Could not parse stylesheet of object QLabel
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@JonB said in Could not parse stylesheet of object QLabel:
@oBOXPOH
I assume you know how to write signals & slots already. If not, look at @Christian-Ehrlicher's link.Define a signal in the thread.
emitthe signal from the thread, with whatever parameters are desired. Define a slot in the main UI thread. In the UIconnect()the thread's signal to the UI's slot. There act on the signal and its parameters to execute thepLabel->setStyleSheet().As @Christian-Ehrlicher said, whether you need or should have any non-UI thread is another question. Most newcomers seem to think they need threads, when they do not.
Ok. But where can I find the main UI thread? Just I created slot for changing in MainWindow.cpp - and I still have my problem...
Let me explain, what I have. I have MainWindow class, where I create 2 widgets. In the second widget I have some another widgets. When I activate button of the first widget, I start the thread, where I get requests to change some properties of widgets in second widget. For example, I can change text for labels, but can't change styles of labels.
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@oBOXPOH said in Could not parse stylesheet of object QLabel:
I start the thread
But do you really need the thread? You dont need an extra thread just to change widget properties
@Pl45m4 said in Could not parse stylesheet of object QLabel:
@oBOXPOH said in Could not parse stylesheet of object QLabel:
I start the thread
But do you really need the thread? You dont need an extra thread just to change widget properties
I think, I need the thread, because I use QSerialPort to send and read messages. If I won't use the thread, I will block the widget, where I create the thread.
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@Pl45m4 said in Could not parse stylesheet of object QLabel:
@oBOXPOH said in Could not parse stylesheet of object QLabel:
I start the thread
But do you really need the thread? You dont need an extra thread just to change widget properties
I think, I need the thread, because I use QSerialPort to send and read messages. If I won't use the thread, I will block the widget, where I create the thread.
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@oBOXPOH
No, Qt classes like serial ports are asynchronous. So long as you use the signals/slots, not blocking calls. It seems unlikely you need a secondary thread, and without multiple threads your life will be much easier....If you are currently using the blocking
QSerialPortapproach (withwaitFor...()), have a look at the non-blocking example:
If debugging is the process of removing software bugs, then programming must be the process of putting them in.
~E. W. Dijkstra
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If you are currently using the blocking
QSerialPortapproach (withwaitFor...()), have a look at the non-blocking example:@Pl45m4 said in Could not parse stylesheet of object QLabel:
@JonB said in Could not parse stylesheet of object QLabel:
serial ports are asynchronous
Not always. There is a blocking and non-blocking QSerialPort appraoch.
I'm not following you? I wrote
No, Qt classes like serial ports are asynchronous. So long as you use the signals/slots, not blocking calls.
The calls are asynchronous. If you choose to
waitFor..()you are choosing to block, by making your code synchronous. What are you saying any different from that? -
@oBOXPOH
I assume you know how to write signals & slots already. If not, look at @Christian-Ehrlicher's link.Define a signal in the thread.
emitthe signal from the thread, with whatever parameters are desired. Define a slot in the main UI thread. In the UIconnect()the thread's signal to the UI's slot. There act on the signal and its parameters to execute thepLabel->setStyleSheet().As @Christian-Ehrlicher said, whether you need or should have any non-UI thread is another question. Most newcomers seem to think they need threads, when they do not.
@JonB said in Could not parse stylesheet of object QLabel:
@oBOXPOH
I assume you know how to write signals & slots already. If not, look at @Christian-Ehrlicher's link.Define a signal in the thread.
emitthe signal from the thread, with whatever parameters are desired. Define a slot in the main UI thread. In the UIconnect()the thread's signal to the UI's slot. There act on the signal and its parameters to execute thepLabel->setStyleSheet().As @Christian-Ehrlicher said, whether you need or should have any non-UI thread is another question. Most newcomers seem to think they need threads, when they do not.
I can't to win my problem with styleSheet... I even deleted thread. Let me explain what I have done.
When I click to button1_1, I emit some signal from widget1 to slot of widget2. In slot of widget2 I emit some signal to slot of created some class inside widget2. Inside this class I have a loop with signals/slots. And during this loop I need to change styles of widgets inside widget2 (label2_1). When I need to change style of label, I emit signal from class to slot of widget2 and call method of, for example, widget2_1 in order to change the style of label, but, without exception, I get "Could not parse stylesheet of object QLabel(0xf66ad8)". I tried many things, but still no success.Hope for your help! Thank you in advance!
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@JonB said in Could not parse stylesheet of object QLabel:
@oBOXPOH
I assume you know how to write signals & slots already. If not, look at @Christian-Ehrlicher's link.Define a signal in the thread.
emitthe signal from the thread, with whatever parameters are desired. Define a slot in the main UI thread. In the UIconnect()the thread's signal to the UI's slot. There act on the signal and its parameters to execute thepLabel->setStyleSheet().As @Christian-Ehrlicher said, whether you need or should have any non-UI thread is another question. Most newcomers seem to think they need threads, when they do not.
I can't to win my problem with styleSheet... I even deleted thread. Let me explain what I have done.
When I click to button1_1, I emit some signal from widget1 to slot of widget2. In slot of widget2 I emit some signal to slot of created some class inside widget2. Inside this class I have a loop with signals/slots. And during this loop I need to change styles of widgets inside widget2 (label2_1). When I need to change style of label, I emit signal from class to slot of widget2 and call method of, for example, widget2_1 in order to change the style of label, but, without exception, I get "Could not parse stylesheet of object QLabel(0xf66ad8)". I tried many things, but still no success.Hope for your help! Thank you in advance!
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Hi
can you show the complete stylesheet?
as that errors says it cannot be parsed so it might just be a case of invalid syntax.@mrjj said in Could not parse stylesheet of object QLabel:
Hi
can you show the complete stylesheet?
as that errors says it cannot be parsed so it might just be a case of invalid syntax.pLabel->setStyleSheet(QString(pCChar_GreenStatusStyle));const char *pCChar_GreenStatusStyle = "{ color: green; font-weight: bold; }"; -
Hi
can you show the complete stylesheet?
as that errors says it cannot be parsed so it might just be a case of invalid syntax.@mrjj said in Could not parse stylesheet of object QLabel:
Hi
can you show the complete stylesheet?
as that errors says it cannot be parsed so it might just be a case of invalid syntax.You are right, by the way! I need:
const char* *pCChar_GreenStatusStyle = "QLabel { color: green; font-weight: bold; }";
And now it works finally! By the way, I deleted this QLabel word because I tried to find an error.
Anyway, If someone has such problem, try to use only signals and slots like I used (image and description above) and check your styles. For serialPorts, for example, don't use threads, because else you will be in trouble.
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@mrjj said in Could not parse stylesheet of object QLabel:
Hi
can you show the complete stylesheet?
as that errors says it cannot be parsed so it might just be a case of invalid syntax.You are right, by the way! I need:
const char* *pCChar_GreenStatusStyle = "QLabel { color: green; font-weight: bold; }";
And now it works finally! By the way, I deleted this QLabel word because I tried to find an error.
Anyway, If someone has such problem, try to use only signals and slots like I used (image and description above) and check your styles. For serialPorts, for example, don't use threads, because else you will be in trouble.
@oBOXPOH said in Could not parse stylesheet of object QLabel:
I need:
const char* *pCChar_GreenStatusStyle = "QLabel { color: green; font-weight: bold; }";I am surprised at this! That is a
char **. But if you say that is required to work.....
