Color Selector
Volume Number: | | 9
|
Issue Number: | | 2
|
Column Tag: | | TCL Workshop
|
Related Info: Palette Manager Window Manager Color Manager
Color Quickdraw
A Floating Color Selection
Window for TCL
Creating a floating pallette in TCL without using the Palette Manager
By Paul M. Hyman, Hughes Aircraft Co., Fullerton, CA
Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.
About the author
Paul Hyman is a Systems Engineer with Hughes Aircraft Company. He has developed software on a variety of different systems including Macintosh, Unix/X Windows, and several Hughes-built computers no one has ever heard of.
The Think Class Library provides a useful object oriented application framework for users of Think C. It provides much of the standard Macintosh application functionality, including scrolling windows, menus, and standard AppleEvent handling if youre using System 7, as well as some not-so-standard functionality such as tear-off menus and floating windows.
This article describes some new classes which implement a floating color selection window, which seems to be the way most color drawing and painting programs allow users to select colors these days. This window might sometimes be referred to as a color palette, but I will call it a color selection window to avoid confusion with the palette manager. These classes were developed using Think C 5.0.2 with Think Class Library version 1.1.2.
The color selection window does the following. It shows the available colors in the palette assigned to the active document (up to 256), and highlights the current selection. The size of 256 was chosen since it is appropriate for 8 bit color displays and is used in many programs. You could modify it to be some other size if you want. The window allows the user to select a new color by clicking on it and allows the application to change the currently selected color by sending it a message. It can also inform the application of the current color in response to a message and will notify the current document when the user selects a new color. The color selector is designed to be used as a global object; there is only one and it is always present, even though its window may be hidden if the user clicks in its close box.
The sample program which is shown illustrates how to use this color selection window. It also shows how to maintain a list of objects which the user has created. Basically, it allows the user to create colored boxes (rectangles) in a window and recognizes when one of the boxes has been selected by being clicked on. Boxes are created with the currently selected color. When an existing box is clicked on, its color is selected in the floating window.
As you will unoubtedly notice, I didnt follow the TCL convention of putting C in front of all class names. This distinguishes the new classes from the classes provided with the TCL.
How to Use the Color Selector
If youre starting a new program, you might want to use the color selector sample program as a starting point. Copy the source files from the Starter application (which comes with Think C) into your project folder. These are needed since they serve as superclasses for some of the sample applications classes. If you have the MacTutor disk, you will have the project and resource files and will be ready to go. If not, copy the project and resource files from the Starter application and add in the classes from the color selector sample application.
In order to make use of the color selector window in an existing program, do the following:
1. Put the colordirector, colorselector, and selectorwindow classes into your project.
2. In your document class DoCommand method, add a case for cmdColorSelect, and #include colorselector.h (this is where cmdColorSelect is defined). This will enable your document to receive a notice when the user selects a new color in the color selection window. See the code in the mydoc class for how to handle this message.
3. Copy the code from the Activate method of docwindow into your window class code. This Activate method sends a notification to the color selector window informing it that a new window has been activated and that its palette should be displayed.
4. Override CApplications MakeDesktop method in your application class to create a floating window desktop. See the MakeDesktop method in the myapp class to see how to do this.
5. Copy the code from myapp's Imyapp method into your applications initialization method. This code creates the color selector objects.
You will need to add a few resources to your resource file. You will need to add the windoid WDEF which is supplied with the TCL. You will also need a pltt resource with the same ID as your document window (500 in the case of the sample program described below) unless you build your palette in the code. (The use of palettes is explained more in the next section.) In addition, the sample program has a menu item, Show Color Selector #1025 (the 1025 is the TCL command number), and ALRT 130 for the About box.
The sample program.
The sample program presented with this article allows the user to select a color from the selection window and then create a box of that color in the document window by clicking in some empty spot and dragging down and to the right. Clicking on an existing box causes its color to be selected in the selection window. The program maintains a list of boxes so that they can be drawn when the window is scrolled and so that it can detect when a mouse click occurred in an existing box.
To use the color selection window, each document window must have a color palette associated with it. The easiest way to create a palette is to use Resedit and create a pltt resource with the same id as the id of the WIND resource for the window. Since this program uses a WIND resource of ID 500 to build its document windows, putting in a pltt resource of ID 500 automatically associates the palette with the window. Just for illustrative purposes, the program shows how to create a palette in the code. The first document window (the one that appears when the program starts up) uses the palette from the pltt resource. The second window, which is created when New is selected from the File menu, has a palette of shades of red, while the third window, which is created when New is selected the second time, has a palette of shades of green.
