我需要让我的应用程序从 Safari 和邮件应用程序打开文档，并在 UIDocumentInteractionController 中使用“打开方式...”类(class)。我该如何实现？

最佳答案

我知道这对我作为一个初级程序员，或者现在作为一个中等技能的程序员来说是非常令人沮丧的。通过 Mail 和 Safari 应用程序进行的文件 I/O 涉及非常……有趣的应用程序本身命名约定。因此，让我们动手做一个 iPhone 的 Xcode 项目。打开 Xcode(我将在本教程中使用 4.2)并选择“单一 View ”应用程序模板(或创建一个空项目，然后添加一个带有 .xib 的单一 View )。



在那个新创建的应用程序中，将 View Controller (和关联的 xib)重命名为 OfflineReaderViewController ，然后我们将深入研究代码。 (我们将触及除前缀头文件和 main.m 之外的每个文件，因此请注意，您将需要前面的所有文件!)

输入 AppDelegate header 并将以下代码粘贴到其中:

#import <UIKit/UIKit.h>

@class OfflineReaderViewController;

@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;

@property (strong, nonatomic) OfflineReaderViewController *viewController;

@end

#import "AppDelegate.h"
#import "OfflineReaderViewController.h"

@implementation AppDelegate

@synthesize window;
@synthesize viewController;

-(BOOL)application:(UIApplication *)application 
           openURL:(NSURL *)url 
 sourceApplication:(NSString *)sourceApplication 
        annotation:(id)annotation 
{    
    // Make sure url indicates a file (as opposed to, e.g., http://)
    if (url != nil && [url isFileURL]) {
        // Tell our OfflineReaderViewController to process the URL
        [self.viewController handleDocumentOpenURL:url];
    }
    // Indicate that we have successfully opened the URL
    return YES;
}

- (void)dealloc
{
    [window release];
    [viewController release];
    [super dealloc];
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    // Override point for customization after application launch.
    self.viewController = [[[OfflineReaderViewController alloc] initWithNibName:@"ViewController" bundle:nil] autorelease];
    self.window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];
    return YES;
}

- (void)applicationWillResignActive:(UIApplication *)application
{
    /*
     Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
     Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
     */
}

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    /*
     Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later. 
     If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
     */
}

- (void)applicationWillEnterForeground:(UIApplication *)application
{
    /*
     Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
     */
}

- (void)applicationDidBecomeActive:(UIApplication *)application
{
    /*
     Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
     */
}

- (void)applicationWillTerminate:(UIApplication *)application
{
    /*
     Called when the application is about to terminate.
     Save data if appropriate.
     See also applicationDidEnterBackground:.
     */
}

@end

-(BOOL)application:(UIApplication *)application 
               openURL:(NSURL *)url 
     sourceApplication:(NSString *)sourceApplication 
            annotation:(id)annotation 
    {    
        if (url != nil && [url isFileURL]) {
            [self.viewController handleDocumentOpenURL:url];
        }    
        return YES;
    }

#import <UIKit/UIKit.h>

@interface OfflineReaderViewController : UIViewController 
<UIDocumentInteractionControllerDelegate> {
    IBOutlet UIWebView *webView;
}

-(void)openDocumentIn;
-(void)handleDocumentOpenURL:(NSURL *)url;
-(void)displayAlert:(NSString *) str;
-(void)loadFileFromDocumentsFolder:(NSString *) filename;
-(void)listFilesFromDocumentsFolder;

- (IBAction) btnDisplayFiles;

@end

#import "OfflineReaderViewController.h"

@implementation OfflineReaderViewController

UIDocumentInteractionController *documentController;

-(void)openDocumentIn {    
    NSString * filePath = 
    [[NSBundle mainBundle] 
     pathForResource:@"Minore" ofType:@"pdf"];    
    documentController = 
    [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:filePath]];
    documentController.delegate = self;
    [documentController retain];
    documentController.UTI = @"com.adobe.pdf";
    [documentController presentOpenInMenuFromRect:CGRectZero 
                                           inView:self.view 
                                         animated:YES];
}

-(void)documentInteractionController:(UIDocumentInteractionController *)controller 
       willBeginSendingToApplication:(NSString *)application {

