想知道是否有人可以举例说明如何下载文件以用于此 PDF 阅读器代码？我很新，一直在努力，但我认为是时候看看有经验的眼睛了。谢谢！
//
// ReaderViewController.m
// Reader v2.6.0
/////////////////////////////
#import "ReaderConstants.h"
#import "ReaderViewController.h"
#import "ThumbsViewController.h"
#import "ReaderMainToolbar.h"
#import "ReaderMainPagebar.h"
#import "ReaderContentView.h"
#import "ReaderThumbCache.h"
#import "ReaderThumbQueue.h"
#import <MessageUI/MessageUI.h>
@interface ReaderViewController () <UIScrollViewDelegate, UIGestureRecognizerDelegate, MFMailComposeViewControllerDelegate,
ReaderMainToolbarDelegate, ReaderMainPagebarDelegate, ReaderContentViewDelegate, ThumbsViewControllerDelegate>
@end
@implementation ReaderViewController
{
ReaderDocument *document;
UIScrollView *theScrollView;
ReaderMainToolbar *mainToolbar;
ReaderMainPagebar *mainPagebar;
NSMutableDictionary *contentViews;
UIPrintInteractionController *printInteraction;
NSInteger currentPage;
CGSize lastAppearSize;
NSDate *lastHideTime;
BOOL isVisible;
}
#pragma mark Constants
#define PAGING_VIEWS 3
#define TOOLBAR_HEIGHT 44.0f
#define PAGEBAR_HEIGHT 48.0f
#define TAP_AREA_SIZE 48.0f
#pragma mark Properties
@synthesize delegate;
#pragma mark Support methods
- (void)updateScrollViewContentSize
{
NSInteger count = [document.pageCount integerValue];
if (count > PAGING_VIEWS) count = PAGING_VIEWS; // Limit
CGFloat contentHeight = theScrollView.bounds.size.height;
CGFloat contentWidth = (theScrollView.bounds.size.width * count);
theScrollView.contentSize = CGSizeMake(contentWidth, contentHeight);
}
- (void)updateScrollViewContentViews
{
[self updateScrollViewContentSize]; // Update the content size
NSMutableIndexSet *pageSet = [NSMutableIndexSet indexSet]; // Page set
[contentViews enumerateKeysAndObjectsUsingBlock: // Enumerate content views
^(id key, id object, BOOL *stop)
{
ReaderContentView *contentView = object; [pageSet addIndex:contentView.tag];
}
];
__block CGRect viewRect = CGRectZero; viewRect.size = theScrollView.bounds.size;
__block CGPoint contentOffset = CGPointZero; NSInteger page = [document.pageNumber integerValue];
[pageSet enumerateIndexesUsingBlock: // Enumerate page number set
^(NSUInteger number, BOOL *stop)
{
NSNumber *key = [NSNumber numberWithInteger:number]; // # key
ReaderContentView *contentView = [contentViews objectForKey:key];
contentView.frame = viewRect; if (page == number) contentOffset = viewRect.origin;
viewRect.origin.x += viewRect.size.width; // Next view frame position
}
];
if (CGPointEqualToPoint(theScrollView.contentOffset, contentOffset) == false)
{
theScrollView.contentOffset = contentOffset; // Update content offset
}
}
- (void)updateToolbarBookmarkIcon
{
NSInteger page = [document.pageNumber integerValue];
BOOL bookmarked = [document.bookmarks containsIndex:page];
[mainToolbar setBookmarkState:bookmarked]; // Update
}
- (void)showDocumentPage:(NSInteger)page
{
if (page != currentPage) // Only if different
{
NSInteger minValue; NSInteger maxValue;
NSInteger maxPage = [document.pageCount integerValue];
NSInteger minPage = 1;
if ((page < minPage) || (page > maxPage)) return;
if (maxPage <= PAGING_VIEWS) // Few pages
{
minValue = minPage;
maxValue = maxPage;
}
else // Handle more pages
{
minValue = (page - 1);
maxValue = (page + 1);
if (minValue < minPage)
{minValue++; maxValue++;}
else
if (maxValue > maxPage)
{minValue--; maxValue--;}
}
NSMutableIndexSet *newPageSet = [NSMutableIndexSet new];
NSMutableDictionary *unusedViews = [contentViews mutableCopy];
CGRect viewRect = CGRectZero; viewRect.size = theScrollView.bounds.size;
for (NSInteger number = minValue; number <= maxValue; number++)
{
NSNumber *key = [NSNumber numberWithInteger:number]; // # key
ReaderContentView *contentView = [contentViews objectForKey:key];
