e805. listening for value changes in a jprogressbar component.txt

来自「这里面包含了一百多个JAVA源文件」· 文本 代码 · 共 21 行

Whenever the value of a progress bar is changed, a change event is fired. In fact, the event is also fired when the minimum or maximum values are changed. However, the event does not specify which values were changed. 
    // Create a horizontal progress bar
    int minimum = 0;
    int maximum = 100;
    JProgressBar progress = new JProgressBar(minimum, maximum);
    
    progress.addChangeListener(new ChangeListener() {
        // This method is called when the value, minimum, or maximum is changed.
        public void stateChanged(ChangeEvent evt) {
            JProgressBar comp = (JProgressBar)evt.getSource();
    
            // The old value is not available
    
            // Get new values
            int value = comp.getValue();
            int min = comp.getMinimum();
            int max = comp.getMaximum();
        }
    });