UIElementUtilities.m

/*
     File: UIElementUtilities.m 
 Abstract: Utility methods to manage AXUIElementRef instances.
  
  Version: 1.4 
  
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 */
 
#import "UIElementUtilities.h"
 
NSString *const UIElementUtilitiesNoDescription = @"No Description";
 
@implementation UIElementUtilities
 
 
#pragma mark -
 
+ (pid_t)processIdentifierOfUIElement:(AXUIElementRef)element {
    pid_t pid = 0;   
    if (AXUIElementGetPid (element, &pid) == kAXErrorSuccess) {
    return pid;
    } else {
    return 0;
    }
}
 
+ (NSArray *)attributeNamesOfUIElement:(AXUIElementRef)element {
    NSArray *attrNames = nil;
    
    AXUIElementCopyAttributeNames(element, (CFArrayRef *)&attrNames);
    
    return [attrNames autorelease];
}
 
+ (NSArray *)actionNamesOfUIElement:(AXUIElementRef)element {
    NSArray *actionNames = nil;
    
    AXUIElementCopyActionNames(element, (CFArrayRef *)&actionNames);
    
    return [actionNames autorelease];
}
 
 
+ (NSString *)descriptionOfAction:(NSString *)actionName ofUIElement:(AXUIElementRef)element {
    NSString *actionDescription = nil;
    
    AXUIElementCopyActionDescription(element, (CFStringRef)actionName, (CFStringRef *)&actionDescription);
    
    return [actionDescription autorelease];
}
 
+ (void)performAction:(NSString *)actionName ofUIElement:(AXUIElementRef)element {
    AXUIElementPerformAction( element, (CFStringRef)actionName);
}
 
// -------------------------------------------------------------------------------
//  valueOfExistingAttribute:attribute:element
//
//  Given a uiElement and its attribute, return the value of an accessibility object's attribute.
// -------------------------------------------------------------------------------
+ (id)valueOfAttribute:(NSString *)attribute ofUIElement:(AXUIElementRef)element
{
    id result = nil;
    NSArray *attributeNames = [UIElementUtilities attributeNamesOfUIElement:element];
    
    if (attributeNames) {
        if ( [attributeNames indexOfObject:(NSString *)attribute] != NSNotFound
                &&
            AXUIElementCopyAttributeValue(element, (CFStringRef)attribute, (CFTypeRef *)&result) == kAXErrorSuccess
        ) {
            [result autorelease];
        }
    }
    return result;
}
 
+ (BOOL)canSetAttribute:(NSString *)attributeName ofUIElement:(AXUIElementRef)element {
    Boolean isSettable = false;
    
    AXUIElementIsAttributeSettable(element, (CFStringRef)attributeName, &isSettable);
        
    return (BOOL)isSettable;
}
 
+ (void)setStringValue:(NSString *)stringValue forAttribute:(NSString *)attributeName ofUIElement:(AXUIElementRef)element;
{
    CFTypeRef   theCurrentValue     = NULL;
        
    // First, found out what type of value it is.
    if ( attributeName
        && AXUIElementCopyAttributeValue( element, (CFStringRef)attributeName, &theCurrentValue ) == kAXErrorSuccess
        && theCurrentValue) {
    
        CFTypeRef   valueRef = NULL;
 
        // Set the value using based on the type
        if (AXValueGetType(theCurrentValue) == kAXValueCGPointType) {       // CGPoint
        float x, y;
            sscanf( [stringValue UTF8String], "x=%g y=%g", &x, &y );
        CGPoint point = CGPointMake(x, y);
            valueRef = AXValueCreate( kAXValueCGPointType, (const void *)&point );
            if (valueRef) {
                AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, valueRef );
                CFRelease( valueRef );
            }
        }
        else if (AXValueGetType(theCurrentValue) == kAXValueCGSizeType) {   // CGSize
        float w, h;
            sscanf( [stringValue UTF8String], "w=%g h=%g", &w, &h );
            CGSize size = CGSizeMake(w, h);
            valueRef = AXValueCreate( kAXValueCGSizeType, (const void *)&size );
            if (valueRef) {
                AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, valueRef );
                CFRelease( valueRef );
            }
        }
        else if (AXValueGetType(theCurrentValue) == kAXValueCGRectType) {   // CGRect
        float x, y, w, h;
            sscanf( [stringValue UTF8String], "x=%g y=%g w=%g h=%g", &x, &y, &w, &h );
        CGRect rect = CGRectMake(x, y, w, h);
            valueRef = AXValueCreate( kAXValueCGRectType, (const void *)&rect );
            if (valueRef) {
                AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, valueRef );
                CFRelease( valueRef );
            }
        }
        else if (AXValueGetType(theCurrentValue) == kAXValueCFRangeType) {  // CFRange
            CFRange range;
            sscanf( [stringValue UTF8String], "pos=%ld len=%ld", &(range.location), &(range.length) );
            valueRef = AXValueCreate( kAXValueCFRangeType, (const void *)&range );
            if (valueRef) {
                AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, valueRef );
                CFRelease( valueRef );
            }
        }
        else if ([(id)theCurrentValue isKindOfClass:[NSString class]]) {    // NSString
            AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, stringValue );
        }
        else if ([(id)theCurrentValue isKindOfClass:[NSValue class]]) {     // NSValue
            AXUIElementSetAttributeValue( element, (CFStringRef)attributeName, [NSNumber numberWithFloat:[stringValue floatValue]] );
        }
    }
}
 