if (contentView == nil) // Create a brand new document content view
{
NSURL *fileURL = document.fileURL; NSString *phrase = document.password; // Document properties
contentView = [[ReaderContentView alloc] initWithFrame:viewRect fileURL:fileURL page:number password:phrase];
[theScrollView addSubview:contentView]; [contentViews setObject:contentView forKey:key];
contentView.message = self; [newPageSet addIndex:number];
}
else // Reposition the existing content view
{
contentView.frame = viewRect; [contentView zoomReset];
[unusedViews removeObjectForKey:key];
}
viewRect.origin.x += viewRect.size.width;
}
[unusedViews enumerateKeysAndObjectsUsingBlock: // Remove unused views
^(id key, id object, BOOL *stop)
{
[contentViews removeObjectForKey:key];
ReaderContentView *contentView = object;
[contentView removeFromSuperview];
}
];
unusedViews = nil; // Release unused views
CGFloat viewWidthX1 = viewRect.size.width;
CGFloat viewWidthX2 = (viewWidthX1 * 2.0f);
CGPoint contentOffset = CGPointZero;
if (maxPage >= PAGING_VIEWS)
{
if (page == maxPage)
contentOffset.x = viewWidthX2;
else
if (page != minPage)
contentOffset.x = viewWidthX1;
}
else
if (page == (PAGING_VIEWS - 1))
contentOffset.x = viewWidthX1;
if (CGPointEqualToPoint(theScrollView.contentOffset, contentOffset) == false)
{
theScrollView.contentOffset = contentOffset; // Update content offset
}
if ([document.pageNumber integerValue] != page) // Only if different
{
document.pageNumber = [NSNumber numberWithInteger:page]; // Update page number
}
NSURL *fileURL = document.fileURL; NSString *phrase = document.password; NSString *guid = document.guid;
if ([newPageSet containsIndex:page] == YES) // Preview visible page first
{
NSNumber *key = [NSNumber numberWithInteger:page]; // # key
ReaderContentView *targetView = [contentViews objectForKey:key];
[targetView showPageThumb:fileURL page:page password:phrase guid:guid];
[newPageSet removeIndex:page]; // Remove visible page from set
}
[newPageSet enumerateIndexesWithOptions:NSEnumerationReverse usingBlock: // Show previews
^(NSUInteger number, BOOL *stop)
{
NSNumber *key = [NSNumber numberWithInteger:number]; // # key
ReaderContentView *targetView = [contentViews objectForKey:key];
[targetView showPageThumb:fileURL page:number password:phrase guid:guid];
}
];
newPageSet = nil; // Release new page set
[mainPagebar updatePagebar]; // Update the pagebar display
[self updateToolbarBookmarkIcon]; // Update bookmark
currentPage = page; // Track current page number
}
}
- (void)showDocument:(id)object
{
[self updateScrollViewContentSize]; // Set content size
[self showDocumentPage:[document.pageNumber integerValue]];
document.lastOpen = [NSDate date]; // Update last opened date
isVisible = YES; // iOS present modal bodge
}
#pragma mark UIViewController methods
- (id)initWithReaderDocument:(ReaderDocument *)object
{
id reader = nil; // ReaderViewController object
if ((object != nil) && ([object isKindOfClass:[ReaderDocument class]]))
{
if ((self = [super initWithNibName:nil bundle:nil])) // Designated initializer
{
NSNotificationCenter *notificationCenter = [NSNotificationCenter defaultCenter];
[notificationCenter addObserver:self selector:@selector(applicationWill:) name:UIApplicationWillTerminateNotification object:nil];
[notificationCenter addObserver:self selector:@selector(applicationWill:) name:UIApplicationWillResignActiveNotification object:nil];
[object updateProperties]; document = object; // Retain the supplied ReaderDocument object for our use
[ReaderThumbCache touchThumbCacheWithGUID:object.guid]; // Touch the document thumb cache directory
reader = self; // Return an initialized ReaderViewController object
}
}
return reader;
}
- (void)viewDidLoad
{
[super viewDidLoad];
