public abstract boolean drawImage(Image img,
int dx1,
int dy1,
int dx2,
int dy2,
int sx1,
int sy1,
int sx2,
int sy2,
ImageObserver observer) 这个函数里各个参数具体代表了什么啊?还有CANVAS能否为透明?
int dx1,
int dy1,
int dx2,
int dy2,
int sx1,
int sy1,
int sx2,
int sy2,
ImageObserver observer) 这个函数里各个参数具体代表了什么啊?还有CANVAS能否为透明?
img - the specified image to be drawn
dx1 - the x coordinate of the first corner of the destination rectangle.
dy1 - the y coordinate of the first corner of the destination rectangle.
dx2 - the x coordinate of the second corner of the destination rectangle.
dy2 - the y coordinate of the second corner of the destination rectangle.
sx1 - the x coordinate of the first corner of the source rectangle.
sy1 - the y coordinate of the first corner of the source rectangle.
sx2 - the x coordinate of the second corner of the source rectangle.
sy2 - the y coordinate of the second corner of the source rectangle.
observer - object to be notified as more of the image is scaled and converted.
Returns:
true if the current output representation is complete; false otherwise.dx,dy是目的地址,就是要画在画布的范围
sx,sy就是源文件的范围了,复制image的那个范围的图像到画布上咯
observer 是一个component~~JFrame, JPanel之类啦
例子