I'm currently doing a FTP download using MFC. Is a very simple program which takes 2 inputs from user and click a download button in order to download from server. Everything is fine and im able to download it from. But i realized this program can only be executed once. Either successful or fail user has to open the .exe again to download another file. I'm a beginner in C&C++ with a simple knowledge i put OnInitDialog() at the last line of the download function hopping it will loop back and initialize again. Of course it doesn't work. Below are my current codes for the download button
BOOL CFTPDOWNLOADDlg::Log_In(char* path, char* ID, char* password {
m_pFtpConnection = NULL;
try{
// path
// ID
// password
m_pFtpConnection = m_Session.GetFtpConnection(path,
ID,password,INTERNET_INVALID_PORT_NUMBER);
}
catch(CInternetException *pEx){
pEx->ReportError(MB_ICONEXCLAMATION);
m_pFtpConnection = NULL;
pEx->Delete();
return FALSE;
}
return TRUE;
}
BOOL CFTPDOWNLOADDlg::Download(){
m_Edit3.SetWindowText("Downloading..");
m_Session.EnableStatusCallback(TRUE);
if(m_pFtpConnection->GetFile(serv_Loc,host_Loc,
FALSE,FILE_ATTRIBUTE_NORMAL,FTP_TRANSFER_TYPE_BINARY,1) != 0){
MessageBox("Download Complete");
m_Edit3.SetWindowText("");}
else{
MessageBox("Download Fail");
return FALSE;
}
// Log_out Session
m_Session.Close();
m_pFtpConnection->Close();
if(m_pFtpConnection!=NULL) delete m_pFtpConnection;
else MessageBox("Download Complete");
return TRUE;
}
BOOL CFTPDOWNLOADDlg::get_Path(){
...
...
...
sprintf(serv_Loc,"soft\\%s\\%d\\%s.zip",s_No,r_Number,r_No);
sprintf(host_Loc,"%s\\%s.zip",buff2,r_No);
return TRUE;
}
void CFTPDOWNLOADDlg::OnCancel() {
// Log_out Session
m_Session.Close();
m_pFtpConnection->Close();
if(m_pFtpConnection!=NULL)
delete m_pFtpConnection;
CDialog::OnCancel();
}
void CFTPDOWNLOADDlg::OnDLButton() {
//get path from user input
get_Path();
// start download
Download();
}
I've tried to search online, i couldn't find anything which is close. Sorry for my poor explanation.
Thank you in advance for your kindness in replying
Here is what you need to do:
You should make CInternetSession m_Session; a member of your CWinApp-derived class.
You should call m_Session.Close() in ExitInstance() method of your CWinApp-derived class.
In your CDialog-derived class you should only deal with CFtpConnection related stuff. So when user clicks on Download button you should call GetFtpConnection() and initialize your m_pFtpConnection and do the rest. When download/upload is done call m_pFtpConnection->Close(); and delete m_pFtpConnection;
Please also use CString instead of char*. There are lots of benefits like automatic UNICODE support, etc.
Please also consider using CString::Format() method instead of sprintf().
You should also consider using threads to perform upload/download tasks in a separate worker thread. Use AfxBeginThread() to start the thread. This way you'll not affect Windows message pump that is a part of main application (GUI) thread. So your GUI wont lock up while you uploading/downloading files.
Related
my scenario is simple:i made a game using cocos2d-x and i want to download images (FB and Google play) for multi player users and show them once the download is done as texture for a button.
in ideal world, things work as expected.
things get tricky when those buttons got deleted before the download is done.
