用Java提取光标图像

could you help me use that function you mentioned?

下面是使用JNA库绘制内置Windows游标的一些代码.如果您可以使用JNA,则可以避免使用C编译器.

我可能会拨打太多原生电话,但是对于一次性图标生成而言,成本并不高.

hand cursor drawn in Java http://f.imagehost.org/0709/hand.png

将光标显示为Java图像的代码：

public class LoadCursor {

  public static void draw(BufferedImage image,int cursor,int diFlags) {
    int width = image.getWidth();
    int height = image.getHeight();

    User32 user32 = User32.INSTANCE;
    Gdi32 gdi32 = Gdi32.INSTANCE;

    Pointer hIcon = user32
        .LoadCursorW(Pointer.NULL,cursor);
    Pointer hdc = gdi32.CreateCompatibleDC(Pointer.NULL);
    Pointer bitmap = gdi32.CreateCompatibleBitmap(hdc,width,height);

    gdi32.SelectObject(hdc,bitmap);
    user32.DrawIconEx(hdc,hIcon,height,Pointer.NULL,diFlags);

    for (int x = 0; x < width; x++) {
      for (int y = 0; y < width; y++) {
        int rgb = gdi32.GetPixel(hdc,x,y);
        image.setRGB(x,y,rgb);
      }
    }

    gdi32.DeleteObject(bitmap);
    gdi32.DeleteDC(hdc);
  }

  public static void main(String[] args) {
    final int width = 128;
    final int height = 128;

    BufferedImage image = new BufferedImage(width,BufferedImage.TYPE_INT_ARGB);
    draw(image,User32.IDC_HAND,User32.DI_NORMAL);
    BufferedImage mask = new BufferedImage(width,BufferedImage.TYPE_INT_RGB);
    draw(mask,User32.DI_MASK);
    applyMask(image,mask);

    JLabel icon = new JLabel();
    icon.setIcon(new ImageIcon(image));

    JFrame frame = new JFrame();
    frame.setDefaultCloSEOperation(JFrame.EXIT_ON_CLOSE);
    frame.setContentPane(icon);
    frame.pack();
    frame.setVisible(true);
  }

  private static void applyMask(BufferedImage image,BufferedImage mask) {
    int width = image.getWidth();
    int height = image.getHeight();
    for (int x = 0; x < width; x++) {
      for (int y = 0; y < height; y++) {
        int masked = mask.getRGB(x,y);
        if ((masked & 0x00FFFFFF) == 0) {
          int rgb = image.getRGB(x,y);
          rgb = 0xFF000000 | rgb;
          image.setRGB(x,rgb);
        }
      }
    }
  }

}

User32.dll接口：

public interface User32 extends Library {

  public static User32 INSTANCE = (User32) Native
      .loadLibrary("User32",User32.class);

  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_ARROW = 32512;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_IBEAM = 32513;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_WAIT = 32514;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_CROSS = 32515;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_UPARROW = 32516;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZENWSE = 32642;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZENESW = 32643;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZEWE = 32644;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZENS = 32645;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZEALL = 32646;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_NO = 32648;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_HAND = 32649;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_APPSTARTING = 32650;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_HELP = 32651;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_ICON = 32641;
  /** @see #LoadCursorW(Pointer,int) */
  public static final int IDC_SIZE = 32640;

  /** @see #DrawIconEx(Pointer,int,Pointer,int) */
  public static final int DI_COMPAT = 4;
  /** @see #DrawIconEx(Pointer,int) */
  public static final int DI_DEFAULTSIZE = 8;
  /** @see #DrawIconEx(Pointer,int) */
  public static final int DI_IMAGE = 2;
  /** @see #DrawIconEx(Pointer,int) */
  public static final int DI_MASK = 1;
  /** @see #DrawIconEx(Pointer,int) */
  public static final int DI_NORMAL = 3;
  /** @see #DrawIconEx(Pointer,int) */
  public static final int DI_APPBANDING = 1;

  /** http://msdn.microsoft.com/en-us/library/ms648391(VS.85).aspx */
  public Pointer LoadCursorW(Pointer hInstance,int lpCursorName);

  /** http://msdn.microsoft.com/en-us/library/ms648065(VS.85).aspx */
  public boolean DrawIconEx(Pointer hdc,int xLeft,int yTop,Pointer hIcon,int cxWidth,int cyWidth,int istepIfAniCur,Pointer hbrFlickerFreeDraw,int diFlags);

}

Gdi32.dll接口：

public interface Gdi32 extends Library {

  public static Gdi32 INSTANCE = (Gdi32) Native
      .loadLibrary("Gdi32",Gdi32.class);

  /** http://msdn.microsoft.com/en-us/library/dd183489(VS.85).aspx */
  public Pointer CreateCompatibleDC(Pointer hdc);

  /** http://msdn.microsoft.com/en-us/library/dd183488(VS.85).aspx */
  public Pointer CreateCompatibleBitmap(Pointer hdc,int nWidth,int nHeight);

  /** http://msdn.microsoft.com/en-us/library/dd162957(VS.85).aspx */
  public Pointer SelectObject(Pointer hdc,Pointer hgdiobj);

  /** http://msdn.microsoft.com/en-us/library/dd145078(VS.85).aspx */
  public int SetPixel(Pointer hdc,int X,int Y,int crColor);

  /** http://msdn.microsoft.com/en-us/library/dd144909(VS.85).aspx */
  public int GetPixel(Pointer hdc,int nXPos,int nYPos);

  /** http://msdn.microsoft.com/en-us/library/dd183539(VS.85).aspx */
  public boolean DeleteObject(Pointer hObject);

  /** http://msdn.microsoft.com/en-us/library/dd183533(VS.85).aspx */
  public boolean DeleteDC(Pointer hdc);

}