如何调试doInBackground $ C $的的AsyncTask了C [英] How can I debug doInBackground code of an AsyncTask

问题描述

我有断点设置，但他们似乎忽略了（或者从来没见过）。

I have breakpoints set, but they seem to be ignore (or never seen).

我的code是如下。我想备份SQL数据库到SD卡。

My code is below. I'm trying to backup a sql db to an SD card.

当我在Eclipse中运行它（不调试模式下），我得到的消息来自于preExecute，随后不久从onPostExecute消息。

When I RUN it (not Debug mode) in eclipse, I get the message from the onPreExecute and followed shortly by the message from the onPostExecute.

我设置断点几乎ExportDatabaseFileTask的每一行。

I have BreakPoints set in almost every line of the ExportDatabaseFileTask.

当我运行它（在调试模式下）在Eclipse中，我停在断点在preExecute，然后我再走一步，在下一个线路调试器去是：

When I RUN it (in Debug mode) in eclipse, I stop at the breakpoints in onPreExecute, and then as I step further, THE VERY NEXT LINE the Debugger goes to is:

mDbHelper.open（）;

mDbHelper.open();

我再踩通过正常的code中的休息，我离开了问心无愧的AVD显示从上preExecute，wher它显然将永远留消息。

I then step through the rest of the normal code and am left wth the AVD showing the message from the onPreExecute, wher it will apparently STAY FOREVER.

我看不到任何BREAKPOINTED在行：

I do NOT see any of the lines BREAKPOINTED in:

doInBackground onPostExecute 的CopyFile

doInBackground onPostExecute copyFile

所以，我必须恭敬地与我没有它breakpointed或没有被执行的意见分歧。所以，我会reask我的问题：你如何调试（单步）的的AsyncTask的doInBackground code

So, I have to respectfully disagree with the comment that I don't have it breakpointed or it is not being executed. So, I'll reask my question: How do you debug (STEP THROUGH) doInBackground code of an AsyncTask?

        case BACKUP_ID:
            if (ScoreAGame.this.isExternalStorageAvail()) {
                mDbHelper.close();
                new ExportDatabaseFileTask().execute();
                mDbHelper.open();
            } else {
                Toast.makeText(ScoreAGame.this, "External storage is not available, unable to export data.",
                           Toast.LENGTH_SHORT).show();
            }
            return true;
        case RESTORE_ID:
            selectCourse();
            return true;
    }

    return super.onMenuItemSelected(featureId, item);
}

private boolean isExternalStorageAvail() {
    return Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
}

private class ExportDatabaseFileTask extends AsyncTask<String, Void, Boolean> {
    private final ProgressDialog dialog = new ProgressDialog(ScoreAGame.this);

    // can use UI thread here
    protected void onPreExecute() {
        this.dialog.setMessage("Exporting database...");
        this.dialog.show();
    }

    // automatically done on worker thread (separate from UI thread)
    protected Boolean doInBackground(final String... args) {

        File dbFile =
            new File(Environment.getDataDirectory() + "/data/com.discgolf/databases/discgolfdb.db");

        File exportDir = new File(Environment.getExternalStorageDirectory(), "discgolfbackup");
        if (!exportDir.exists()) {
            exportDir.mkdirs();
        }
        File file = new File(exportDir, dbFile.getName());

        try {
            file.createNewFile();
            this.copyFile(dbFile, file);
            return true;
        }
        catch (IOException e) {
            Log.e(TAG, e.getMessage(), e);
            return false;
        }
    }

    // can use UI thread here
    protected void onPostExecute(final Boolean success) {
        if (this.dialog.isShowing()) {
            this.dialog.dismiss();
        }
        if (success) {
            Toast.makeText(ScoreAGame.this, "Export successful!", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(ScoreAGame.this, "Export failed", Toast.LENGTH_SHORT).show();
        }
    }

    void copyFile(File src, File dst) throws IOException {
        FileChannel inChannel = new FileInputStream(src).getChannel();
        FileChannel outChannel = new FileOutputStream(dst).getChannel();
        try {
            inChannel.transferTo(0, inChannel.size(), outChannel);
        }
        finally {
            if (inChannel != null) {
                inChannel.close();
            }
            if (outChannel != null) {
                outChannel.close();
            }
        }
    }

}

推荐答案

检查该<一href="http://stackoverflow.com/questions/4770587/how-do-i-use-the-eclipse-debugger-in-an-asynctask-when-developing-for-android">How做开发的机器人，当我使用Eclipse调试器中的AsyncTask？

将下面的code片段doInBackground的开头：

Put the following code fragment in the beginning of doInBackground:

android.os.Debug.waitForDebugger（）;

android.os.Debug.waitForDebugger();

然后，当你在一个线程中设置一个断点，日食会发现它。

Then when you set a breakpoint in that thread, eclipse will find it.

礼貌：sargas

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