I'm writing simple pomodoro application, which is basically countdown timer. Right now, I've got countdown working, but the weird thing is that when I add another attribute to my class (arbitrary), I get Sedmentation fault error.
Using gdb, the problem should be here:
void Status::showPomodoroTime() {
QTime time = pomodoroTime->addSecs(elapsed);
activeTime->display(time.toString("mm:ss"));
}
where activeTime is QLCDNumber widget and elapsed is int.
More context:
void Status::createDefaultIntervals()
{
pomodoroInterval = new QTime(0, 25);
pomodoroBreak = new QTime(0, 5);
pomodoroLongBreak = new QTime(0, 15);
}
void Status::run()
{
if (pomodoroActive == STOP) {
pomodoroTime = pomodoroInterval;
showPomodoroTime();
}
pomodoroActive = RUN;
updateStatusArea();
timerTick();
}
CreateDefaultInterval definitely runs before showPomodoroTime.
What bugs me, that whole application works fine. Just when I add another attribute, it starts to throw sedfault.
How can variable declaration in *.h file cause segfault in *.cpp?
If you want more code, I can put it anywhere. I just don't know, what place is persistent enough. Don't want to post it here (about 300 lines of code).
check if(pomodoro!= NULL) and then do addSecs().
pomodoroTime is probably uninitialized or deleted
Related
Using Cocos2d-x and C++, I'm trying to play and pause an animation for a sprite.
I'm using version 3.15.1 of Cocos2dx.
I have a class called PlayerSprite which is derrived from the cocos2d::Sprite class. Inside PlayerSprite initialization, I've setup my animation with the following code:
SpriteBatchNode* playerSpriteBatch = SpriteBatchNode::create("player.png");
SpriteFrameCache* spriteFrameCache = SpriteFrameCache::getInstance();
spriteFrameCache->addSpriteFramesWithFile("player.plist");
Vector<SpriteFrame*> animFrames(2);
char str[18] = { 0 };
for (int i = 1; i < 3; i++) {
sprintf(str, "player_idle_%d.png", i);
SpriteFrame* frame = spriteFrameCache->getSpriteFrameByName(str);
animFrames.pushBack(frame);
}
Animation* idleAnim = Animation::createWithSpriteFrames(animFrames, 0.8f);
self->idleAction = self->runAction(RepeatForever::create(Animate::create(idleAnim)));
self->idleAction->setTag(0);
When I run the code, it works fine and the animation loops correctly.
In my void update() method, I am trying to pause/play the action/animation based of weather the player is moving or idle.
I do this with the following code:
const bool isIdleActionRunning = this->getNumberOfRunningActionsByTag(0) > 0 ? true : false;
const bool isMoving = !vel.isZero();
if (!isMoving && !isIdleActionRunning) {
// Player is idle AND animation is not running
// Run animation
this->runAction(idleAction);
} else if (isMoving && isIdleActionRunning) {
// Player is moving but animation is running
// Pause animation
this->stopActionByTag(0);
}
When I run this code now, my character falls, and as soon as he hits the gound, I get an error at this->runAction(idleAction); saying:
Access violation reading location 0xDDDDDDE5
I believe this is caused due to this->stopActionByTag(0) deleting the action pointer. I've tried to clone the action to avoid this but have had no success.
I know this is a bit late and you might already have solved this but here goes...
Your problem is that you cannot use one instance of Action (idleAction) multiple times. So, once you have run it and removed it, it is released and cannot be used. So, you have 2 options now,
Either create a new idleAction Action every time before running the action.
Or, have an idleAction retained and don't run it ever. Instead, create a clone of this idleAction and run a new clone each time. i.e.
idleAction->retain();
const bool isIdleActionRunning = this->getNumberOfRunningActionsByTag(0) > 0 ? true : false;
const bool isMoving = !vel.isZero();
if (!isMoving && !isIdleActionRunning) {
// Player is idle AND animation is not running
// Run animation
Action idleActionClone = idleAction->clone();
this->runAction(idleActionClone);
} else if (isMoving && isIdleActionRunning) {
// Player is moving but animation is running
// Pause animation
this->stopActionByTag(0);
}
Solution: call retain() to keep your action.
It's a matter of memory management of cocos2d-x.
In create() function of your RepeatForever class (derived from Ref), the reference count is set to 1 and there is a line of code ret->autorelease() before returning the object, which means this object will be released automatically at the end of this frame.
You called runAction() function the same frame you created it, the action is retained by ActionManager, it's reference count set to 2, and then 1 at the end of the frame (autorelease).
After your stopping it, it's released by ActionManager, reference count set to 0 and it's deleted. After this you use your action, it will be an access violation method.
