Changing a UITableView's scroll insets programmatically to reflect the size of an iPhone keyboard

iphone, sdk, uitableview

Solution

#pragma mark Keyboard Handling



- (void) viewDidAppear:(BOOL) ani {
    onscreen = YES;

    NSNotificationCenter* center = [NSNotificationCenter defaultCenter];
    [center addObserver:self selector:@selector(keyboardWillAppear:) name:UIKeyboardWillShowNotification object:nil];
    [center addObserver:self selector:@selector(keyboardDidAppear:) name:UIKeyboardDidShowNotification object:nil];
    [center addObserver:self selector:@selector(keyboardWillDisappear:) name:UIKeyboardWillHideNotification object:nil];
}

- (void) viewDidDisappear:(BOOL) ani {
    onscreen = NO;

    NSNotificationCenter* center = [NSNotificationCenter defaultCenter];
    [center removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [center removeObserver:self name:UIKeyboardDidShowNotification object:nil];
    [center removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

- (void) keyboardWillAppear:(NSNotification*) n {
    NSLog(@"Keyboard is about to appear");
}

- (void) keyboardDidAppear:(NSNotification*) n {

    CGRect bounds = [[[n userInfo] objectForKey:UIKeyboardBoundsUserInfoKey] CGRectValue];
    bounds = [self.view convertRect:bounds fromView:nil];

    CGRect tableFrame = searchResultsTable.frame;
    tableFrame.size.height -= bounds.size.height; // subtract the keyboard height
    if (self.tabBarController != nil) {
        tableFrame.size.height += 48; // add the tab bar height
    }

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(shrinkDidEnd:finished:contextInfo:)];
    searchResultsTable.frame = tableFrame;
    [UIView commitAnimations];

    //[self hideEditorView:currentEditorView];
    //[currentEditorView removeFromSuperview];
}

- (void) shrinkDidEnd:(NSString*) ident finished:(BOOL) finished contextInfo:(void*) nothing {
    NSIndexPath* sel = [searchResultsTable indexPathForSelectedRow];

    if (![[searchResultsTable indexPathsForVisibleRows] containsObject:sel])
    {
        [searchResultsTable scrollToNearestSelectedRowAtScrollPosition:UITableViewScrollPositionMiddle animated:YES];
    }
}

- (void) keyboardWillDisappear:(NSNotification*) n {
    CGRect bounds = [[[n userInfo] objectForKey:UIKeyboardBoundsUserInfoKey] CGRectValue];
    bounds = [self.view convertRect:bounds fromView:nil];

    CGRect tableFrame = searchResultsTable.frame;
    tableFrame.size.height += bounds.size.height; // add the keyboard height

    if (self.tabBarController != nil) {
        tableFrame.size.height -= 48; // subtract the tab bar height
    }

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(shrinkDidEnd:finished:contextInfo:)];
    searchResultsTable.frame = tableFrame;    
    [UIView commitAnimations];

    [searchResultsTable scrollToNearestSelectedRowAtScrollPosition:UITableViewScrollPositionMiddle animated:YES];
}

Problem

I know you can use the "Inset" property in Interface Builder to make a scroll view be inset from the main window so that it doesn't go below existing controls on the screen such as a tab bar, but how can you do this programmatically to adjust for when a keyboard is added to the screen? Currently my scroll view has cells under the keyboard that can't be reached because the view is still registering the bottom of the scroll view as the bottom of the phone, not the top of the keyboard.

Original source