When using the TCL, every program must have an application class. For this demo program, I created a class called myapp, which is a subclass of CStarterApp, the application class that comes with the Starter demo program. If the application has documents, it must also have a document class, as well as a pane class in which to do its drawing. Just as with the application class, I created a document class, mydoc, which is a subclass of CStarterDoc, and a pane class, mypane, which is a subclass of CStarterPane. I could have just modified the classes in the Starter demo rather than creating subclasses, but this would have made it difficult to explain the code which is necessary to use the color selector. By creating subclasses, the new code is isolated in the new classes. I also created a new subclass of CWindow, which I called docwindow, since I needed to modify the window behavior slightly.
In addition to the application, document, and pane classes, there is a class called genericbox, which manages a box on the screen, and boxlist, which keeps a list of all the boxes belonging to a document. The class genericbox is so named because if this program were to be expanded into a drawing program, genericbox would probably be used as an abstract class to give general behavior to boxes on the screen and would be overridden to create specific shapes.
In the following paragraphs, the methods in these new classes and what they do to support the color selection window are briefly described. For more details, refer to the comments in the code.
The application class, myapp:
Imyapp - This is the initialization method. It creates the colordirector object and sends it an initialize message.
DoCommand - This method processes menu selections. In the case of the Show Color Selector menu item, this method sends a Show message to the color selectors window. (The window will be hidden if the user clicked in its close box and this is how it gets made visible again.)
UpdateMenus - This method is responsible for enabling appropriate menu items before a menu is displayed. It simply enables the Show Color Selector menu item. It could be made smarter and only enable it if the window is hidden.
CreateDocument - This is basically the same as the CreateDocument method in the CStarterApp class. The only difference is that it creates a mydoc document instead of a CStarterDoc document.
MakeDesktop - This method creates a floating window desktop instead of the normal kind.
The document class, mydoc:
Imydoc - This is the initialization method. It creates a boxlist object for this document.
BuildWindow - This code is mostly copied from the CStarterDoc code. The main differences are that it creates a docwindow instead of a CWindow and puts a mypane pane in it, and it creates individual color palettes for the second and third document windows.
selectabox - Determines whether the user clicked in an existing box by calling the boxlist objects hitbox method with the mouse location. If the user did click in a box, the box is sent a doselectstuff message.
DoNewBox - Creates a new box, using the currently selected color. This is called after the user has clicked and dragged the mouse to create a box.
DoCommand - Processes the command which is sent when the user changes the selected color in the color selection window. The sample program doesnt do anything here, but it would be the place to implement changing the color of selected boxes.
The pane class, mypane:
Imypane - This is the initialization method. It merely calls the CStarterPane initialization method.
Perform_draw - This method is passed a genericbox object as a parameter and calls its draw method. It is used in conjunction with the DoForEach method of the CList object to call each box to draw itself.
Draw - This method is called when all or part of the pane is to be drawn. A rectangle is passed as an argument which defines the area to be redrawn. This method ignores the rectangle and redraws everything. It makes use of the DoForEach function provided by the TCLs CList class, of which boxlist is a subclass. It calls the DoForEach method of the boxlist belonging to the current document and passes it the Perform_draw function as the function to be executed for each box.
DoClick - This method checks whether the user clicked in an existing box. If not, it tracks the mouse as the user drags it and then calls the documents DoNewBox method to create a new box.
ChangeSize - I copied some code from the ArtClass demo application in here to make the pane scroll correctly. The Starter application does not scroll properly.
The genericbox class, which manages a box on the screen:
Igenericbox - The initialization method. Saves the boxs bounding rectangle and its color.
draw - Draws the box by calling PaintRect.
testhit - Determines whether a point (presumably the mouse location) is inside the box.
doselectstuff - Handles the actions to be taken when the user selects (clicks on) the box. It erases and redraws the box to make it flash, and sends a changecolor message to the color selector so that the boxs color will be selected in the color selector window.
The boxlist class, which manages a list of boxes:
hitbox - This is the only method. Boxlist is a subclass of CList, which is used for managing an ordered list of objects. The additional functionality provided by boxlist is in this method, which calls each objects testhit method to see whether or not the mouse coordinates are inside its box. If one of the boxes returns true, that object is passed back as the function result.
How the Color Selector Works
The Think Class Library provides a class called CGridSelector which allows for the selection of an item in a grid of items. This class serves as the basis for the colorselector class which displays the selection of colors in a 16x16 grid.
There are actually three classes necessary to implement the color selection window: colorselector, selectorwindow, and colordirector. The colorselector class is a subclass of CPane, since CGridSelector (its parent class) is a subclass of CPane. In TCL all drawing is done within Panes. The pane must be placed into a window, and in this case a new class, selectorwindow, which is a subclass of CWindow, is used to hold the colorselector pane. The only difference between selectorwindow and CWindow is that when the close box is clicked in a normal (CWindow) window, the window is closed and the object is deleted. I wanted the object to stay around, so selectorwindow overrides the Close method and simply hides the window. The other class, colordirector, is a subclass of CDirector. In TCL, each window must have a director associated with it. The most common kind of director is CDocument, which manages a normal document window. In the case of the color selector window, a special director, colordirector, is required. The colordirector class has an initialization method which places the window on the screen having the greatest pixel depth, and creates a colorselector Pane to put in the window. It also has a DoCommand method which processes color change commands which the color selector sends.