*Edit: don't forget to release the action manually when PlayerSprite is deleted, or it's a leak.
When you stop action it's being recycled from memory. In order to play action once more, you have to recreate it. So you may just make a creator function, which returns your animation. The downside is you're recreating animation each time and it'll also play from the beginning (technically you can rewind it).
But I've developed a simpler technique to pause/resume animations:
Let's say you have an action:
action = MoveBy::create(5.0f, Vec2(50, 100));
Now, you can embed this action into Speed action like this:
action = Speed::create(MoveBy::create(5.0f, Vec2(50, 100)), 1.0f);
1.0f - is speed, so it's normal action rate. Now to pause just call:
action->setSpeed(0.0f);
and to resume:
action->setSpeed(1.0f);
you can also use different speed if you need it for some reason or another ;)
I'm making a thread software with VTK, where I need to change the model itself in real time, while I need to change his method of rendering. Everything is working fine, but, the problem start with the interactor->start(); , the model data gets updated just fine, but it's only showed on screen when I move The camera. Also I have selected some methods for generating a 3D data from a imagedata file, for that I need to close the vtk window (interactor window) and then the code will reopen it and send the new data generated to it...
I would need something like these:
int force close_window = false; int refresh_interactor = false;
I managed to make the Window close, but only with vtkcommand::Keypressed command, but idk how do I do with a new command :S, I tried the vtkcommand::UserEvent but I didn't found a good information about how to deal with that data (like some way to call it)
the way I'm dealing with VTK is with two threads, the first one, is just about the vtk iren loop, and the second one would manage the models and check if iren requires to be updated.
In my dream code it should be something like this:
=======================================================
bool VTKWindow()
{
...
vtkSmartPointer ator = vtkSmartPointer::New();
iren = vtkSmartPointer::New();
RenWindow = vtkSmartPointer::New();
render->SetBackground(.1, .2, .3);
RenWindow->AddRenderer(renderer);
iren->SetRenderWindow(RenWindow);
if(data_type == voxel_type)
{
Render->AddViewProp(VoxelData);
}
else
{
actor->SetMapper(PolyData);
Render->AddActor(Actor);
}
RenWindow->Render();
iren->Start();
}
void ManageVTK()
{
while true loop...
if(force close_window == true)
do some command to exit the iren loop
if(refresh_interactor == true)
do some command to refresh iren
}
Sorry for the english, it's not my native language, and also sorry about the question format, it's the first time I'm using stackoverflow
It may sounds stupid, but, I found a kind of solution for the problem.
I saw on related links this guy vtkRenderWindowInteractor event loop and threading and, it's almost the same problem...
class VTKNewEvent : public vtkCommand{
public:
vtkTypeMacro(VTKNewEvent , vtkCommand);
static VTKNewEvent * New(){
return new VTKNewEvent ;
}
void Execute(vtkObject * caller, unsigned long vtkNotUsed(eventId), void * vtkNotUsed(callData)){
vtkRenderWindowInteractor *iren = static_cast<vtkRenderWindowInteractor*>(caller);
if (iren_close == true){
iren->GetRenderWindow()->Finalize // Stop the interactor
iren->TerminateApp();
iren_close = false;
}
if (iren_update== true){
renderJanela->Render();
iren_update= false;
}
}
};
bool VTKWindow(){
vtkSmartPointer<VTKNewEvent > IrenRefresh= vtkSmartPointer<VTKNewEvent>::New();
...
iren->CreateRepeatingTimer(1);//this makes that IrenRefresh will be called at every 1ms
iren->AddObserver(vtkCommand::TimerEvent, IrenRefresh);
iren->Start();
...
}
it's simple, but, maybe not the best, but it did Th job, I hope this link will help people that are starting into the VTK world, since threads + rendering loop wasn't a simple job to understand what was going on
In my project, I have a listWidget. When the user clicks an item in the list, it loads this:
void BlockSelect::on_blockList_clicked(const QModelIndex &index)
{
QString blockListName;
QString temp_hex;
QString temp_hex2;
int temp_int;
QListWidgetItem *newitem = ui->blockList->currentItem();
blockListName = newitem->text();
temp_hex = blockListName.mid(0, blockListName.indexOf(" "));
if(temp_hex.indexOf(":") == -1)
{
temp_int = temp_hex.toInt();
ui->blockIdIn->setValue(temp_int);
ui->damageIdIn = 0;
}
else
{
temp_hex2 = temp_hex.mid(temp_hex.indexOf(":")+1, temp_hex.length()-(temp_hex.indexOf(":")+1));
temp_hex = temp_hex.mid(0, temp_hex.indexOf(":"));
temp_int = temp_hex.toInt();
ui->blockIdIn->setValue(temp_int);
temp_int = temp_hex2.toInt();
ui->damageIdIn->setValue(temp_int);
}
}
Most of this is just string manipulation. (You don't have need to study this syntax or anything)
My problem is, when the user clicks on another list item quickly (Before this current process is finished) the program crashes. Is there any way to allow fast clicks (multiple processes at once) or maybe an alternative solution?