so the callback function is in weird state and then i get signal 11 (SIGSEGV), code 1 (SEGV_MAPERR)
and the app crashes
This is how i implmented it
I have a Layout class called PlayerIcon. the cpp looks like this
void PlayerIcon::setPlayer(string userName, string displayName, string avatarUrl){
try {
//some code here
downloadAvatar(_userName, _avatarUrl);
//some code here
}
catch(... ){
}
}
void PlayerIcon::downloadAvatar(std::string _avatarFilePath,std::string url) {
if(!isFileExist(_avatarFilePath)) {
try {
auto downloader = new Downloader();
downloader->onFileTaskSuccess=CC_CALLBACK_1(PlayerIcon::on_download_success,this);
downloader->onTaskError=[&](const network::DownloadTask& task,int errorCode,
int errorCodeInternal,
const std::string& errorStr){
log("error while saving image");
};
downloader->createDownloadFileTask(url,_avatarFilePath,_avatarFilePath);
}
catch (exception e)
{
log("error while saving image: test");
}
} else {
//set texture for button
}
}
void PlayerIcon::on_download_success(const network::DownloadTask& task){
_isDownloading = false;
Director::getInstance()->getScheduler()-> performFunctionInCocosThread(CC_CALLBACK_0(PlayerIcon::reload_avatar,this));
}
void PlayerIcon::reload_avatar(){
try {
// setting texture in UI thread
}
catch (...) {
log("error updating avatar");
}
}
As i said, things works fine until PlayerIcon is deleted before the download is done.
i dont know what happens when the call back of the download task point to a method of un object that s deleted (or flagged for deletion).
i looked in the downloader implementation and it doesn't provide any cancellation mechanism
and i'm not sure how to handle this
Also, is it normal to have 10% crash rate on google console for a cocos2dx game
any help is really appreciated
Do you delete de Downloader in de destructor of the PlayerIcon?
there is a destroy in the apple implementation witch is trigered by the destructor.
-(void)doDestroy
{
// cancel all download task
NSEnumerator * enumeratorKey = [self.taskDict keyEnumerator];
for (NSURLSessionDownloadTask *task in enumeratorKey)
{
....
DownloaderApple::~DownloaderApple()
{
DeclareDownloaderImplVar;
[impl doDestroy];
DLLOG("Destruct DownloaderApple %p", this);
}
In the demo code of cocos2d-x: DownloaderTest.cpp they use:
std::unique_ptr<network::Downloader> downloader;
downloader.reset(new cocos2d::network::Downloader());
instead of:
auto downloader = new Downloader();
It looks like you are building this network code as part of your scene tree. If you do a replaceScene/popScene...() call, while the async network software is running in the background, this will cause the callback to disappear (the scene will be deleted from the scene-stack) and you will get a SEGFAULT from this.
If this is the way you've coded it, then you might want to extract the network code to a global object (singleton) where you queue the requests and then grab them off the internet saving the results in the global-object's output queue (or their name and location) and then let the scene code check to see if the avatar has been received yet by inquiring on the global-object and loading the avatar sprite at this point.
Note, this may be an intermittent problem which depends on the speed of your machine and the network so it may not be triggered consistently.
Another solution ...
Or you could just set your function pointers to nullptr in your PlayerIcon::~PlayerIcon() (destructor):
downloader->setOnFileTaskSuccess(nullptr);
downloader->setOnTaskProgress(nullptr);
Then there will be no attempt to call your callback functions and the SEGFAULT will be avoided (Hopefully).
I'm writing to ask you some advices for a particular problem regarding SAPI engine. I have an application that can speak both to the speakers and to a WAV file. I also need some events to be aware, i.e. word boundary and end input.
m_cpVoice->SetNotifyWindowMessage(m_hWnd, TTS_MSG, 0, 0);
hr = m_cpVoice->SetInterest(SPFEI_ALL_EVENTS, SPFEI_ALL_EVENTS);
Just for test I added all events! When the engine speaks to speakers all events are triggered and sent to the m_hWnd window, but when I set output to the WAV file, none of them are sent
CSpStreamFormat fmt;
CComPtr<ISpStreamFormat> pOld;
m_cpVoice->GetOutputStream(&pOld);
fmt.AssignFormat(pOld);
SPBindToFile(file, SPFM_CREATE_ALWAYS, &m_wavStream, &fmt.FormatId(), fmt.WaveFormatExPtr());
m_cpVoice->SetOutput(m_wavStream, false);
m_cpVoice->Speak(L"Test", SPF_ASYNC, 0);
Where file is a path passed as argument.
Really this code is taken from the TTS samples found on the SAPI SDK. It seems a little bit obscure the part setting the format...