 
+ (AXUIElementRef)parentOfUIElement:(AXUIElementRef)element {
        return (AXUIElementRef)[UIElementUtilities valueOfAttribute:NSAccessibilityParentAttribute ofUIElement:element];
}
 
+ (NSString *)roleOfUIElement:(AXUIElementRef)element {
        return (NSString *)[UIElementUtilities valueOfAttribute:NSAccessibilityRoleAttribute ofUIElement:element];
}
 
+ (NSString *)titleOfUIElement:(AXUIElementRef)element {
        return (NSString *)[UIElementUtilities valueOfAttribute:NSAccessibilityTitleAttribute ofUIElement:element];
}
 
+ (BOOL)isApplicationUIElement:(AXUIElementRef)element {
    return [[UIElementUtilities roleOfUIElement:element] isEqualToString:NSAccessibilityApplicationRole];
}
 
 
 
#pragma mark -
 
// Flip coordinates
 
+ (CGPoint)carbonScreenPointFromCocoaScreenPoint:(NSPoint)cocoaPoint {
    NSScreen *foundScreen = nil;
    CGPoint thePoint;
    
    for (NSScreen *screen in [NSScreen screens]) {
    if (NSPointInRect(cocoaPoint, [screen frame])) {
        foundScreen = screen;
    }
    }
 
    if (foundScreen) {
    CGFloat screenHeight = [foundScreen frame].size.height;
    
    thePoint = CGPointMake(cocoaPoint.x, screenHeight - cocoaPoint.y - 1);
    } else {
    thePoint = CGPointMake(0.0, 0.0);
    }
 
    return thePoint;
}
 
 
// -------------------------------------------------------------------------------
//  FlippedScreenBounds:bounds
// -------------------------------------------------------------------------------
+ (NSRect) flippedScreenBounds:(NSRect) bounds
{
    float screenHeight = NSMaxY([[[NSScreen screens] objectAtIndex:0] frame]);
    bounds.origin.y = screenHeight - NSMaxY(bounds);
    return bounds;
}
 
 
+ (NSRect)frameOfUIElement:(AXUIElementRef)element {
 
    NSRect bounds = NSZeroRect;
    
    id elementPosition = [UIElementUtilities valueOfAttribute:NSAccessibilityPositionAttribute ofUIElement:element];
    id elementSize = [UIElementUtilities valueOfAttribute:NSAccessibilitySizeAttribute ofUIElement:element];
    
    if (elementPosition && elementSize) {
        NSRect topLeftWindowRect;
        AXValueGetValue((AXValueRef)elementPosition, kAXValueCGPointType, &topLeftWindowRect.origin);
        AXValueGetValue((AXValueRef)elementSize, kAXValueCGSizeType, &topLeftWindowRect.size);
        bounds = [self flippedScreenBounds:topLeftWindowRect];
    }
    return bounds;
}
 
#pragma mark -
#pragma mark String Descriptions
 
 
// -------------------------------------------------------------------------------
//  stringDescriptionOfAXValue:valueRef:beVerbose
//
//  Returns a descriptive string according to the values' structure type.
// -------------------------------------------------------------------------------
+ (NSString *)stringDescriptionOfAXValue:(CFTypeRef)valueRef beingVerbose:(BOOL)beVerbose
{
    NSString *result = @"AXValue???";
    
