2014/10/15 下午 10:04:51

iphone Programming Glossary: calculated

http://stackoverflow.com/questions/1052951/fuzzy-date-algorithm-in-objective-c

this it would be fairly simple to adapt the code you have given above to an Objective C Cocoa context. Since the delta calculated by NSDate is given in seconds given two dates you could easily adapt the code above Constants #define SECOND 1 #define MINUTE..

How to get a rotated, zoomed and panned image from an UIImageView at its full resolution?

http://stackoverflow.com/questions/11104042/how-to-get-a-rotated-zoomed-and-panned-image-from-an-uiimageview-at-its-full-re

code creates a snapshot of the enclosing view superview of faceImageView with clipsToBounds set to YES using a calculated scale factor. It assumes that the content mode of faceImageView is UIViewContentModeScaleAspectFit and that the frame of..

Using custom sections with NSFetchedResultsController?

http://stackoverflow.com/questions/1384345/using-custom-sections-with-nsfetchedresultscontroller

just have an attribute to sort by and use sectionNameKeyPath to generate the sections. But my sorting attribute is calculated on the fly and I can't seem to get the fetchedResultsController to use it correctly... Update Using jbrennan 's advice below..

How to get the RGB values for a pixel on an image on the iphone

http://stackoverflow.com/questions/144250/how-to-get-the-rgb-values-for-a-pixel-on-an-image-on-the-iphone

this version typedef struct RGBAPixel byte red byte green byte blue byte alpha RGBAPixel Bitmap function returns pre calculated RGBA divide RGB by A to get unmodified RGB RGBAPixel bitmap NSLog @ Returning bitmap representation of UIImage. 8 bits each..

How can I do variable height table cells on the iPhone properly?

http://stackoverflow.com/questions/1443335/how-can-i-do-variable-height-table-cells-on-the-iphone-properly

tableview heightForRowAtIndexPath I work out which item will be rendered for that cell and return the height that I calculated previously. As I said this works but calling sizeWithFont constrainedToSize is very slow when you're doing it for hundreds..

SQL Query for Performing Radius Search based on Latitude Longitude

http://stackoverflow.com/questions/1727137/sql-query-for-performing-radius-search-based-on-latitude-longitude

query. Personally I would calculate the TopLeft and BottomRight co ordinates of a square which only needs to be crudly calculated using pythagoras with sides equal to the range you are looking for and then perform the more complicated WHERE clause test..

Detecting which UIButton was pressed in a UITableView

http://stackoverflow.com/questions/1802707/detecting-which-uibutton-was-pressed-in-a-uitableview

forControlEvents UIControlEventTouchUpInside Then in touch handler touch coordinate retrieved and index path is calculated from that coordinate void checkButtonTapped id sender CGPoint buttonPosition sender convertPoint CGPointZero toView self.tableView..

dynamic calculation of UILabel width in UITableViewCell

http://stackoverflow.com/questions/1947970/dynamic-calculation-of-uilabel-width-in-uitableviewcell

textLabelSize.width 50 float detailTextFieldHeight cellFrame.size.height 1 NSLog @ detail text field calculated frame width height f f detailTextFieldWidth detailTextFieldHeight CGRect frame CGRectMake cellFrame.origin.x cellFrame.origin.y..

Zoom UILabel & Re-render font at correct size

http://stackoverflow.com/questions/1990458/zoom-uilabel-re-render-font-at-correct-size

contentSize of the scroll view to match the new size of the UILabel and use setContentOffset animated to set the newly calculated content offset with animated set to NO . It's a little tricky to get the math right but I do this when scaling text in one..

How to open call out MKAnnotationView programmatically? (iPhone, MapKit)

http://stackoverflow.com/questions/2193843/how-to-open-call-out-mkannotationview-programmatically-iphone-mapkit

on current location and walking the annotations available in the mv annotations array. Once the closest annotation is calculated call self openAnnotation closestAnnotation The mapView should scroll automatically to place your annotation in the center..

iPhone - dequeueReusableCellWithIdentifier usage

http://stackoverflow.com/questions/2928873/iphone-dequeuereusablecellwithidentifier-usage

memory usage to the exact number of cells it display whislt the method I use seems to favor speed as it keeps all calculated cells but can cause large memory consumption unless there's an inner limit to the queue . Am I wrong to use it this way..