The following paragraphs describe the methods in these classes. For more details, refer to the comments in the code.
colorselector:
DrawItem - This method draws a single color rectangle in the color selection window. It uses the item number as an index and calls the palette manager to get the appropriate entry color.
HiliteItem - Highlights the item so the user can see which color is selected. The default hiliting method used by GridSelector is to invert the item. This doesnt look good with colors, so this method (which overrides HiliteItem in CGridSelector) draws a rectangle around the item.
currentcolor - Returns the currently selected color and its palette entry number.
windowactivated - This method is called by mydocs Activate method whenever a document window is activated. It copies the document windows palette and associates it with the color selector window. The palette must be associated with the color selector window because as far as the palette manager is concerned, the color selector window is the top window and its palette takes precedence over all other windows.
changecolor - Informs the color selector that the selected color should be changed. This method should be called when the program wishes to change the selected color, such as when the user has selected something and its color should be shown as selected.
colordirector:
Icolordirector - This is the initialization method. It creates the color selector window and puts it on the screen with the greatest pixel depth.
DoCommand - This method forwards the command (which will be a notification of a color selection change) on to the top document. (The colorselector class, by virtue of its inheritance of CGridSelectors behavior, sends a command to its supervisor (the colordirector) whenever the user makes a selection.)
Suspend - Hides the floating window when the application is suspended.
Resume - Shows the floating window when the application is resumed.
Conclusion
By using a class library such as TCL, programmers can take advantage of a framework which provides not only the standard functionality found in most Macintosh applications, but additional functionality such as floating windows. The classes described here extend the TCLs functionality in the form of a floating color selection window, a user interface feature found in many current applications.
Listing: boxlist.h
#pragma once
#include <CList.h>
#include genericbox.h
class boxlist : public CList
{
public:
virtual genericbox *hitbox(Point mouseloc);
};
Listing: boxlist.c
#include boxlist.h
/*********************************************************
boxlist is a subclass of CList. It is used for
keeping a list of boxes which the user has drawn.
It provides one additional method not found in CList,
which is a method to test each box in the list to see
if a mouse click ocurred in it.
**********************************************************/
/*********************************************************
hitbox
Test each box in the list by calling the boxs testhit
method. When a boxs testhit method returns a value of
true, returns this box as the function result.
*********************************************************/
genericbox *boxlist::hitbox(Point mouseloc)
{
short i;
for (i = 0; i < numItems; i++)
{
if (((genericbox *) (*items)[i])->testhit(mouseloc))
{
// Mouseloc is in this box
return (genericbox *)((*items)[i]);
}
}
return 0L;
}
Listing: colordirector.h
#pragma once
#include <CDirector.h>
#include <CApplication.h>
/* Class Declaration */
class colordirector : public CDirector
{
public:
/** Instance Variables **/
/** Instance Methods **/
void Icolordirector(CApplication *aSupervisor);
void DoCommand(long theCommand);
void Suspend(void);
void Resume(void);
};
Listing: colordirector.c
#include colordirector.h
#include colorselector.h
#include <CDesktop.h>
#include selectorwindow.h
#include Global.h
#include <Palettes.h>
#include <Picker.h>
#include <CFWDesktop.h>
extern CDesktop *gDesktop; /* The visible Desktop */
colorselector *gcolorselector;
/* First in line to get commands */
extern CBureaucrat *gGopher;
/********************************************************
Icolordirector
Initializes the colordirector object.
********************************************************/
void colordirector::Icolordirector(CApplication
*aSupervisor)
{
Rect bounds, deeprect;
GDHandle thedevice;
CDirector::IDirector(aSupervisor);
// Find the screen with the most colors (the deepest device)
// And put the window on it
SetRect ( &bounds, -32767, -32767, 32767, 32767);
thedevice = GetMaxDevice(&bounds);
deeprect = (**thedevice).gdRect;
bounds.left = deeprect.left + 40;
bounds.top = deeprect.top + 40;
bounds.bottom = 16*BOXSIZE + bounds.top;
bounds.right = 16*BOXSIZE + bounds.left;
// Create the selector window
itsWindow = (CWindow *)new(selectorwindow);
itsWindow->INewWindow(&bounds, TRUE, 3200, TRUE, TRUE,
gDesktop, this);
// Process the click that activates it
itsWindow->SetActClick(TRUE);
// Create the selector pane
gcolorselector = new colorselector;
gcolorselector->Icolorselector(itsWindow, this, 1,
cmdColorSelect, thedevice);
}
/********************************************************
DoCommand {OVERRIDE}
Execute a command
********************************************************/
void colordirector::DoCommand(long theCommand)
{
CBureaucrat *thesupervisor;
if (theCommand < 0)
{
if (HiShort(-theCommand) == cmdColorSelect)
{
// The color selector palette sent us a color change.