    switch (AXValueGetType(valueRef)) {
        case kAXValueCGPointType: {
            CGPoint point;
            if (AXValueGetValue(valueRef, kAXValueCGPointType, &point)) {
                if (beVerbose)
                    result = [NSString stringWithFormat:@"<AXPointValue x=%g y=%g>", point.x, point.y];
                else
                    result = [NSString stringWithFormat:@"x=%g y=%g", point.x, point.y];
            }
            break;
        }
        case kAXValueCGSizeType: {
            CGSize size;
            if (AXValueGetValue(valueRef, kAXValueCGSizeType, &size)) {
                if (beVerbose)
                    result = [NSString stringWithFormat:@"<AXSizeValue w=%g h=%g>", size.width, size.height];
                else
                    result = [NSString stringWithFormat:@"w=%g h=%g", size.width, size.height];
            }
            break;
        }
        case kAXValueCGRectType: {
            CGRect rect;
            if (AXValueGetValue(valueRef, kAXValueCGRectType, &rect)) {
                if (beVerbose)
                    result = [NSString stringWithFormat:@"<AXRectValue  x=%g y=%g w=%g h=%g>", rect.origin.x, rect.origin.y, rect.size.width, rect.size.height];
                else
                    result = [NSString stringWithFormat:@"x=%g y=%g w=%g h=%g", rect.origin.x, rect.origin.y, rect.size.width, rect.size.height];
            }
            break;
        }
        case kAXValueCFRangeType: {
            CFRange range;
            if (AXValueGetValue(valueRef, kAXValueCFRangeType, &range)) {
                if (beVerbose)
                    result = [NSString stringWithFormat:@"<AXRangeValue pos=%ld len=%ld>", range.location, range.length];
                else
                    result = [NSString stringWithFormat:@"pos=%ld len=%ld", range.location, range.length];
            }
            break;
        }
        default:
            break;
    }
    return result;
}
 
 
 
// -------------------------------------------------------------------------------
//  descriptionOfValue:theValue:beVerbose
//
//  Called from "descriptionForUIElement", return a descripting string (role and title)
//  of the given value (AXUIElementRef).
// -------------------------------------------------------------------------------
+ (NSString *)descriptionOfValue:(CFTypeRef)theValue beingVerbose:(BOOL)beVerbose
{
    NSString *  theValueDescString  = NULL;
 
    if (theValue) {
    
        if (AXValueGetType(theValue) != kAXValueIllegalType) {
            theValueDescString = [self stringDescriptionOfAXValue:theValue beingVerbose:beVerbose];
        }
        else if (CFGetTypeID(theValue) == CFArrayGetTypeID()) {
            theValueDescString = [NSString stringWithFormat:@"<array of size %d>", [(NSArray *)theValue count]];
        }
        else if (CFGetTypeID(theValue) == AXUIElementGetTypeID()) {
            
            NSString *  uiElementRole   = NULL;
        
            if (AXUIElementCopyAttributeValue( (AXUIElementRef)theValue, kAXRoleAttribute, (CFTypeRef *)&uiElementRole ) == kAXErrorSuccess) {
                NSString *  uiElementTitle  = NULL;
                
                uiElementTitle = [self valueOfAttribute:NSAccessibilityTitleAttribute ofUIElement:(AXUIElementRef)theValue];
                
                #if 0
                // hack to work around cocoa app objects not having titles yet
                if (uiElementTitle == nil && [uiElementRole isEqualToString:(NSString *)kAXApplicationRole]) {
                    pid_t               theAppPID = 0;
                    ProcessSerialNumber theAppPSN = {0,0};
                    NSString *          theAppName = NULL;
                    
                    if (AXUIElementGetPid( (AXUIElementRef)theValue, &theAppPID ) == kAXErrorSuccess
                        && GetProcessForPID( theAppPID, &theAppPSN ) == noErr
                        && CopyProcessName( &theAppPSN, (CFStringRef *)&theAppName ) == noErr ) {
                        uiElementTitle = theAppName;
                    }
                }
                #endif
 
                if (uiElementTitle != nil) {
                    theValueDescString = [NSString stringWithFormat:@"<%@: “%@”>", uiElementRole, uiElementTitle];
                }
                else {
                    theValueDescString = [NSString stringWithFormat:@"<%@>", uiElementRole];
                }
                [uiElementRole release];
            }
            else {
                theValueDescString = [(id)theValue description];
            }
        }
        else {
            theValueDescString = [(id)theValue description];
        }
    }
    
    return theValueDescString;
}
 
// -------------------------------------------------------------------------------
//  lineageOfUIElement:element
//
//  Return the lineage array or inheritance of a given uiElement.
// -------------------------------------------------------------------------------
+ (NSArray *)lineageOfUIElement:(AXUIElementRef)element
{
    NSArray *lineage = [NSArray array];
    NSString *elementDescr = [self descriptionOfValue:element beingVerbose:NO];
    AXUIElementRef parent = (AXUIElementRef)[self valueOfAttribute:NSAccessibilityParentAttribute ofUIElement:element];
 
    if (parent != NULL) {
        lineage = [self lineageOfUIElement:parent];
    }
    return [lineage arrayByAddingObject:elementDescr];
}
 