}

-(void)documentInteractionController:(UIDocumentInteractionController *)controller 
          didEndSendingToApplication:(NSString *)application {

}

-(void)documentInteractionControllerDidDismissOpenInMenu:
(UIDocumentInteractionController *)controller {

}
-(void) displayAlert:(NSString *) str {
    UIAlertView *alert = 
    [[UIAlertView alloc] initWithTitle:@"Alert" 
                               message:str 
                              delegate:self
                     cancelButtonTitle:@"OK"
                     otherButtonTitles:nil];
    [alert show];
    [alert release];    
}

- (void)handleDocumentOpenURL:(NSURL *)url {
    [self displayAlert:[url absoluteString]];
    NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];        
    [webView setUserInteractionEnabled:YES];    
    [webView loadRequest:requestObj];
}


-(void)loadFileFromDocumentsFolder:(NSString *) filename {
    //---get the path of the Documents folder---   
    NSArray *paths = NSSearchPathForDirectoriesInDomains(  
                                                         NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0];     
    NSString *filePath = [documentsDirectory 
                          stringByAppendingPathComponent:filename];    
    NSURL *fileUrl = [NSURL fileURLWithPath:filePath];        
    [self handleDocumentOpenURL:fileUrl];
}

-(void)listFilesFromDocumentsFolder {    
    //---get the path of the Documents folder---    
    NSArray *paths = NSSearchPathForDirectoriesInDomains(     
                                                         NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 

    NSFileManager *manager = [NSFileManager defaultManager];
    NSArray *fileList =   
    [manager contentsOfDirectoryAtPath:documentsDirectory error:nil];
    NSMutableString *filesStr = 
    [NSMutableString stringWithString:@"Files in Documents folder \n"];
    for (NSString *s in fileList){    
        [filesStr appendFormat:@"%@ \n", s];
    }
    [self displayAlert:filesStr];    
    [self loadFileFromDocumentsFolder:@"0470918020.pdf"];
}

- (IBAction) btnDisplayFiles {
    [self listFilesFromDocumentsFolder];    
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle

- (void)viewDidLoad {
    [super viewDidLoad];
    [self openDocumentIn];
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
}

- (void)viewDidDisappear:(BOOL)animated
{
    [super viewDidDisappear:animated];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}

@end

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>CFBundleDevelopmentRegion</key>
    <string>en</string>
    <key>CFBundleDisplayName</key>
    <string>${PRODUCT_NAME}</string>
    <key>CFBundleExecutable</key>
    <string>${EXECUTABLE_NAME}</string>
    <key>CFBundleIconFiles</key>
    <array/>
    <key>CFBundleIdentifier</key>
    <string>CodaFi.${PRODUCT_NAME:rfc1034identifier}</string>
    <key>CFBundleInfoDictionaryVersion</key>
    <string>6.0</string>
    <key>CFBundleName</key>
    <string>${PRODUCT_NAME}</string>
    <key>CFBundlePackageType</key>
    <string>APPL</string>
    <key>CFBundleShortVersionString</key>
    <string>1.0</string>
    <key>CFBundleSignature</key>
    <string>????</string>
    <key>CFBundleVersion</key>
    <string>1.0</string>
    <key>LSRequiresIPhoneOS</key>
    <true/>
    <key>UIRequiredDeviceCapabilities</key>
    <array>
        <string>armv7</string>
    </array>
    <key>UISupportedInterfaceOrientations</key>
    <array>
        <string>UIInterfaceOrientationPortrait</string>
        <string>UIInterfaceOrientationLandscapeLeft</string>
        <string>UIInterfaceOrientationLandscapeRight</string>
    </array>
    <key>UIFileSharingEnabled</key>
    <true/>
    <key>CFBundleDocumentTypes</key>
    <array>
        <dict>
            <key>CFBundleTypeName</key>
            <string>PDF Document</string>
            <key>LSHandlerRank</key>
            <string>Alternate</string>
            <key>CFBundleTypeRole</key>
            <string>Viewer</string>
            <key>LSItemContentTypes</key>
            <array>
                <string>com.adobe.pdf</string>
            </array>
        </dict>
    </array>
</dict>
</plist>

关于objective-c - 支持在我的 iOS 邮件和 Safari 应用程序中打开...菜单项，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7942597/