A few questoins about Qt

1 By default, that's not a minimize button in the Qt widget in windows, but a help ("?" symbol) button. If I want to add a minimize button for a dialog at the same remove the help symbol. What I should do.

2 Why I write a file in the patten in a console window:
QFile file("C:\abc\test.txt");
it doesn,t work. But it work in this way : QFile file("C:\\abc\\test.txt"); At the same time, I get the file name from QFileDialog::getOpenFileName and do not need to replace '\' with "\\". and it work fine. Why?

3 My code fragment is showed as the following:

Code:

---

if(cloudCheckBox->checkState()==Qt::Checked);
  	{
  	  for(size_t i=9;i<17;++i)
  	  {
  	    trimCloud(list[i]);	
  	  } 	
  	}

---

It's strange that even I do not click the CheckBox, but it still execute the above code fragment. I try cloudCheckBox->isChecked() instead, I got the same result. Why?

By the way, in the constructor function, I set the CheckBox true.

Code:

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cloudCheckBox->setChecked(true);
  windSpeedCheckBox->setChecked(true);

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When i run the app, I click to remove the "√".



4 From my perspective, I do think that try my thinking in a console window is very useful. Also because that I don't know how to test my code in a GUI program, it's very trival.
How do you solve this problem?

Thanks! Any relpy is appreciated!

Quote:

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Originally Posted by HelloDan

1 By default, that's not a minimize button in the Qt widget in windows, but a help ("?" symbol) button. If I want to add a minimize button for a dialog at the same remove the help symbol. What I should do.

---

Qt::WindowFlags

Quote:

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2 Why I write a file in the patten in a console window:
QFile file("C:\abc\test.txt");
it doesn,t work. But it work in this way : QFile file("C:\\abc\\test.txt"); At the same time, I get the file name from QFileDialog::getOpenFileName and do not need to replace '\' with "\\". and it work fine. Why?

---

escaping?

Quote:

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Originally Posted by HelloDan

3 My code fragment is showed as the following:

Code:

---

if(cloudCheckBox->checkState()==Qt::Checked);
  	{
  	  for(size_t i=9;i<17;++i)
  	  {
  	    trimCloud(list[i]);	
  	  } 	
  	}

---

It's strange that even I do not click the CheckBox, but it still execute the above code fragment. I try cloudCheckBox->isChecked() instead, I got the same result. Why?

---

checkState() is a state not an action. If you want react on user actions use signal and slots. (By the way, maybe you want use QAbstractButton::isChecked().)

Quote:

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4 From my perspective, I do think that try my thinking in a console window is very useful. Also because that I don't know how to test my code in a GUI program, it's very trival.
How do you solve this problem?

---

I don't understand the question. For debugging a GUI use gdb or simple qDebug().

qDebug().

How to use qDebug()? I try it in the console window, it's OK. But I try in a GUI program, I can see nothing.

Add CONFIG+=console to your project file and rerun qmake.

I don't know how to correct the cloudCheckBox->checkState()==Qt::Checked problem.
Can anyone give some tips?

What do you want achieve? And when do you call the function which is checking the state of the box?

I'm sorry. My English is really very limited.

What i want to achive is that if the cloudCheckBox has a "√" (it's checked.), then execute the code. otherwise, do nothing.

but the following code line seem that it always true, even i remove the "√"
if(cloudCheckBox->isChecked());

Why? how to solve the problem. Thanks!

your constructor:

Code:

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QObject::connect(cloudCheckBox, SIGNAL(toggled(bool)), this, SLOT(yourSlot(bool));

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and then

Code:

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void YourClass::yourSlot(bool checked)
{
    if (checked) {
       // do what ever you want
    }
}

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if(cloudCheckBox->checkState()==Qt::Checked);


Thank! It's a very stupid mistake. remove ; will be ok