// We want to send it to the current document for
// processing. We do this by sending the command to
// the gopher which will send it up to the
// current document.
gGopher->DoCommand(theCommand);
}
}
else
{
switch (theCommand)
{
default:
inherited::DoCommand(theCommand);
break;
}
}
}
/********************************************************
Suspend {OVERRIDE}
Following the Human Interface Guidelines, tear-off menus
are hidden when the application is suspended. (This is
copied from CTearOffMenu.)
********************************************************/
void colordirector::Suspend()
{
if (active) {
itsWindow->HideSuspend();
((CFWDesktop *) gDesktop)->CalcTopFloat();
active = TRUE;
}
}
/********************************************************
Resume {OVERRIDE}
Resume by showing the tear-off window if it was visible
before we were suspended. (This is copied from
CTearOffMenu.)
********************************************************/
void colordirector::Resume()
{
if (active) {
itsWindow->ShowResume();
((CFWDesktop *) gDesktop)->CalcTopFloat();
}
}
Listing: colorselector.h
#pragma once
#include <CGridSelector.h>
#include <Palette.h>
#define BOXSIZE 10
#define cmdColorSelect 25000
class colorselector : public CGridSelector
{
public:
void Icolorselector(CView *anEnclosure,
CBureaucrat *aSupervisor,
short aSelection, short aCommandBase,
GDHandle thedevice);
virtual void DrawItem(short theItem, Rect *theBox);
virtual void HiliteItem(short theItem,
HiliteState state);
void currentcolor(RGBColor *thecolor,
short *theentry);
void windowactivated(WindowPtr thewindow);
void changecolor(short thecolor);
short prevhiliteitem;
PaletteHandle ph;
};
Listing: colorselector.c
#include colorselector.h
void colorselector::Icolorselector(CView *anEnclosure,
CBureaucrat *aSupervisor, short aSelection,
short aCommandBase, GDHandle thedevice)
{
CGridSelector::IGridSelector(anEnclosure, aSupervisor, 0, 0,
sizFIXEDLEFT, sizFIXEDTOP,
aSelection, aCommandBase,
16,16, BOXSIZE, BOXSIZE);
prevhiliteitem = 0; // No previous item hilighted
ph = 0L; // No palette exists
}
/**********************************************************
DrawItem {OVERRIDE}
Draws the appropriate color in the rectangle. Finds the
color from the palette.
*********************************************************/
void colorselector::DrawItem(short theItem, Rect *theBox)
{
RGBColor oldcolor;
GDHandle curdevice;
RGBColor curcolor;
short pixdepth;
Lock(TRUE);
if (ph)
{
// If theItem is withing the number of entries in the
// windows palette, draw the rectangle in the
// appropriate color. Otherwise, draw it as black.
if ((theItem-1) < (**ph).pmEntries)
{
GetEntryColor(ph, theItem-1, &curcolor);
}
else
{
curcolor.red = curcolor.green = curcolor.blue = 0;
}
GetForeColor ( &oldcolor );
RGBForeColor( &curcolor );
PaintRect(theBox);
RGBForeColor( &oldcolor );
}
else
{
// No palette associated with the window. Draw the first
// entry as white and the others as black.
if (theItem == 1)
curcolor.red = curcolor.green = curcolor.blue = 0xFFFF;
// white
else
curcolor.red = curcolor.green = curcolor.blue = 0;
// black
GetForeColor ( &oldcolor );
RGBForeColor( &curcolor );
PaintRect(theBox);
RGBForeColor( &oldcolor );
}
Lock(FALSE);
}
/**********************************************************
HiliteItem {OVERRIDE}
The default hiliting method used by GridSelector is to
invert the item. This doesnt look good with colors, so
we draw a rectangle around the item.
**********************************************************/
void colorselector::HiliteItem(
short theItem, /* Item number to hilite */
HiliteState state)/* State of hiliting desired */
{
Rect theRect;
register Rect *theBox;
long ticks;
if (theItem == 0)
return;
if (prevhiliteitem != 0)
{
// Unhilite the previous item
FindItemBox(prevhiliteitem, &theRect);
DrawItem(prevhiliteitem, &theRect);
InsetRect(&theRect, -1, -1);
FrameRect(&theRect);
}
// Get the items rectangle
FindItemBox(theItem, &theRect);
theBox = &theRect;
// Draw a white rectangle inside of a black rectangle
// around the color
InsetRect(theBox, -1, -1);
ForeColor(whiteColor);
FrameRect(theBox);
ForeColor(blackColor);
InsetRect(theBox, 1, 1);
FrameRect(theBox);
prevhiliteitem = theItem;
}
/*********************************************************
currentcolor
Returns currently selected color.
