ThinhPhan

Example:
Input: 
@{
    1 = "A";
    2 = "B";
    3 = "C";
}

Output
@[

ThinhPhan

- (void)isImageDataValid:(NSURL *)imageURL
{
    dispatch_async(dispatch_queue_create("CheckImage", NULL), ^{
       
        NSData *data   = [NSData dataWithContentsOfURL:imageURL];
        UIImage *image = [UIImage imageWithData:data];
        if (image == nil) {
            // imageURL is not valid
            TLog(@"imageURL NOT valid: %@", imageURL);
        }

ThinhPhan

- (BOOL)isImageURLValid:(NSURL *)imageURL
{
    NSArray *imageExtensions = @[@"jpg", @"jpeg", @"png", @"gif", @"tiff"]; // Add more if you want
    NSString *extension = [imageURL pathExtension];
    
    for (NSString *ext in imageExtensions) {
        if ([ext isEqualToString:extension]) {
            return YES;
        }
    }

ThinhPhan

// 'Nothing' in Objective-C have a lot of meaning.
//	Read [nil / Nil / NULL / NSNull] http://nshipster.com/nil/
// With string, nothing can be nil or "" - empty string.

// Bad
if ([string isEqualToString:@""] && password == nil) {
}

// Good - Simple check 'length' for both conditions above.
if ([string length] == 0) {

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    CAShapeLayer *maskLayer = [CAShapeLayer layer];
    maskLayer.path = [UIBezierPath bezierPathWithRoundedRect:_quantityView.bounds
                                           byRoundingCorners:(UIRectCornerTopRight | UIRectCornerBottomRight) // Change your corner you want to round
                                                 cornerRadii:(CGSize){3.0f, 3.0f}].CGPath;
    myView.layer.mask = maskLayer;

ThinhPhan

I search a lot of questions and answers in SO. This is what i figure out. The result I want is map can zoom out to fit all/some annotations INCLUDE user's location.

The basic steps are:

• Calculate the min lat/long
• Calculate the max lat/long
• Create CLLocation objects for these two points
• Calculate distance between points
• Create region using center point between points and distance converted to degrees

ThinhPhan

#define ACCEPTABLE_CHARACTERS @"0123456789"
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    
    if (!string.length)
        return YES;
    
    if (textField == self.quantityTextField) {
        NSCharacterSet *numbersOnly = [[NSCharacterSet characterSetWithCharactersInString:ACCEPTABLE_CHARACTERS] invertedSet];
        NSString *filtered = [[string componentsSeparatedByCharactersInSet:numbersOnly] componentsJoinedByString:@""];
        BOOL stringIsValid = [string isEqualToString:filtered];

ThinhPhan

Making an IP camera with the Raspberry Pi

Including on-board motion detection

Requirements

• Raspberry Pi (512MB rev2 recommended)
• Raspberry Pi Camera board
• SD Card (min 2BG, 8GB recommended for good measure. Class 10)

Optionally, a wifi adapter verified to work with raspberry pi ( I used Edimax Wireless Nano USB Adapter - http://www.amazon.com/gp/product/B005CLMJLU/ )

ThinhPhan

Opt 1: From Nodesource

curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install -y nodejs

Opt 2: Download & Install

wget https://nodejs.org/dist/v4.3.2/node-v4.3.2-linux-armv6l.tar.gz 

ThinhPhan

.PHONY: install uninstall test set-default

test:
	sudo apt install plymouth-x11
	sudo plymouthd ; sudo plymouth --show-splash ; for ((I=0; I<10; I++)); do sleep 1 ; sudo plymouth --update=test$I ; done ; sudo plymouth --quit

uninstall:
	rm -rv /usr/share/plymouth/themes/first || true

install: uninstall