Thanks for your time :)
I hope that you execute all this code in the GUI thread. If so, then there will be no problem - if your code were correct (it isn't). There is no such thing as the "process" that you mention in your question. The clicks are handled by a slot, and they are invoked from an event handler within the list. This is not supposed to crash, and the clicks will be handled in a serialized fashion - one after another.
Here's the bug: Why do you reset the value of an allocated UI pointer element to zero?
ui->damageIdIn = 0;
This is nonsense. Maybe you mean to ui->damageIdIn->setValue(0) or ui->damageIdIn->hide(). You then proceed to use this zero value in
ui->damageIdIn->setValue(temp_int);
and it crashes.
You may also have bugs in other places in your code.
I am quite new to C++ and Qt. I've gotten pretty far on my current project, but I've been putting off this one part. I have a pushbutton that opens a new dialog like this:
void MainWindow::on_fillAll_clicked()
{
int yo;
BlockSelect bSelect;
bSelect.setModal(true);
bSelect.exec();
if( bSelect.exec() == QDialog::Accepted )
{
//Get stuff here?
//I want to fill yo with the spinbox value
yo = bSelect.stuff();
return;
}
qDebug() << yo;
}
This works fine. In the dialog I have a spin box. I want to send that value inputted to the spin box to my main window when the user clicks OK.
I have been trying to get "int yo;" to have that value from the spinbox but everything I try just gets an error.
I added this to my BlockSelect public class:
int stuff();
And I made this function in my blockselect.cpp:
int BlockSelect::stuff()
{
qDebug() << "The function was called";
return ui->yolo->value();
}
But qDebug never shows anything???
So how can I fill yo from the main window with yolo from the dialog?
Sorry if I didn't explain this well :( I'm still learning.
Thanks for your time :)
First of all, there is no need to call exec() twice, just use it once within the if statement.
To answer your question, you still have the bSelect dialog object (and I'm assuming BlockSelect is a class you define?), so make an accessor function inside it to retrieve the values you want.
if( bSelect.exec() == QDialog::Accepted )
{
//Get stuff here?
//I want to fill yo with the spinbox value
yo = bSelect.stuff();
return;
}
EDIT:
Your BlockSelect class needs to contain an accessor function, this means a function that returns a value.
int stuff() { return ui->yolo->value();}
What I'm doing here is retrieving the spinbox's value (assuming it is named 'yolo') and returning it as a result of calling the 'stuff' function.
I'm trying to have animation on a button click event. But somehow the animation is not working. I have referred the Qt reference docs, but could not find the root cause which is causing the issue
Below is sample code :
void MainWindow::AnimationClick()
{
// define toolbar y movement positions for animation
TOOLBAR_Y_SHOWN = 0;
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
m_AnimatedWidget = new AnimatedWidget(this);
QPropertyAnimation *m_ani = new QPropertyAnimation(m_AnimatedWidget, "pos", this);
m_ani->setDuration(500);
m_ani->setEndValue(QPoint(m_AnimatedWidget->pos().x(), TOOLBAR_Y_HIDDEN));
m_ani->setEasingCurve(QEasingCurve::InBack);
m_ani->start();
}
With the above implementation nothing is happening on the click event.
Any suggestions , Thanks.
This looks wrong:
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
m_AnimatedWidget = new AnimatedWidget(this);
First you access m_AnimatedWidget then you allocate it?
When you get a crash, such as segmentation fault, always run your program in a debugger. It would have helped you find this error quite easy as it would have stopped on the line of the error.
m_ani->setDuration(500);
setDuration() argument is expressed in milliseconds. You should probably put more than half a second when you are testing.
I got it. I was not allowing the m_AnimatedWidget to show upon the screen.
Below is the edited snippet.
void MainWindow::AnimationClick()
{
// define toolbar y movement positions for animation
TOOLBAR_Y_SHOWN = 0;
m_AnimatedWidget = new AnimatedWidget(this);
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
QPropertyAnimation *m_ani = new QPropertyAnimation(m_AnimatedWidget, "pos", this);
m_ani->setDuration(5000);
m_ani->setEndValue(QPoint(m_AnimatedWidget->pos().x(), TOOLBAR_Y_HIDDEN));
m_ani->setEasingCurve(QEasingCurve::InBack);
m_ani->start();
m_AnimatedWidget->show();
}