**********************************************************/
void colorselector::currentcolor(RGBColor *thecolor,
short *theentry)
{
GDHandle curdevice;
Lock(TRUE);
*theentry = selection;
if (ph)
{
if ((selection-1) < (**ph).pmEntries)
{
GetEntryColor(ph, (selection-1), thecolor);
}
else
{
thecolor->red = thecolor->green = thecolor->blue = 0;
}
}
else
{
if (selection == 1)
thecolor->red = thecolor->green =
thecolor->blue = 0xFFFF;
else
thecolor->red = thecolor->green = thecolor->blue = 0;
}
Lock(FALSE);
}
/********************************************************
windowactivated
This function is called by a document window when the
window is activated. It copies the palette associated
with the window and associates it with the floating color
selection window so that the correct colors are
displayed.
*********************************************************/
void colorselector::windowactivated(WindowPtr thewindow)
{
PaletteHandle newph;
Rect tmprect;
GrafPtrsavePort;/* The current port */
GetPort(&savePort); /* Save the original port */
SetPort(macPort);
Lock(TRUE);
// Get palette associated with the activated document window
ph = GetPalette(macPort);
if (ph)
{
DisposePalette(ph); // Get rid of it
ph = 0L;
}
newph = GetPalette(thewindow);
if (newph)
{
ph = newph;
HandToHand ( &ph ); // Make a copy of the palette
// associate the palette with our selection window
SetPalette(macPort, ph, TRUE);
ActivatePalette(macPort);
}
Lock(FALSE);
// Make sure the window gets redrawn
InvalRect(&(macPort->portRect));
SetPort(savePort);/* Restore the original port */
}
void colorselector::changecolor(short thecolor)
{
GrafPtrsavePort;/* The current port */
GetPort(&savePort); /* Save the original port */
Prepare(); /* Set up Windows port */
ChangeSelection(thecolor);
SetPort(savePort);/* Restore the original port */
ForceNextPrepare();
}
Listing: docwindow.h
#pragma once
#include <CWindow.h>
class docwindow : public CWindow
{
public:
virtual void Activate(void);
};
Listing: docwindow.c
#include docwindow.h
#include colorselector.h
extern colorselector *gcolorselector;// The color selector palette (pane)
/*********************************************************
Activate
Notify the color selector object that this document
window has become active.
*********************************************************/
void docwindow::Activate(void)
{
Rect tmprect;
inherited::Activate();
gcolorselector->windowactivated(macPort);
}
Listing: genericbox.h
/********************************************************
genericbox.h
Interface for the genericbox Class
********************************************************/
#pragma once
#include <CObject.h> /* Interface for its superclass */
class genericbox : public CObject
{/* Class Declaration */
public:
/** Instance Variables **/
Rect boxrect; // The boxs rectangle
RGBColor boxcolor;// The boxs color
short colorentry;// The palette entry for
// this boxs color
/** Instance Methods **/
void Igenericbox(Rect *therect, RGBColor *thecolor,
short colorentry);
virtual void draw(void);
Boolean testhit(Point mouseloc);
void doselectstuff(void);
};
Listing: genericbox.c
#include <CObject.h>
#include genericbox.h
#include colorselector.h
// The color selector pane
extern colorselector *gcolorselector;
/********************************************************
Igenericbox
Initialize a generic box. The boxs rectangle, color,
and its color index in the palette are saved. We keep
the palette index as well as the RGB color itself because
when we want to tell the color selection window to
display the color of this box there is no convenient way
to go from an RGB color to a palette index.
********************************************************/
void genericbox::Igenericbox(Rect *therect,
RGBColor *thecolor, short colorentry)
{
boxrect = *therect;
boxcolor = *thecolor;
this->colorentry = colorentry;
}
/********************************************************
draw
Draws a generic box by painting a rectangle in the
boxs color.
********************************************************/
void genericbox::draw(void)
{
Lock(TRUE);
RGBForeColor(&boxcolor);
PaintRect(&boxrect);
Lock(FALSE);
}
/********************************************************
testhit
Returns true if the point is inside the box.
********************************************************/
Boolean genericbox::testhit(Point mouseloc)
{
Boolean result;
Lock(TRUE);
result = PtInRect ( mouseloc, &boxrect );
Lock(FALSE);
return result;
}
/*********************************************************
doselectstuff
This method is invoked when the user has selected this
box by clicking on it. It sends a message to the color
selection window to change the currently selected color
to the color of this box.
