我有断点设置,但是似乎是忽略(或从未见过).
我的代码如下我试图将一个sql数据库备份到SD卡.
当我在eclipse中运行它(而不是调试模式)时,我从onPreExecute得到消息,并在短时间内通过onPostExecute的消息.
我已经在ExportDatabaseFileTask的几乎每一行都设置了BreakPoints.
当我在eclipse中运行(在调试模式下)时,我停止在onPreExecute的断点处,然后当我进一步调试时,Debugger所做的很多NEXT LINE是：
mDbHelper.open();
然后我继续阅读正常代码的其余部分,然后放在AVD上,显示从onPreExecute的消息,它将显然保持“永远”.
我没有看到BREAKPOINTED中的任何一行：
doInBackground
onPostExecute
复制文件
所以我必须尊重不同意我没有被断定或不被执行的评论.所以,我会回答我的问题：你如何调试(Step THROUGH)一个AsyncTask的doInBackground代码？
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 {
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();
}
}
}
}