Can you help me in finding the problem? Or does anyone of you know a better way to write TTS to WAV? I can not use manager code, it should be better to use the C++ version...
Thank you very much for help
EDIT 1
This seems to be a thread problem and searching in the spuihelp.h file, that contains the SPBindToFile helper I found that it uses the CoCreateInstance() function to create the stream. Maybe this is where the ISpVoice object looses its ability to send event in its creation thread.
What do you think about that?
I adopted an on-the-fly solution that I think should be acceptable in most of the cases, In fact when you write speech on files, the major event you would be aware is the "stop" event.
So... take a look a the class definition:
#define TTS_WAV_SAVED_MSG 5000
#define TTS_WAV_ERROR_MSG 5001
class CSpeech {
public:
CSpeech(HWND); // needed for the notifications
...
private:
HWND m_hWnd;
CComPtr<ISpVoice> m_cpVoice;
...
std::thread* m_thread;
void WriteToWave();
void SpeakToWave(LPCWSTR, LPCWSTR);
};
I implemented the method SpeakToWav as follows
// Global variables (***)
LPCWSTR tMsg;
LPCWSTR tFile;
long tRate;
HWND tHwnd;
ISpObjectToken* pToken;
void CSpeech::SpeakToWave(LPCWSTR file, LPCWSTR msg) {
// Using, for example wcscpy_s:
// tMsg <- msg;
// tFile <- file;
tHwnd = m_hWnd;
m_cpVoice->GetRate(&tRate);
m_cpVoice->GetVoice(&pToken);
if(m_thread == NULL)
m_thread = new std::thread(&CSpeech::WriteToWave, this);
}
And now... take a look at the WriteToWave() method:
void CSpeech::WriteToWav() {
// create a new ISpVoice that exists only in this
// new thread, so we need to
//
// CoInitialize(...) and...
// CoCreateInstance(...)
// Now set the voice, i.e.
// rate with global tRate,
// voice token with global pToken
// output format and...
// bind the stream using tFile as I did in the
// code listed in my question
cpVoice->Speak(tMsg, SPF_PURGEBEFORESPEAK, 0);
...
Now, because we did not used the SPF_ASYNC flag the call is blocking, but because we are on a separate thread the main thread can continue. After the Speak() method finished the new thread can continue as follow:
...
if(/* Speak is went ok */)
::PostMessage(tHwn, TTS_WAV_SAVED_MSG, 0, 0);
else
::PostMessage(tHwnd, TTS_WAV_ERROR_MSG, 0, 0);
}
(***) OK! using global variables is not quite cool :) but I was going fast. Maybe using a thread with the std::reference_wrapper to pass parameters would be more elegant!
Obviously, when receiving the TTS messages you need to clean the thread for a next time call! This can be done using a CSpeech::CleanThread() method like this:
void CSpeech::CleanThread() {
m_thread->join(); // I prefer to be sure the thread has finished!
delete m_thread;
m_thread = NULL;
}
What do you think about this solution? Too complex?
I am trying to open simple .net exe/notepad.exe using process.start in hidden mode. and I need the process handle later to make the application.exe to make it visible after some time.
Able to get handle only in WindowStyle.Minimized, WindowStyle.Maximized, WindowStyle.Normal. In Hidden style, it gives me 0 always.
How to get handle without using Thread.Sleep. It requires us to wait few seconds, to get handle. some exe requires more wait time, based on its performance(huge data).
public static void LaunchExe()
{
var proc = new Process
{
StartInfo =
{
FileName = "Notepad.exe", //or any simple .net exe
WindowStyle = ProcessWindowStyle.Hidden
}
};
proc.Start();
proc.WaitForInputIdle(800); //is it possible to avoid this.
Thread.Sleep(3000); //is it possible to avoid this.
Console.WriteLine("handle {0}", proc.MainWindowHandle);
//ShowWindowAsync(proc.MainWindowHandle, 1); //planned to use, to make it visible.
