Notes of a Developer » objective-c

NSTableView with custom header

Vladimir Boychentsov — Sun, 22 Jan 2012 12:04:16 +0000

Default header looks like this

First we want change height of header:

1 2	NSTableHeaderView *tableHeaderView = [[NSTableHeaderView alloc] initWithFrame:NSMakeRect(0, 0, 120, 60)]; [_tableView setHeaderView:tableHeaderView];

Next step we want change NSTableHeaderCell, can make category for this class or make subclass. So, I wrote subclass.

Empty category

Rewrite method for change style

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@implementation NSTableHeaderCell (VBNSTableHeaderCell)

- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView {

NSMutableParagraphStyle * aParagraphStyle = [[NSMutableParagraphStyle alloc] init];
[aParagraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
[aParagraphStyle setAlignment:NSCenterTextAlignment];
NSMutableDictionary *attrs = [[NSMutableDictionary dictionaryWithDictionary:
[[self attributedStringValue]
attributesAtIndex:0
effectiveRange:NULL]]
mutableCopy];
[attrs setObject:aParagraphStyle forKey:NSParagraphStyleAttributeName];

NSGradient *grayGradient = [[NSGradient alloc] initWithColorsAndLocations: [NSColor colorWithDeviceWhite:0.95 alpha:1], 0.1,
[NSColor colorWithDeviceWhite:0.5 alpha:1], 0.9, nil];
[grayGradient drawInRect:cellFrame angle:90];

[[self stringValue] drawInRect:cellFrame withAttributes:attrs];
}
@end

ScrollView with scroll’s indicators, which are shown all the time.

Vladimir Boychentsov — Thu, 22 Dec 2011 09:53:13 +0000

My simple solution by writing category for UIImageView, because scroller is imageview.

How to use :)
Just setup tag for your scrollview and you will get one with scroll indicators, which are shown all the time.

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#define noDisableVerticalScrollTag 836913
#define noDisableHorizontalScrollTag 836914

@implementation UIImageView (ForScrollView)

- (void) setAlpha:(float)alpha {

if (self.superview.tag == noDisableVerticalScrollTag) {
if (alpha == 0 && self.autoresizingMask == UIViewAutoresizingFlexibleLeftMargin) {
if (self.frame.size.width < 10 && self.frame.size.height > self.frame.size.width) {
UIScrollView *sc = (UIScrollView*)self.superview;
if (sc.frame.size.height < sc.contentSize.height) {
return;
}
}
}
}

if (self.superview.tag == noDisableHorizontalScrollTag) {
if (alpha == 0 && self.autoresizingMask == UIViewAutoresizingFlexibleTopMargin) {
if (self.frame.size.height < 10 && self.frame.size.height < self.frame.size.width) {
UIScrollView *sc = (UIScrollView*)self.superview;
if (sc.frame.size.width < sc.contentSize.width) {
return;
}
}
}
}

[super setAlpha:alpha];
}
@end

If you want both scroll it’s easy to change code.

NSRegularExpression sample for comment syntax highlighting

Vladimir Boychentsov — Tue, 08 Nov 2011 00:25:10 +0000

I have this text:

1	word1 word2 " word3 //" word4

I wrote simple solution. I know it can be better. I know about Back Reference, but i don’t have experience with it.

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NSRegularExpression *expression = [NSRegularExpression regularExpressionWithPattern:@"((@\"|\").*?(\"))"
options:NSRegularExpressionDotMatchesLineSeparators
error:nil];
NSArray *textArray = [expression matchesInString:textString options:0 range:NSMakeRange(0, [textString length])];

for (NSTextCheckingResult *result in textArray) {
// set color for range
}

// Comments
expression = [NSRegularExpression regularExpressionWithPattern:@"(//[^\"\n]*)"
options:0
error:nil];

NSArray * arrayComments = [expression matchesInString:textString options:0 range:NSMakeRange(0, [textString length])];

for (NSTextCheckingResult *resultComment in arrayComments) {

BOOL inside = NO;
for (NSTextCheckingResult *resultText in textArray) {
NSInteger from = resultText.range.location;
NSInteger to = resultText.range.location+resultText.range.length;
NSInteger now = resultComment.range.location;
if (from < now && now < to) {
inside = YES;
break;
}
}
if (!inside) {
// set color for range
}
}

Simple EKDemo – EKEvent

Vladimir Boychentsov — Sun, 06 Nov 2011 00:28:57 +0000

Now we have controller for creating events. This controller included from 4.0 iOS SDK.