Compensating compass lag with the gyroscope on iPhone 4

http://stackoverflow.com/questions/4212988/compensating-compass-lag-with-the-gyroscope-on-iphone-4

at this gravity.z value . It seems to me that I could synchronize the horizontal and magneticHeading values using a calculated horizontal value that maps to magneticHeading and synchronize the horizontal value to magneticHeading when I feel the compass..

UITableViewCell expand on click

http://stackoverflow.com/questions/4635338/uitableviewcell-expand-on-click

self.tableView beginUpdates self.tableView endUpdates Changes to the tableview cells' heights will automatically be calculated with heightForRowAtIndexPath and the changes will be animated too. In fact instead of a button on your cell that does this..

How to create custom easing function with Core Animation?

http://stackoverflow.com/questions/5161465/how-to-create-custom-easing-function-with-core-animation

work like this Lets describe the movement curve as a keyframe animation move t p where t is time 0..1 p is position calculated at time t . So move 0 returns the position at the start of curve move 0.5 the exact middle and move 1 at end. Using a an..

iOS UIImagePickerController result image orientation after upload

http://stackoverflow.com/questions/5427656/ios-uiimagepickercontroller-result-image-orientation-after-upload

case UIImageOrientationRight break Now we draw the underlying CGImage into a new context applying the transform calculated above. CGContextRef ctx CGBitmapContextCreate NULL self.size.width self.size.height CGImageGetBitsPerComponent self.CGImage..

How can I improve the performance of my custom OpenGL ES 2.0 depth texture generation?

http://stackoverflow.com/questions/6051237/how-can-i-improve-the-performance-of-my-custom-opengl-es-2-0-depth-texture-gener

The downside to this approach is that the depth values for each fragment of these impostor objects needs to be calculated in a fragment shader to be used when objects overlap. Unfortunately OpenGL ES 2.0 does not let you write to gl_FragDepth.. float distanceFromCenter length impostorSpaceCoordinate if distanceFromCenter 1.0 gl_FragColor vec4 1.0 else float calculatedDepth sqrt 1.0 distanceFromCenter distanceFromCenter mediump float currentDepthValue normalizedDepth adjustedSphereRadius.. sqrt 1.0 distanceFromCenter distanceFromCenter mediump float currentDepthValue normalizedDepth adjustedSphereRadius calculatedDepth Inlined color encoding for the depth values float ceiledValue ceil currentDepthValue 765.0 vec3 intDepthValue vec3..

how to display UIActivityIndicatorView BEFORE rotation begins

http://stackoverflow.com/questions/7041261/how-to-display-uiactivityindicatorview-before-rotation-begins

of do want to block the main thread to do my lifting. In the app I have a tableView all of whose heights need to be recalculated. When which is not a very common use case or I wouldn't even be considering this approach there are very many rows all the.. very common use case or I wouldn't even be considering this approach there are very many rows all the new heights are calculated and then cached during a tableView reloadData . If I farm the lifting off and let the rotate proceed then after the rotate..

Xcode/iOS5: Move UIView up, when keyboard appears

http://stackoverflow.com/questions/7952762/xcode-ios5-move-uiview-up-when-keyboard-appears

... Then change as needed when keyboard shows up self.view.center CGPointMake self.originalCenter.x new calculated y Finally restore it when keyboard is hidden self.view.center self.originalCenter Add animation sugar as you wish You have..

Is it possible to select the text rendered by Core Text in iPhone?

http://stackoverflow.com/questions/7979592/is-it-possible-to-select-the-text-rendered-by-core-text-in-iphone

1 CTLineGetTypographicBounds 2 CTLineGetStringRange 3 and CTLineGetOffsetForStringIndex 4 . The line rect can be calculated using the origin 1 ascent 2 descent 2 and offset 3 4 as shown bellow. lineRect CGRectMake origin.x offset origin.y descent..

Internal clock in iPhone background mode

http://stackoverflow.com/questions/9564823/internal-clock-in-iphone-background-mode

the OS changes the time itself according to info from cell towers. So in your case you can take the original time you calculated and modify it according to the modifications in kern.boottime. If you see kern.boottime changed significantly it may mean..