}
You can do something like this:
IntPtr ptr = IntPtr.Zero;
while ((ptr = proc.MainWindowHandle) == IntPtr.Zero)
{ proc.WaitForInputIdle(1 * 60000); Thread.Sleep(10); } // (1*60000 = 1min, will give up after 1min)
That way you're not wasting any more time than you need to.
You can't get the handle of a hidden process.
According to MS: A process has a main window associated with it only if the process has a graphical interface. If the associated process does not have a main window, the MainWindowHandle value is zero. The value is also zero for processes that have been hidden, that is, processes that are not visible in the taskbar.
I think your only choice would be to start it normally, get the handle, then set it hidden.
This might cause some flicker, but it should work. To mitigate the flicker, you could start it minimized...
I am using LWUIT ResrouceEditor(latest SVN code revision 1513) to generate a UI State machine.
I want to show a wait screen when a long running command is invoked by a user using a button on the current form. I believe I can use the asynchronous option when linking the command on the button. I have setup a form in which I have a button which should invoke the asynchronous command. In command selection for that button, I have set the action to show the wait screen form and have marked the command as asynchronous. However when I use the asynchronous option, the code shows the wait screen, but after that it throws a NullPointerException.
As per my understanding, once you mark a command as asynchronous, it will call the following methods from a different thread where you can handle its processing.
protected void asyncCommandProcess(Command cmd, ActionEvent sourceEvent);
protected void postAsyncCommand(Command cmd, ActionEvent sourceEvent);
However this methods are not getting called and it throws a NullPointerException.
When I looked at the LWUIT code, in UIBuilder.java(lineno. 2278), I see that it constructs the new thread for an asynchronous command as follows:
new Thread(new FormListener(currentAction, currentActionEvent, f)).start();
But when running it through Debugger I see that currentAction and currentActionEvent are always null. And hence when the FormListener thread starts running, it never calls the above two async command processing methods. Please see the listing of the run() method in the UIBuilder.java(line no. 2178)
public void run() {
if(currentAction != null) {
if(Display.getInstance().isEdt()) {
postAsyncCommand(currentAction, currentActionEvent);
} else {
asyncCommandProcess(currentAction, currentActionEvent);
// wait for the destination form to appear before moving back into the LWUIT thread
waitForForm(destForm);
}
} else {
if(Display.getInstance().isEdt()) {
if(Display.getInstance().getCurrent() != null) {
exitForm(Display.getInstance().getCurrent());
}
Form f = (Form)createContainer(fetchResourceFile(), nextForm);
beforeShow(f);
f.show();
postShow(f);
} else {
if(processBackground(destForm)) {
waitForForm(destForm);
}
}
}
}
In the above method, since the currentAction is null, it always goes into the else statement and since the nextForm is also null, it causes the NullPointerException.
On further look at the UIBuilder.java code, I noticed what is causing the NullPointer exception. It seems when the FormListner is created, it is passed currentAction and currentActionEvent, however they are null at that time. Instead the code should be changed as follows(starting at line 2264):
if(action.startsWith("#")) {
action = action.substring(1);
Form currentForm = Display.getInstance().getCurrent();
if(currentForm != null) {
exitForm(currentForm);
}
Form f = (Form)createContainer(fetchResourceFile(), action);
beforeShow(f);
/* Replace following with next lines for fixing asynchronous command
if(Display.getInstance().getCurrent().getBackCommand() == cmd) {
f.showBack();
} else {
f.show();
}
postShow(f);
new Thread(new FormListener(currentAction, currentActionEvent, f)).start();
*/
new Thread(new FormListener(cmd, evt, f)).start();
return;
}
Can lwuit development team take a look at the above code, review and fix it. After I made the above change, the asynchronous command processing methods were invoked.
Thank you.
Thanks for the information, its probably better to use the issue tracker for things like this (at http://lwuit.java.net).
I will make a similar change although I don't understand why you commented out the form navigation portion.
To solve your use case of a wait screen we have a much simpler solution: Next Form. Just show the wait screen and in it define the "Next Form" property.
This will trigger a background thread to be invoked (processBackground callback) and only when the background thread completes the next form will be shown.
