致命异常:安卓中的异步任务#1

Question

可能是重复的问题，但我没有找到任何解决方案。

我想从文件夹中获取文件名并使用异步显示它，但我收到以下错误FATAL EXCEPTION: AsyncTask #1 Error java.lang.RuntimeException: An error occured while executing doInBackground()

下面是我的代码

 private static String[] listArr ;
 private static  String[] listArrview  ;
 private static final ArrayList<String> ary_user_pdf = new ArrayList<String>();
 private static final ArrayList<String> ary_user_pdfview = new ArrayList<String>();
 new AsyncAction().execute(null, null, null);

填充数据(( 函数

if(file.exists() && file.listFiles().length>0)
{
    File list[] = file.listFiles();
    for( int i=0; i< list.length; i++)
    {
        //myList.add( list[i].getName() );
        ary_user_pdf.add(list[i].getName());
        ary_user_pdfview.add(list[i].getName());
    }
    listArr = new String[ary_user_pdf.size()];
    listArr = ary_user_pdf.toArray(listArr);
    listArrview = new String[ary_user_pdfview.size()];
    listArrview = ary_user_pdfview.toArray(listArrview);
}

private class AsyncAction extends AsyncTask<String, Void, String> {
        public boolean status = false;
        private ProgressDialog pd;
        @Override
        protected String doInBackground(String... arg0) {
            // TODO Auto-generated method stub
            try {
                fillData();
                status = true;
            } catch (Exception e) {
                // TODO: handle exception
            }
            return null;
        }
        @Override
        protected void onPostExecute(String result) {
            pd.dismiss();

                MyArrayAdapter adapter = new MyArrayAdapter(Downloadpdf.this,
                        listArr);
                lstSub.setAdapter(adapter);
        }
        protected void onPreExecute() {
            // TODO Auto-generated method stub
            super.onPreExecute();
            pd = new ProgressDialog(Downloadpdf.this);
            pd.setTitle("PDF");
            pd.setMessage("Please wait while we are loading PDF.");
            pd.setIndeterminate(true);
            pd.setCancelable(false);
            pd.show();
        }

.LOG：

10-10 13:05:19.791: E/AndroidRuntime(19301): FATAL EXCEPTION: AsyncTask #1
10-10 13:05:19.791: E/AndroidRuntime(19301): java.lang.RuntimeException: An error occured while executing doInBackground()
10-10 13:05:19.791: E/AndroidRuntime(19301):    at android.os.AsyncTask$3.done(AsyncTask.java:200)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:274)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.FutureTask.setException(FutureTask.java:125)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:308)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.FutureTask.run(FutureTask.java:138)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.lang.Thread.run(Thread.java:1019)
10-10 13:05:19.791: E/AndroidRuntime(19301): Caused by: java.lang.NoSuchMethodError: android.os.Bundle.getString
10-10 13:05:19.791: E/AndroidRuntime(19301):    at com.paper.solution.Downloadpdf.fillData(Downloadpdf.java:162)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at com.paper.solution.Downloadpdf$AsyncAction.doInBackground(Downloadpdf.java:112)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at com.paper.solution.Downloadpdf$AsyncAction.doInBackground(Downloadpdf.java:1)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at android.os.AsyncTask$2.call(AsyncTask.java:185)
10-10 13:05:19.791: E/AndroidRuntime(19301):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:306)
10-10 13:05:19.791: E/AndroidRuntime(19301):    ... 4 more
10-10 13:05:20.841: E/WindowManager(19301): Activity com.paper.solution.Downloadpdf has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4052ee20 that was originally added here
10-10 13:05:20.841: E/WindowManager(19301): android.view.WindowLeaked: Activity com.paper.solution.Downloadpdf has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4052ee20 that was originally added here
10-10 13:05:20.841: E/WindowManager(19301):     at android.view.ViewRoot.<init>(ViewRoot.java:258)
10-10 13:05:20.841: E/WindowManager(19301):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:148)
10-10 13:05:20.841: E/WindowManager(19301):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
10-10 13:05:20.841: E/WindowManager(19301):     at android.view.Window$LocalWindowManager.addView(Window.java:424)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.Dialog.show(Dialog.java:241)
10-10 13:05:20.841: E/WindowManager(19301):     at com.paper.solution.Downloadpdf$AsyncAction.onPreExecute(Downloadpdf.java:151)
10-10 13:05:20.841: E/WindowManager(19301):     at android.os.AsyncTask.execute(AsyncTask.java:391)
10-10 13:05:20.841: E/WindowManager(19301):     at com.paper.solution.Downloadpdf.layout(Downloadpdf.java:98)
10-10 13:05:20.841: E/WindowManager(19301):     at com.paper.solution.Downloadpdf.onCreate(Downloadpdf.java:71)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1586)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1638)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.ActivityThread.access$1500(ActivityThread.java:117)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:928)
10-10 13:05:20.841: E/WindowManager(19301):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-10 13:05:20.841: E/WindowManager(19301):     at android.os.Looper.loop(Looper.java:123)
10-10 13:05:20.841: E/WindowManager(19301):     at android.app.ActivityThread.main(ActivityThread.java:3647)
10-10 13:05:20.841: E/WindowManager(19301):     at java.lang.reflect.Method.invokeNative(Native Method)
10-10 13:05:20.841: E/WindowManager(19301):     at java.lang.reflect.Method.invoke(Method.java:507)
10-10 13:05:20.841: E/WindowManager(19301):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
10-10 13:05:20.841: E/WindowManager(19301):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
10-10 13:05:20.841: E/WindowManager(19301):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

您正在调用 Bundle.getString(String， String(，它仅在没有 API 12 的设备上的 API 12 中添加。

确保对属于高于 minSdk 值的 API 的方法的调用具有正确的目标(使用 @TargetApi 注释(，或者不使用它们，并且仅使用 API 1 中添加的 Bundle.getString(String) 方法。

Answer 2

这样做

new AsyncAction().execute();

然后在异步任务中

private class AsyncAction extends AsyncTask<Void, Void, Void> {
    public boolean status = false;
    private ProgressDialog pd;
    @Override
    protected Void doInBackground(Void... arg0) {
        // TODO Auto-generated method stub
        try {
            fillData();
            status = true;
        } catch (Exception e) {
            // TODO: handle exception
        }
        return null;
    }
    @Override
    protected void onPostExecute(Void result) {
        pd.dismiss();

            MyArrayAdapter adapter = new MyArrayAdapter(Downloadpdf.this,
                    listArr);
            lstSub.setAdapter(adapter);
    }
    protected void onPreExecute() {
        // TODO Auto-generated method stub
        super.onPreExecute();
        pd = new ProgressDialog(Downloadpdf.this);
        pd.setTitle("PDF");
        pd.setMessage("Please wait while we are loading PDF.");
        pd.setIndeterminate(true);
        pd.setCancelable(false);
        pd.show();
    }

Answer 3

检查是否已实例化文件对象

File

file=new File(path(; in 方法 filldata((