assert(document != nil); // Must have a valid ReaderDocument
self.view.backgroundColor = [UIColor scrollViewTexturedBackgroundColor];
CGRect viewRect = self.view.bounds; // View controller's view bounds
theScrollView = [[UIScrollView alloc] initWithFrame:viewRect]; // All
theScrollView.scrollsToTop = NO;
theScrollView.pagingEnabled = YES;
theScrollView.delaysContentTouches = NO;
theScrollView.showsVerticalScrollIndicator = NO;
theScrollView.showsHorizontalScrollIndicator = NO;
theScrollView.contentMode = UIViewContentModeRedraw;
theScrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
theScrollView.backgroundColor = [UIColor clearColor];
theScrollView.userInteractionEnabled = YES;
theScrollView.autoresizesSubviews = NO;
theScrollView.delegate = self;
[self.view addSubview:theScrollView];
CGRect toolbarRect = viewRect;
toolbarRect.size.height = TOOLBAR_HEIGHT;
mainToolbar = [[ReaderMainToolbar alloc] initWithFrame:toolbarRect document:document]; // At top
mainToolbar.delegate = self;
[self.view addSubview:mainToolbar];
CGRect pagebarRect = viewRect;
pagebarRect.size.height = PAGEBAR_HEIGHT;
pagebarRect.origin.y = (viewRect.size.height - PAGEBAR_HEIGHT);
mainPagebar = [[ReaderMainPagebar alloc] initWithFrame:pagebarRect document:document]; // At bottom
mainPagebar.delegate = self;
[self.view addSubview:mainPagebar];
UITapGestureRecognizer *singleTapOne = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];
singleTapOne.numberOfTouchesRequired = 1; singleTapOne.numberOfTapsRequired = 1; singleTapOne.delegate = self;
[self.view addGestureRecognizer:singleTapOne];
UITapGestureRecognizer *doubleTapOne = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleDoubleTap:)];
doubleTapOne.numberOfTouchesRequired = 1; doubleTapOne.numberOfTapsRequired = 2; doubleTapOne.delegate = self;
[self.view addGestureRecognizer:doubleTapOne];
UITapGestureRecognizer *doubleTapTwo = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleDoubleTap:)];
doubleTapTwo.numberOfTouchesRequired = 2; doubleTapTwo.numberOfTapsRequired = 2; doubleTapTwo.delegate = self;
[self.view addGestureRecognizer:doubleTapTwo];
[singleTapOne requireGestureRecognizerToFail:doubleTapOne]; // Single tap requires double tap to fail
contentViews = [NSMutableDictionary new]; lastHideTime = [NSDate date];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
if (CGSizeEqualToSize(lastAppearSize, CGSizeZero) == false)
{
if (CGSizeEqualToSize(lastAppearSize, self.view.bounds.size) == false)
{
[self updateScrollViewContentViews]; // Update content views
}
lastAppearSize = CGSizeZero; // Reset view size tracking
}
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
if (CGSizeEqualToSize(theScrollView.contentSize, CGSizeZero)) // First time
{
[self performSelector:@selector(showDocument:) withObject:nil afterDelay:0.02];
}
#if (READER_DISABLE_IDLE == TRUE) // Option
[UIApplication sharedApplication].idleTimerDisabled = YES;
#endif // end of READER_DISABLE_IDLE Option
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
lastAppearSize = self.view.bounds.size; // Track view size
#if (READER_DISABLE_IDLE == TRUE) // Option
[UIApplication sharedApplication].idleTimerDisabled = NO;
#endif // end of READER_DISABLE_IDLE Option
}
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
}
- (void)viewDidUnload
{
#ifdef DEBUG
NSLog(@"%s", __FUNCTION__);
#endif
mainToolbar = nil; mainPagebar = nil;
theScrollView = nil; contentViews = nil; lastHideTime = nil;
lastAppearSize = CGSizeZero; currentPage = 0;
[super viewDidUnload];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
if (isVisible == NO) return; // iOS present modal bodge
if ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPad)
{
if (printInteraction != nil) [printInteraction dismissAnimated:NO];