SimpleEKDemo

The application uses table views to display EKCalendar object and EKEvent objects retrieved from an EKEventStore object. It implements EKEventViewController for viewing and editing existing EKEvents, and uses EKEventEditViewController for creating new EKEvents.

My Custom UITextView with syntax highlighting

Vladimir Boychentsov — Sat, 05 Nov 2011 00:51:21 +0000

Color Picker for iOS

Vladimir Boychentsov — Sat, 29 Oct 2011 12:17:25 +0000

Example:

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- (void)viewDidLoad
{
[super viewDidLoad];

// Do any additional setup after loading the view, typically from a nib.

if (self.cPicker == nil) {
[self.view setBackgroundColor:[UIColor grayColor]];
self.cPicker = [[VBColorPicker alloc] initWithFrame:CGRectMake(0, 0, 202, 202)];
[_cPicker setCenter:self.view.center];
[self.view addSubview:_cPicker];
[_cPicker setDelegate:self];
[_cPicker showPicker];

// set default YES!
[_cPicker setHideAfterSelection:NO];
}

}

// set color from picker
- (void) pickedColor:(UIColor *)color {
[_rect setBackgroundColor:color];
[_cPicker hidePicker];
}

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if (![_cPicker isHidden]) {
[_cPicker hidePicker];
}
}

// show picker by double touch
- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];

if (touch.tapCount == 2) {
[_cPicker setCenter:[touch locationInView:self.view]];
[_cPicker showPicker];
}
}

Sorting by block

Vladimir Boychentsov — Sat, 22 Oct 2011 19:17:30 +0000

Sorting by block

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NSArray *stringsArray = [NSArray arrayWithObjects:
@"string 1",
@"String 21",
@"string 12",
@"String 11",
@"String 02", nil];

static NSStringCompareOptions comparisonOptions = NSCaseInsensitiveSearch | NSNumericSearch |
NSWidthInsensitiveSearch | NSForcedOrderingSearch;
NSLocale *currentLocale = [NSLocale currentLocale];

NSComparator finderSortBlock = ^(id string1, id string2) {

NSRange string1Range = NSMakeRange(0, [string1 length]);
return [string1 compare:string2 options:comparisonOptions range:string1Range locale:currentLocale];
};

NSArray *finderSortArray = [stringsArray sortedArrayUsingComparator:finderSortBlock];
NSLog(@"finderSortArray: %@", finderSortArray);

Result:
/*
Output:
finderSortArray: (
“string 1″,
“String 02″,
“String 11″,
“string 12″,
“String 21″
)
*/

Tweeting – example of Apple

Vladimir Boychentsov — Wed, 05 Oct 2011 11:51:43 +0000

Tweeting

Get Geo tags from image

Vladimir Boychentsov — Wed, 17 Aug 2011 22:22:44 +0000

Little application for getting geo location from photo

Download Application

Administrator Privilege in Mac OS X app

Vladimir Boychentsov — Wed, 17 Aug 2011 20:17:49 +0000

If the Terminal command requires Administrator Privilege (aka sudo), use AuthorizationExecuteWithPrivileges instead. The following will create a file named “com.developers-life.test” is the root directory “/System/Library/Caches”.

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AuthorizationRef authorizationRef;
FILE *pipe = NULL;
OSStatus err = AuthorizationCreate(nil,
kAuthorizationEmptyEnvironment,
kAuthorizationFlagDefaults,
&authorizationRef);

char *command= "/usr/bin/touch";
char *args[] = {"/System/Library/Caches/com.developers-life.test", nil};

err = AuthorizationExecuteWithPrivileges(authorizationRef,
command,
kAuthorizationFlagDefaults,
args,
&pipe);