********************************************************/
void genericbox::doselectstuff(void)
{
Lock(TRUE);
EraseRect(&boxrect);// Erase the box (& redraw it
// later to make it flash)
// Change selected color to this boxs
gcolorselector->changecolor(colorentry);
RGBForeColor(&boxcolor);
PaintRect(&boxrect);
Lock(FALSE);
}
Listing: selectorwindow.h
#pragma once
#include <CWindow.h>
/* Class Declaration */
class selectorwindow : public CWindow {
public:
virtual void Close(void);
};
Listing: selectorwindow.c
#include selectorwindow.h
/********************************************************
Close
Respond to a click in the close box. We just hide the
window instead of deleting it.
********************************************************/
void selectorwindow::Close()
{
Hide();
}
Listing: mypane.c
#pragma once
/****
* mypane.h
*
*
****/
#include CStarterPane.h
struct mypane : CStarterPane
{
void Imypane(CView *anEnclosure, CBureaucrat *aSupervisor,
short aWidth, short aHeight,
short aHEncl, short aVEncl,
SizingOption aHSizing, SizingOption aVSizing);
void Draw(Rect *area);
void DoClick(Point hitPt, short modifierKeys, long when);
void ChangeSize(register Rect *delta, Boolean redraw);
};
Listing: mypane.c
/****
* mypane.c
*
*
****/
/**
*
* Initialization method. Simply calls the superclasss
* initialization method.
*
**/
#include mypane.h
#include mydoc.h
#include genericbox.h
void Perform_draw(genericbox *thebox);
void mypane::Imypane(CView *anEnclosure,
CBureaucrat *aSupervisor,
short aWidth, short aHeight,
short aHEncl, short aVEncl,
SizingOption aHSizing, SizingOption aVSizing)
{
CStarterPane::IStarterPane(anEnclosure, aSupervisor,
aWidth, aHeight, aHEncl, aVEncl, aHSizing, aVSizing);
}
/***
Perform_draw
Iteration procedure for drawing each box in the box list. It is called
by the DoForEach method of the boxlist object. See the Draw function
here for more information.
***/
static void Perform_draw(genericbox *thebox)
{
thebox->draw();
}
/***
* Draw
*
* Draw the contents of the pane.
***/
void mypane::Draw(Rect *area)
{
// Sends a DoForEach message to the boxlist object belonging
// to the panes supervisor (the document). Object oriented
// purists will undoubtedly gag at referencing an instance
// variable belonging to another class. The pure way to
// do this would be to send a message to the document
// requesting that it call the DoForEach method of its
// boxlist, but that would require another method in
// the document class.
((mydoc *)itsSupervisor)->boxlist->DoForEach(Perform_draw);
}
/***
* DoClick
*
* The mouse went down in the pane.
* If the click was in an existing box, select the box.
* Otherwise, draw a new one.
*
***/
void mypane::DoClick(Point hitPt, short modifierKeys,
long when)
{
/* what happens when the mouse goes down */
Rect tmprect;
Point dragpt,prevdragpt;
Boolean first;
CursHandle crosscursor;
if (!(((mydoc *)itsSupervisor)->selectabox(hitPt)))
{
// Didnt select one.
// Track the mouse, drawing a rubber band rectangle.
first = TRUE;
prevdragpt = hitPt;
PenMode ( patXor );
SetRect ( &tmprect, hitPt.h, hitPt.v, hitPt.h+100,
hitPt.v+100 );
crosscursor = GetCursor ( crossCursor );
SetCursor ( *crosscursor );
while (StillDown())
{
GetMouse(&dragpt);
if (!EqualPt(dragpt,prevdragpt))
{
if (!first)
{
// Erase the previous rectangle
SetRect ( &tmprect, hitPt.h, hitPt.v,
prevdragpt.h, prevdragpt.v );
FrameRect(&tmprect);
}
first = FALSE;
// Draw the new rectangle
SetRect ( &tmprect, hitPt.h, hitPt.v,
dragpt.h, dragpt.v );
FrameRect(&tmprect);
prevdragpt = dragpt;
}
}
if (!first) FrameRect(&tmprect); // Erase the last one
InitCursor();
PenMode(patCopy);
Lock(TRUE);
((mydoc *)itsSupervisor)->DoNewBox(&tmprect);
Lock(FALSE);
}
}
/********************************************************
ChangeSize
Change the size. If necessary, shift drawing so
that it always completely covers the frame. (This code
is copied from the Art Class sample application. It
makes scrolling work correctly.)
