Term
| In order to draw things on a component what do you need to do? |
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Definition
Define a class that extends JPanel
and overrides its paintComponent method. |
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Term
| How do you override a paintComponent method? |
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Definition
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Term
| What are the first 3 lines in drawing a polygon? |
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Definition
Polygon polygon = new Polygon();
polygon.addPoint(x, y);
g.drawPolygon(polygon) |
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Term
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Definition
| drawArc(int x, int y, int h, int angle1, int angle2); |
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Term
| What kind of class is FontMetrics? |
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Definition
|
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Term
| How do you get a fontMetrics object for a specific font? |
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Definition
| getFontMetrics methods defined in the graphics class. |
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Term
| How do you create an image icon and display it in a label? |
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Definition
ImageIcon icon = new ImageIcon("image/us.gif");
Jlabel jlblImage = new JLabel(icon); |
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Term
| To make an image a flexible size what class do you use? |
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Definition
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Term
| What is the difference between displaying images in a JLabel and in a JPanel? |
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Definition
| An image displayed on a label is not flexible, but an image displayed on a panel is stretchable. |
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Term
| Draw a thick line from (10,10) to (70, 30). You can draw several lines next to each other to create the effect of one thick line. |
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Definition
for (int i = 0; i < 10, i++)
g.drawLine(10, 10 + i, 70, 30 +i) |
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Term
| Can you draw things on any Swing GUI component? Why should you use a panel as a canvas for drawings rather than a label or a button? |
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Definition
| Yes, you should declare a canvas by subclassing JPanel because it is made to display things. where as labels are more for buttons. |
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Term
| What is an event defined as? |
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Definition
| a signal sent to a program saying that something has happened. |
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Term
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Definition
| Mouse movements, mouse clicks, keystrokes, or by the operating system, such as a timer. |
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Term
| How do you identify the source object of the event? |
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Definition
| getSource() instance method in the EventObject class. |
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Term
| What are examples of subclasses of EventObject? |
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Definition
| button actions, window events, component events, mouse movements, keystrokes. |
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Term
| What does a listener class do? |
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Definition
| Create a listener object for a GUI component (eg., a button). |
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Term
| Where do you define the listener class? |
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Definition
| inside of the frame class |
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Term
| Can a listener class be shared by other applications? |
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Definition
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Term
| What are 2 advantages of using an inner class? |
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Definition
It can reference data and methods defined in the outer class.
It can make programs more simple. |
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Term
| An inner class is a ________ of another class. |
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Definition
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Term
| An inner class is compiled into a class named. |
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Definition
OuterClassName$InnerClassName.class
example: OuterClass$InnerClass.class |
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Term
| Can an inner class can be defined as static. True or false? |
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Definition
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Term
| How do you access a static inner class? |
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Definition
| Through the outside class. |
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Term
| Can a static class access non-static members of the outer class? |
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Definition
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Term
| Inner class listeners cant be shortened using anonymous inner classes? True or false |
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Definition
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Term
| What is an anonymous inner class? |
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Definition
| an inner class without a name. |
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Term
| What does an anonymous inner class do? |
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Definition
| It combines declaring an inner class and creating an instance of a class in one step. |
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Term
| how do you register a listener object? |
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Definition
you invoke the source objects's addXListener's method.
example: button.AddActionListener(this). |
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Term
| How do you implement a listener interface? |
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Definition
| you add implements XListener and implement all the handlers in the listener's object. |
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Term
| Can a source have multiple listeners? |
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Definition
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Term
| Can a listener listen on multiple sources? |
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Definition
|
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Term
| Can a source be a listener for itself? |
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Definition
|
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Term
| Can an inner class be used in a class other than the class in which it nests? |
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Definition
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Term
| When does the 'mouse entered' event happen? |
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Definition
| when the mouse pointer is moved onto a component. |
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