}
}
- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation duration:(NSTimeInterval)duration
{
if (isVisible == NO) return; // iOS present modal bodge
[self updateScrollViewContentViews]; // Update content views
lastAppearSize = CGSizeZero; // Reset view size tracking
}
/*
- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
//if (isVisible == NO) return; // iOS present modal bodge
//if (fromInterfaceOrientation == self.interfaceOrientation) return;
}
*/
- (void)didReceiveMemoryWarning
{
#ifdef DEBUG
NSLog(@"%s", __FUNCTION__);
#endif
[super didReceiveMemoryWarning];
}
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
#pragma mark UIScrollViewDelegate methods
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
__block NSInteger page = 0;
CGFloat contentOffsetX = scrollView.contentOffset.x;
[contentViews enumerateKeysAndObjectsUsingBlock: // Enumerate content views
^(id key, id object, BOOL *stop)
{
ReaderContentView *contentView = object;
if (contentView.frame.origin.x == contentOffsetX)
{
page = contentView.tag; *stop = YES;
}
}
];
if (page != 0) [self showDocumentPage:page]; // Show the page
}
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView
{
[self showDocumentPage:theScrollView.tag]; // Show page
theScrollView.tag = 0; // Clear page number tag
}
#pragma mark UIGestureRecognizerDelegate methods
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)recognizer shouldReceiveTouch:(UITouch *)touch
{
if ([touch.view isKindOfClass:[UIScrollView class]]) return YES;
return NO;
}
#pragma mark UIGestureRecognizer action methods
- (void)decrementPageNumber
{
if (theScrollView.tag == 0) // Scroll view did end
{
NSInteger page = [document.pageNumber integerValue];
NSInteger maxPage = [document.pageCount integerValue];
NSInteger minPage = 1; // Minimum
if ((maxPage > minPage) && (page != minPage))
{
CGPoint contentOffset = theScrollView.contentOffset;
contentOffset.x -= theScrollView.bounds.size.width; // -= 1
[theScrollView setContentOffset:contentOffset animated:YES];
theScrollView.tag = (page - 1); // Decrement page number
}
}
}
- (void)incrementPageNumber
{
if (theScrollView.tag == 0) // Scroll view did end
{
NSInteger page = [document.pageNumber integerValue];
NSInteger maxPage = [document.pageCount integerValue];
NSInteger minPage = 1; // Minimum
if ((maxPage > minPage) && (page != maxPage))
{
CGPoint contentOffset = theScrollView.contentOffset;
contentOffset.x += theScrollView.bounds.size.width; // += 1
[theScrollView setContentOffset:contentOffset animated:YES];
theScrollView.tag = (page + 1); // Increment page number
}
}
}
- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer
{
if (recognizer.state == UIGestureRecognizerStateRecognized)
{
CGRect viewRect = recognizer.view.bounds; // View bounds
CGPoint point = [recognizer locationInView:recognizer.view];
CGRect areaRect = CGRectInset(viewRect, TAP_AREA_SIZE, 0.0f); // Area
if (CGRectContainsPoint(areaRect, point)) // Single tap is inside the area
{
NSInteger page = [document.pageNumber integerValue]; // Current page #
NSNumber *key = [NSNumber numberWithInteger:page]; // Page number key
ReaderContentView *targetView = [contentViews objectForKey:key];
id target = [targetView processSingleTap:recognizer]; // Target
if (target != nil) // Handle the returned target object
{
if ([target isKindOfClass:[NSURL class]]) // Open a URL
{
NSURL *url = (NSURL *)target; // Cast to a NSURL object
if (url.scheme == nil) // Handle a missing URL scheme
{
NSString *www = url.absoluteString; // Get URL string
if ([www hasPrefix:@"www"] == YES) // Check for 'www' prefix
{
NSString *http = [NSString stringWithFormat:@"http://%@", www];
url = [NSURL URLWithString:http]; // Proper http-based URL
}
}