// -------------------------------------------------------------------------------
//  lineageDescriptionOfUIElement:element
//
//  Return the descriptive string of a uiElement's lineage.
// -------------------------------------------------------------------------------
+ (NSString *)lineageDescriptionOfUIElement:(AXUIElementRef)element
{
    NSMutableString *result = [NSMutableString string];
    NSMutableString *indent = [NSMutableString string];
    NSArray *lineage = [self lineageOfUIElement:element];
    NSString *ancestor;
    NSEnumerator *e = [lineage objectEnumerator];
    while (ancestor = [e nextObject]) {
        [result appendFormat:@"%@%@\n", indent, ancestor];
        [indent appendString:@" "];
    }
    return result;
}
 
// -------------------------------------------------------------------------------
//  stringDescriptionOfUIElement:inElement
//
//  Return a descriptive string of attributes and actions of a given uiElement.
// -------------------------------------------------------------------------------
+ (NSString *)stringDescriptionOfUIElement:(AXUIElementRef)element
{
    NSMutableString *   theDescriptionStr = [[NSMutableString new] autorelease];
    NSArray *       theNames;
    CFIndex         nameIndex;
    CFIndex         numOfNames;
 
    [theDescriptionStr appendFormat:@"%@", [self lineageDescriptionOfUIElement:element]];
    
    // display attributes
    theNames = [UIElementUtilities attributeNamesOfUIElement:element];
    if (theNames) {
    
        numOfNames = [theNames count];
        
        if (numOfNames)
            [theDescriptionStr appendString:@"\nAttributes:\n"];
 
        for( nameIndex = 0; nameIndex < numOfNames; nameIndex++ ) {
            
            NSString *  theName = NULL;
            id      theValue = NULL;
            Boolean theSettableFlag = false;
            
            // Grab name
            theName = [theNames objectAtIndex:nameIndex];
                
            // Grab settable field
            AXUIElementIsAttributeSettable( element, (CFStringRef)theName, &theSettableFlag );
            
            // Add string        
            [theDescriptionStr appendFormat:@"   %@%@:  “%@”\n", theName, (theSettableFlag?@" (W)":@""), [self descriptionForUIElement:element attribute:theName beingVerbose:false]];
        
            [theValue release];
        }
    
    }
    
    // display actions
    theNames = [UIElementUtilities actionNamesOfUIElement:element];
    if (theNames) {
    
        numOfNames = [theNames count];
        
        if (numOfNames)
            [theDescriptionStr appendString:@"\nActions:\n"];
 
        for( nameIndex = 0; nameIndex < numOfNames; nameIndex++ ) {
            
            NSString *  theName         = NULL;
            NSString *  theDesc         = NULL;
            
            // Grab name
            theName = [theNames objectAtIndex:nameIndex];
            
            // Grab description
        theDesc = [self descriptionOfAction:theName ofUIElement:element];
            
            // Add string        
            [theDescriptionStr appendFormat:@"   %@ - %@\n", theName, theDesc];
        }
    
    }
    
    return theDescriptionStr;
}
 
 
// -------------------------------------------------------------------------------
//  descriptionForUIElement:uiElement:beingVerbose
//
//  Return a descripting string (role and title) of the given uiElement (AXUIElementRef).
// -------------------------------------------------------------------------------
+ (NSString *)descriptionForUIElement:(AXUIElementRef)uiElement attribute:(NSString *)name beingVerbose:(BOOL)beVerbose
{
    NSString *  theValueDescString  = NULL;
    CFTypeRef   theValue;
    CFIndex count;
    if (([name isEqualToString:NSAccessibilityChildrenAttribute]
            ||
         [name isEqualToString:NSAccessibilityRowsAttribute]
        )
            &&
        AXUIElementGetAttributeValueCount(uiElement, (CFStringRef)name, &count) == kAXErrorSuccess) {
        // No need to get the value of large arrays - we just display their size.
        // We don't want to do this with every attribute because AXUIElementGetAttributeValueCount on non-array valued
        // attributes will cause debug spewage.
        theValueDescString = [NSString stringWithFormat:@"<array of size %d>", count];
    } else if (AXUIElementCopyAttributeValue ( uiElement, (CFStringRef)name, &theValue ) == kAXErrorSuccess && theValue) {
        theValueDescString = [self descriptionOfValue:theValue beingVerbose:beVerbose];
    }
    return theValueDescString;
}
 
// This method returns a 'no description' string by default
+ (NSString *)descriptionOfAXDescriptionOfUIElement:(AXUIElementRef)element {
    id result = [self valueOfAttribute:NSAccessibilityDescriptionAttribute ofUIElement:element];
    return (!result || [result isEqualToString:@""]) ? UIElementUtilitiesNoDescription: [result description];
}
 
 
 
 
 
@end


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