   Activity.getResources()。openRawResource(R.raw.androidclient)); // R文件   引用资源ID。在你的情况下它将是   R.raw.androidtasksmwp。

  2.   
  3. 使用此InputStream我将资源文件复制(通常一旦安装了应用程序)到设备内存或SD卡(决定是你的)。   可以设计出类似的东西:

    BufferedInputStream bIS = new BufferedInputStream(
    fileResourceStream);
    try {
            BufferedOutputStream bOS = new BufferedOutputStream(
            new FileOutputStream(Globals.applicationDirPath
                    + Globals.exeFileName, false));
    
            int BUFFER_SIZE = 4096;
            byte[] buff = new byte[BUFFER_SIZE];
            int bytesRead = bIS.read(buff, 0, BUFFER_SIZE);
            while (bytesRead >= 0) {
                bOS.write(buff, 0, bytesRead);
                bytesRead = bIS.read(buff, 0, BUFFER_SIZE);
            }
            bIS.close();
            bOS.flush();
            bOS.close();
    }// try {
    catch (Exception e) {
            Globals.log("Exception in checkAndCopyClientToMemory."
            + e.toString());
    }
    
  4. 在任何应用程序中打开复制的文件/作为文件用于任何目的。

答案 1 :(得分:0)

我认为你可能在“... / raw”之后错过了一个“/”所以uri是不正确的。

Uri.parse("android.resource://com.powergroupbd.pdfreader/raw" + R.raw.androidtasksmwp)

但是我不确定你是否可以从这样的外部包中访问资源,你可能需要将它复制到SD卡然后用意图打开它