So I was writing a quick application to sort my wallpapers neatly into folders according to aspect ratio. Everything is going smoothly until I try to actually move the files (using FileInfo.MoveTo()). The application throws an exception:
System.IO.IOException
The process cannot access the file because it is being used by another process.
The only problem is, there is no other process running on my computer that has that particular file open. I thought perhaps that because of the way I was using the file, perhaps some internal system subroutine on a different thread or something has the file open when I try to move it. Sure enough, a few lines above that, I set a property that calls an event that opens the file for reading. I'm assuming at least some of that happens asynchronously. Is there anyway to make it run synchronously? I must change that property or rewrite much of the code.
Here are some relevant bits of code, please forgive the crappy Visual C# default names for things, this isn't really a release quality piece of software yet:
private void button1_Click(object sender, EventArgs e)
{
for (uint i = 0; i < filebox.Items.Count; i++)
{
if (!filebox.GetItemChecked((int)i)) continue;
//This calls the selectedIndexChanged event to change the 'selectedImg' variable
filebox.SelectedIndex = (int)i;
if (selectedImg == null) continue;
Size imgAspect = getImgAspect(selectedImg);
//This is gonna be hella hardcoded for now
//In the future this should be changed to be generic
//and use some kind of setting schema to determine
//the sort/filter results
FileInfo file = ((FileInfo)filebox.SelectedItem);
if (imgAspect.Width == 8 && imgAspect.Height == 5)
{
finalOut = outPath + "\\8x5\\" + file.Name;
}
else if (imgAspect.Width == 5 && imgAspect.Height == 4)
{
finalOut = outPath + "\\5x4\\" + file.Name;
}
else
{
finalOut = outPath + "\\Other\\" + file.Name;
}
//Me trying to tell C# to close the file
selectedImg.Dispose();
previewer.Image = null;
//This is where the exception is thrown
file.MoveTo(finalOut);
}
}
//The suspected event handler
private void filebox_SelectedIndexChanged(object sender, EventArgs e)
{
FileInfo selected;
if (filebox.SelectedIndex >= filebox.Items.Count || filebox.SelectedIndex < 0) return;
selected = (FileInfo)filebox.Items[filebox.SelectedIndex];
try
{
//The suspected line of code
selectedImg = new Bitmap((Stream)selected.OpenRead());
}
catch (Exception) { selectedImg = null; }
if (selectedImg != null)
previewer.Image = ResizeImage(selectedImg, previewer.Size);
else
previewer.Image = null;
}
I have a long-fix in mind (that's probably more efficient anyway) but it presents more problems still :/
Any help would be greatly appreciated.
Since you are using your selectedImg as a Class scoped variable it is keeping a lock on the File while the Bitmap is open. I would use an using statement and then Clone the Bitmap into the variable you are using this will release the lock that Bitmap is keeping on the file.
Something like this.
using ( Bitmap img = new Bitmap((Stream)selected.OpenRead()))
{
selectedImg = (Bitmap)img.Clone();
}
New answer:
I looked at the line where you do an OpenRead(). Clearly, this locks your file. It would be better to provide the file path instead of an stream, because you can't dispose your stream since bitmap would become erroneous.
Another thing I'm looking in your code which could be a bad practice is binding to FileInfo. Better create a data-transfer object/value object and bind to a collection of this type - some object which has the properties you need to show in your control -. That would help in order to avoid file locks.
In the other hand, you can do some trick: why don't you show streched to screen resolution images compressing them so image size would be extremly lower than actual ones and you provide a button called "Show in HQ"? That should solve the problem of preloading HD images. When the user clicks "Show in HQ" button, loads that image in memory, and when this is closed, it gets disposed.
It's ok for you?
If I'm not wrong, FileInfo doesn't block any file. You're not opening it but reading its metadata.
In the other hand, if you application shows images, you should move to memory visible ones and load them to your form from a memory stream.
That's reasonable because you can open a file stream, read its bytes and move them to a memory stream, leaving the lock against that file.
NOTE: This solution is fine for not so large images... Let me know if you're working with HD images.
using(selectedImg = new Bitmap((Stream)selected))
Will that do it?