Question

我正在使用QProgress来显示读取配置文件的状态。我有一个向主窗口发送信号以显示状态的类。当前，我可以显示状态，但立即显示100％，我希望它更加可靠。就像我看到的那样，它从例如0到5到20到45等不断发展，直到达到100％。这是我到目前为止所用餐的食物：

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new 
Ui::MainWindow)
{
    connect(sampleClass, SIGNAL(onDisplayStatus(int)), this, 
    SLOT(onDisplayStatus(int)));

    // OtherClass instance
    // config file has lots of fields to be read
    otherClass->validateConfigfile();
}

MainWindow::onDisplayStatus(int status)
{
    ui->ProgressStatus.setValue(status);
}

SampleClass::displayStatus(int value)
{
    emit onDisplayStatus(value);
}

// This will validate if the config file is valid or existing; the 
// progress will be set to 10 if valid and existing
OtherClass::validateConfigfile() 
{
    // instance of SampleClass
    //10 is the value of progress. 
    //I dont want it to be fixed. Pleas suggest how to properly compute 
    //the value
    sampleClassInstance->displayStatus(10); 

    loadSection1();
    loadSection2();
}

OtherClass::loadSection1()
{
    // load section 1 here
    sampleClassInstance->displayStatus(20);
}

OtherClass::loadSection2()
{
    // load section 2 here
    sampleClassInstance->displayStatus(35);
}

注意：我的配置文件包含许多字段。下面是示例：

[Section 1]
S1Field1 = 0
S1Field2 = 1
S1Field3 = 2

[Section 2]
S2Field1 = 0
S2Field2 = 1

[Section 3]
S3Field1 = 0
S3Field2 = 1
S3Field3 = 2
S3Field4 = 6
S3Field5 = 4
S3Field6 = 9

以此类推...

我在OtherClass内部创建了一个方法，该方法将读取每个部分和字段。读取每个部分后，将显示进度值，直到进度达到100。

Answer 1

请查看文档：{{3}}

您必须设置进度条的最大值和最小值。

Answer 2

如果您在主线程（Qt GUI的线程）中进行处理，则直到完成后您的小部件才会被更新/重新绘制，然后直接显示100％。

为了正确使用进度条，您需要在其他进程中处理一些代码或异步代码。

PS：您也可以将您的工作者类信号直接连接到进度条插槽，不需要private static final int BINARY = 2; // probably use enum private static final int OCTAL = 8; // probably use enum private static final int DECIMAL = 10; // probably use enum private JTextField textField; private JButton n1, n2, n3, n4, n5, n6, n7, n8, n9, n0, add, subtract, multiply, divide, clear, backspace, bin, dec, oct, hex; private JPanel panel, panel1, p; private int system = DECIMAL; // initialization code public void actionPerformed(ActionEvent event) { if(event.getSource() == bin){ system = BINARY; } else if (event.getSource() == dec) { system = DECIMAL; } // same for other systems. if (system == BINARY) { if(event.getSource() == n1){ textField.setText(textField.getText() + "1"); } else if(event.getSource() == n0){ textField.setText(textField.getText() + "0"); } else if(event.getSource() == add){ textField.setText(textField.getText() + " + "); } else if(event.getSource() == subtract){ textField.setText(textField.getText() + " - "); } else if(event.getSource() == multiply){ textField.setText(textField.getText() + " * "); } else if(event.getSource() == divide){ textField.setText(textField.getText() + " / "); } else if(event.getSource() == clear){ textField.setText(""); } } else if (system == DECIMAL) { if(event.getSource() == n1){ textField.setText(textField.getText() + "1"); } else if(event.getSource() == n2){ textField.setText(textField.getText() + "2"); } else if(event.getSource() == n3){ textField.setText(textField.getText() + "3"); } else if(event.getSource() == n4){ textField.setText(textField.getText() + "4"); } else if(event.getSource() == n5){ textField.setText(textField.getText() + "5"); } else if(event.getSource() == n6){ textField.setText(textField.getText() + "6"); } else if(event.getSource() == n7){ textField.setText(textField.getText() + "7"); } else if(event.getSource() == n8){ textField.setText(textField.getText() + "8"); } else if(event.getSource() == n9){ textField.setText(textField.getText() + "9"); } else if(event.getSource() == n0){ textField.setText(textField.getText() + "0"); } else if(event.getSource() == add){ textField.setText(textField.getText() + " + "); } else if(event.getSource() == subtract){ textField.setText(textField.getText() + " - "); } else if(event.getSource() == multiply){ textField.setText(textField.getText() + " * "); } else if(event.getSource() == divide){ textField.setText(textField.getText() + " / "); } else if(event.getSource() == clear){ textField.setText(""); } } // same for other systems }。

Answer 3

您首先必须在读取文件时计算进度。也许Most efficient way of creating a progress bar while reading input from a file可以为您提供帮助。

然后，您必须将进度报告给QProgressBar。为此，您的文件读取方法需要接收进度指示器作为函数参数，并调用其状态显示方法。如果不想显式依赖Qt，则可能要创建一个纯抽象的ProgressIndicator接口类，使文件读取方法使用这样的ProgressIndicator，然后创建一个继承自Qt的类。 ProgressIndicator和QProgressBar，并将接口方法连接到QProgressBar中的实现。

在QProgressBar中显示进度

3 个答案: