What should I do if I want to display a specified page when opening a PDF document using PDF SDK for iOS?

To display a specified page when opening a PDF file, the interface [pdfViewCtrl gotoPage: (int) animated: (BOOL)] should be used. Foxit PDF SDK for iOS utilizes multi-thread to improve rendering speed, so please make sure the document has been loaded successfully before using the gotoPage interface.

The first one is that making a conditional statement in the openDoc interface to ensure that only when the document loading is complete, then call the gotoPage. If not, the gotoPage interface will not work, and the first page will be displayed. It is because the openDoc interface starts a new thread to perform the operation. Following is the sample code:. Following is the sample code:

#import "ViewController.h"
#import <foxitrdk /FSPDFViewControl.h>

@interface ViewController : UIViewController 
@end 
@implementation ViewController 
{
    FSPDFViewCtrl* pdfViewCtrl; 
} 
- (void)viewDidLoad {
    [super viewDidLoad];  

    // Get the path of a PDF. 
    NSString* pdfPath = [[NSBundle mainBundle] pathForResource:@"Sample" ofType:@"pdf"];  
    
    // Initilize a FSPDFViewCtrl object with the size of the entire screen. 
    pdfViewCtrl = [[FSPDFViewCtrl alloc] initWithFrame: [self.view bounds]];  

    // Open an unencrypted PDF document from a specified PDF file path, and go to the third page when completing the document loading.  
    [pdfViewCtrl openDoc:pdfPath password:nil completion:^(enum FSErrorCode error)

        { if(error == FSErrSuccess)  

            // Display the third page.  
            [pdfViewCtrl gotoPage:2 animated:NO];  
    }];  

    // Add the pdfView to the root view.  
    [self.view addSubview:pdfViewCtrl];  
} 
@end
</foxitrdk>

The second one is that implement the protocol, and then call the gotoPage interface in the onDocOpened event. Following is the sample code:

#import "ViewController.h"
#import <foxitrdk /FSPDFViewControl.h>

@interface ViewController : UIViewController
@end
@implementation ViewController
{
FSPDFViewCtrl* pdfViewCtrl;
}

- (void)viewDidLoad {
[super viewDidLoad];

// Get the path of a PDF
NSString* pdfPath = [[NSBundle mainBundle] pathForResource:@"Sample" ofType:@"pdf"];

// Initilize a FSPDFViewCtrl object with the size of the entire screen.
pdfViewCtrl = [[FSPDFViewCtrl alloc] initWithFrame: [self.view bounds]];

// Register the PDF document event listener.
[pdfViewCtrl registerDocEventListener:self];

// Open an unencrypted PDF document from a specified PDF file path.
[pdfViewCtrl openDoc:pdfPath password:nil completion:nil];

// Add the pdfView to the root view.
[self.view addSubview:pdfViewCtrl];

}
#pragma IDocEventListener
-(void)onDocOpened:(FSPDFDoc *)document error:(int)error
{
// display the third page.
[pdfViewCtrl gotoPage:2 animated:NO];
}
@end
</idoceventlistener></foxitrdk>