********************************************************/
void mypane::ChangeSize(
register Rect *delta, /* Movement for each side */
Booleanredraw) /* Redraw Pane or not? */
{
short hShift;
short vShift;
/* If new size would cause the */
/* frame to extend beyond the */
/* bounds of the diagram, we */
/* have to shift the diagram. */
hShift = Max(frame.right + delta->right - bounds.right, 0);
vShift = Max(frame.bottom + delta->bottom -
bounds.bottom, 0);
inherited::ChangeSize(delta, redraw);
if ( (hShift > 0) || (vShift > 0) ) {
Scroll(-hShift, -vShift, false);
if (redraw) {
Refresh();
}
}
}
Listing: mydoc.h
#pragma once
/****
* mydoc.h
*
*
****/
#include CStarterDoc.h
#include <CApplication.h>
#include <CList.h>
#include boxlist.h
struct mydoc : CStarterDoc {
Rect docsizerect;
short rightbound;
short bottombound;
boxlist*boxlist;
void Imydoc(CApplication *aSupervisor,
Boolean printable);
void BuildWindow(Handle theData);
void DoNewBox(Rect *boxrect);
Booleanselectabox(Point testpoint);
void DoCommand(long theCommand);
};
Listing: mydoc.c
/****
* mydoc.c
*
* Document methods for a typical application.
*
* Copyright © 1990 Symantec Corporation.
* All rights reserved.
*
****/
#include Global.h
#include Commands.h
#include CApplication.h
#include CBartender.h
#include CDataFile.h
#include CDecorator.h
#include CDesktop.h
#include CError.h
#include CPanorama.h
#include CScrollPane.h
#include mydoc.h
#include mypane.h
#include TBUtilities.h
#include <Packages.h>
#include <CPaneBorder.h>
#include genericbox.h
#include colorselector.h
#include docwindow.h
#include <Palettes.h>
#include <Picker.h>
#define WINDStarter500 /* Res ID for WIND template */
extern CApplication *gApplication;/* The application */
extern CDecorator *gDecorator; /* Window dressing object */
/* The enclosure for all windows */
extern CDesktop *gDesktop;
/* The current boss in the chain of command */
extern CBureaucrat*gGopher;
extern OSType gSignature;/* The applications signature */
extern CError *gError; /* The global error handler */
// The color selector palette (pane)
extern colorselector *gcolorselector;
/* The menu handling object */
extern CBartender *gBartender;
/***
* Imydoc
*
* Initialize the document by setting its window size and
* creating a boxlist for it.
***/
void mydoc::Imydoc(CApplication *aSupervisor,
Boolean printable)
{
CStarterDoc::IDocument(aSupervisor, printable);
// Set the window size to be the printed page size
rightbound = pageWidth;
bottombound = pageHeight;
SetRect ( &docsizerect, 100, 100, rightbound+15,
bottombound+15 );
// Create the list to hold all the boxes.
boxlist = new boxlist;
boxlist->IList();
}
/***
* BuildWindow
* Most of this is lifted from the CStarterDoc code, except
* for the Pane type and the code to create the palettes.
*
***/
void mydoc::BuildWindow (Handle theData)
{
CScrollPane*theScrollPane;
mypane *theMainPane;
GrafPtr theport;
PaletteHandle bp;
RGBColor rgbc;
long i;
short wcount;
itsWindow = new docwindow;
itsWindow->IWindow(WINDStarter, FALSE, gDesktop, this);
wcount = gDecorator->GetWCount();
if (wcount == 1)
{
// Give the second window a palette of red colors
theport = itsWindow->GetMacPort();
bp = NewPalette(250, 0L, pmTolerant, 0);
rgbc.blue = 0;
rgbc.green = 0;
for (i=0; i<250; i++)
{
rgbc.red = (i*65535)/250;
SetEntryColor(bp, i, &rgbc);
}
SetPalette(theport, bp, TRUE);
}
else if (wcount == 2)
{
// Give the third window a palette of green colors
theport = itsWindow->GetMacPort();
bp = NewPalette(200, 0L, pmTolerant, 0);
rgbc.blue = 0;
rgbc.red = 0;
for (i=0; i<200; i++)
{
rgbc.green = (i*65535)/200;
SetEntryColor(bp, i, &rgbc);
}
SetPalette(theport, bp, TRUE);
}
itsWindow->SetSizeRect(&docsizerect);
theScrollPane = new(CScrollPane);
theScrollPane->IScrollPane(itsWindow, this, 10, 10, 0, 0,
sizELASTIC, sizELASTIC,
TRUE, TRUE, TRUE);
theScrollPane->FitToEnclFrame(TRUE, TRUE);
theMainPane = new(mypane);
theMainPane->Imypane(theScrollPane, this, rightbound,
bottombound, 0, 0, sizELASTIC, sizELASTIC);
itsMainPane = theMainPane;
itsGopher = theMainPane;
theMainPane->FitToEnclosure(TRUE, TRUE);
theScrollPane->InstallPanorama(theMainPane);
gDecorator->PlaceNewWindow(itsWindow);
theMainPane->SetWantsClicks (true);
}
/***
* selectabox
*
* Returns true if a box was selected (clicked in) and
* false otherwise. If a box was selected, its
* doselectstuff method is called.