if ([[UIApplication sharedApplication] openURL:url] == NO)
{
#ifdef DEBUG
NSLog(@"%s '%@'", __FUNCTION__, url); // Bad or unknown URL
#endif
}
}
else // Not a URL, so check for other possible object type
{
if ([target isKindOfClass:[NSNumber class]]) // Goto page
{
NSInteger value = [target integerValue]; // Number
[self showDocumentPage:value]; // Show the page
}
}
}
else // Nothing active tapped in the target content view
{
if ([lastHideTime timeIntervalSinceNow] < -0.75) // Delay since hide
{
if ((mainToolbar.hidden == YES) || (mainPagebar.hidden == YES))
{
[mainToolbar showToolbar]; [mainPagebar showPagebar]; // Show
}
}
}
return;
}
CGRect nextPageRect = viewRect;
nextPageRect.size.width = TAP_AREA_SIZE;
nextPageRect.origin.x = (viewRect.size.width - TAP_AREA_SIZE);
if (CGRectContainsPoint(nextPageRect, point)) // page++ area
{
[self incrementPageNumber]; return;
}
CGRect prevPageRect = viewRect;
prevPageRect.size.width = TAP_AREA_SIZE;
if (CGRectContainsPoint(prevPageRect, point)) // page-- area
{
[self decrementPageNumber]; return;
}
}
}
- (void)handleDoubleTap:(UITapGestureRecognizer *)recognizer
{
if (recognizer.state == UIGestureRecognizerStateRecognized)
{
CGRect viewRect = recognizer.view.bounds; // View bounds
CGPoint point = [recognizer locationInView:recognizer.view];
CGRect zoomArea = CGRectInset(viewRect, TAP_AREA_SIZE, TAP_AREA_SIZE);
if (CGRectContainsPoint(zoomArea, point)) // Double tap is in the zoom area
{
NSInteger page = [document.pageNumber integerValue]; // Current page #
NSNumber *key = [NSNumber numberWithInteger:page]; // Page number key
ReaderContentView *targetView = [contentViews objectForKey:key];
switch (recognizer.numberOfTouchesRequired) // Touches count
{
case 1: // One finger double tap: zoom ++
{
[targetView zoomIncrement]; break;
}
case 2: // Two finger double tap: zoom --
{
[targetView zoomDecrement]; break;
}
}
return;
}
CGRect nextPageRect = viewRect;
nextPageRect.size.width = TAP_AREA_SIZE;
nextPageRect.origin.x = (viewRect.size.width - TAP_AREA_SIZE);
if (CGRectContainsPoint(nextPageRect, point)) // page++ area
{
[self incrementPageNumber]; return;
}
CGRect prevPageRect = viewRect;
prevPageRect.size.width = TAP_AREA_SIZE;
if (CGRectContainsPoint(prevPageRect, point)) // page-- area
{
[self decrementPageNumber]; return;
}
}
}
#pragma mark ReaderContentViewDelegate methods
- (void)contentView:(ReaderContentView *)contentView touchesBegan:(NSSet *)touches
{
if ((mainToolbar.hidden == NO) || (mainPagebar.hidden == NO))
{
if (touches.count == 1) // Single touches only
{
UITouch *touch = [touches anyObject]; // Touch info
CGPoint point = [touch locationInView:self.view]; // Touch location
CGRect areaRect = CGRectInset(self.view.bounds, TAP_AREA_SIZE, TAP_AREA_SIZE);
if (CGRectContainsPoint(areaRect, point) == false) return;
}
[mainToolbar hideToolbar]; [mainPagebar hidePagebar]; // Hide
lastHideTime = [NSDate date];
}
}
#pragma mark ReaderMainToolbarDelegate methods
- (void)tappedInToolbar:(ReaderMainToolbar *)toolbar doneButton:(UIButton *)button
{
#if (READER_STANDALONE == FALSE) // Option
[document saveReaderDocument]; // Save any ReaderDocument object changes
[[ReaderThumbQueue sharedInstance] cancelOperationsWithGUID:document.guid];
[[ReaderThumbCache sharedInstance] removeAllObjects]; // Empty the thumb cache
if (printInteraction != nil) [printInteraction dismissAnimated:NO]; // Dismiss
if ([delegate respondsToSelector:@selector(dismissReaderViewController:)] == YES)
{
[delegate dismissReaderViewController:self]; // Dismiss the ReaderViewController
}
else // We have a "Delegate must respond to -dismissReaderViewController: error"
{
NSAssert(NO, @"Delegate must respond to -dismissReaderViewController:");
}
#endif // end of READER_STANDALONE Option
}