***/
Boolean mydoc::selectabox(Point testpoint)
{
genericbox *gbox;
gbox = 0;
Lock(TRUE);
// Ask the boxlist to check each box. It will return the box
// object which was selected or null if none was selected.
if ((gbox = boxlist->hitbox(testpoint)) != 0L)
{
gbox->doselectstuff();
}
Lock(FALSE);
return (gbox != 0);
}
/***
* DoNewBox
*
* Create a new box.
***/
void mydoc::DoNewBox(Rect *boxrect)
{
genericbox *gbox;
RGBColor thecolor;
short colorentry;
Lock(TRUE);
// Get the currently selected color from
// the color selection palette
gcolorselector->currentcolor(&thecolor, &colorentry);
gbox = new genericbox;
gbox->Igenericbox(boxrect, &thecolor, colorentry);
gbox->draw();
boxlist->Append((CObject *)gbox);
Lock(FALSE);
}
void mydoc::DoCommand(long theCommand)
{
if (HiShort(-theCommand) == cmdColorSelect)
{
// Color selection change. The low word has
// the current color number. The currentcolor method of
// gColorselector could also be called here
// to get the current entry number and RGB value.
// This would be the place where we might check for
// selected boxes and change their color. Right now,
// we dont do anything.
FlashMenuBar(0); // Just to see something happen
FlashMenuBar(0);
}
else
{
inherited::DoCommand(theCommand);
}
}
Listing: myapp.h
#pragma once
/*****
* myapp.h
*
*****/
#include CStarterApp.h
#include <CWindow.h>
#include <CDirector.h>
#include colordirector.h
class myapp : public CStarterApp
{
public:
void Imyapp(void);
void UpdateMenus(void);
void DoCommand(long theCommand);
void CreateDocument(void);
void MakeDesktop(void);
protected:
colordirector *thecolordirector;
};
Listing: myapp.c
/*****
* myapp.c
*
* Application class for the sample program to illustrate
* use of the color selector window.
* Note: This application does not check for the existence
* of color quickdraw. Obviously, you should do this in a
* real program before calling color routines, but I didnt
* want to add a lot of extra code.
*****/
#include myapp.h
#include mydoc.h
#include <CFWDesktop.h>
#include <CBartender.h>
#include <Commands.h>
#include colordirector.h
#include colorselector.h
extern OSType gSignature;
extern CDesktop *gDesktop; /* The visible Desktop */
extern CBartender*gBartender; /* Manages all menus */
// The color selector palette (pane)
extern colorselector *gcolorselector;
/***
* Imyapp
*
* Initialize the application. Creates the
* colordirector object.
***/
void myapp::Imyapp(void)
{
CStarterApp::IStarterApp(); // Call inherited initialization
thecolordirector = new colordirector;
thecolordirector->Icolordirector(this);
}
/***
* DoCommand
*
* Processes a menu selection.
***/
void myapp::DoCommand(long theCommand)
{
switch (theCommand)
{
case cmdAbout:
Alert(130, 0L); // Show the about box
break;
case 1025:
// 1025 is the command number assigned
// to the Show Color Selector menu item
// Tell the window to show itself
gcolorselector->itsEnclosure->Show();
break;
default:
inherited::DoCommand(theCommand);
break;
}
}
/***
*
* UpdateMenus
*
* Enable/Disable appropriate menu items.
*
***/
void myapp::UpdateMenus()
{
/* Enable standard commands */
inherited::UpdateMenus();
/* Enable Show Color Selector */
gBartender->EnableCmd(1025);
}
/***
* CreateDocument
*
* The user chose New from the File menu, so create
* a new document.
***/
void myapp::CreateDocument()
{
mydoc *theDocument = NULL;
TRY
{
theDocument = new(mydoc);
theDocument->Imydoc(this, TRUE);
theDocument->NewFile();
}
CATCH
{
if (theDocument) theDocument->Dispose();
}
ENDTRY;
}
/********************************************************
MakeDesktop
Create the global Desktop object, which is the top level
of the visual hierarchy. Overrrides the standard method
to use a desktop which supports floating windows.
*********************************************************/
void myapp::MakeDesktop()
{
/* Use a floating window Desktop */
gDesktop = new(CFWDesktop);
((CFWDesktop *)gDesktop)->IFWDesktop(this);
}
Listing: main.c
/********************************************************
main.c
********************************************************/
#include myapp.h
void main()
{
myapp *StarterApp;
StarterApp = new myapp;
StarterApp->Imyapp();
StarterApp->Run();
StarterApp->Exit();
}