Print all rows of a table view when it's too large to fit on screen [closed]

Answer 1

I assume you're talking about printing using the iOS printing system, described in the “Printing” chapter of the Drawing and Printing Guide for iOS.

Since -[UITableView viewPrintFormatter] doesn't return a usable UIViewPrintFormatter, you have to find another way to do it. Let's write a function that turns a table view into a PDF:

static NSData *pdfDataWithTableView(UITableView *tableView) {

First, we'll save away the view's current bounds, so we can restore the bounds at the end.

    CGRect priorBounds = tableView.bounds;

Now we'll ask the table view to figure out how tall it needs to be to fit all of its rows.

    CGSize fittedSize = [tableView sizeThatFits:CGSizeMake(priorBounds.size.width, HUGE_VALF)];

And we'll go ahead and resize the table view to be that big. We also set its origin (which is the same as its contentOffset) to 0,0 so it will actually contain all of its rows.

    tableView.bounds = CGRectMake(0, 0, fittedSize.width, fittedSize.height);

We'll need a CGRect containing the bounds of our PDF page.

    // Standard US Letter dimensions 8.5" x 11"
    CGRect pdfPageBounds = CGRectMake(0, 0, 612, 792);

Now we can create a PDF graphics context.

    NSMutableData *pdfData = [[NSMutableData alloc] init];
    UIGraphicsBeginPDFContextToData(pdfData, pdfPageBounds, nil); {

We need to render the table view into the graphics context. Since the table view may be taller than the page size, we step the origin of the context down the Y axis in increments of the page height.

        for (CGFloat pageOriginY = 0; pageOriginY < fittedSize.height; pageOriginY += pdfPageBounds.size.height) {

We tell the context to begin a page.

            UIGraphicsBeginPDFPageWithInfo(pdfPageBounds, nil);

Since we're going to change the context's origin, we will save the graphics state and restore it after rendering this page.

            CGContextSaveGState(UIGraphicsGetCurrentContext()); {

Now we can adjust the origin of the context so that the top-left corner of the rendering area is at the appropriate point in our table view's coordinate system.

                CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0, -pageOriginY);

Finally we can tell the table view's layer to render itself to the context. Everything outside of the current page's bounds will be clipped away.

                [tableView.layer renderInContext:UIGraphicsGetCurrentContext()];

To clean up, we restore the graphics state.

            } CGContextRestoreGState(UIGraphicsGetCurrentContext());

At this point, if there are more pages, we'll go back to the top of the for loop.

        }

Now we've rendered all of the pages, so we can end the PDF graphics context.

    } UIGraphicsEndPDFContext();

And we need to restore the table view's bounds.

    tableView.bounds = priorBounds;

And finally we can return the PDF data.

    return pdfData;
}

Here it is all together:

static NSData *pdfDataWithTableView(UITableView *tableView) {
    CGRect priorBounds = tableView.bounds;
    CGSize fittedSize = [tableView sizeThatFits:CGSizeMake(priorBounds.size.width, HUGE_VALF)];
    tableView.bounds = CGRectMake(0, 0, fittedSize.width, fittedSize.height);

    // Standard US Letter dimensions 8.5" x 11"
    CGRect pdfPageBounds = CGRectMake(0, 0, 612, 792);

    NSMutableData *pdfData = [[NSMutableData alloc] init];
    UIGraphicsBeginPDFContextToData(pdfData, pdfPageBounds, nil); {
        for (CGFloat pageOriginY = 0; pageOriginY < fittedSize.height; pageOriginY += pdfPageBounds.size.height) {
            UIGraphicsBeginPDFPageWithInfo(pdfPageBounds, nil);
            CGContextSaveGState(UIGraphicsGetCurrentContext()); {
                CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0, -pageOriginY);
                [tableView.layer renderInContext:UIGraphicsGetCurrentContext()];
            } CGContextRestoreGState(UIGraphicsGetCurrentContext());
        }
    } UIGraphicsEndPDFContext();
    tableView.bounds = priorBounds;
    return pdfData;
}

You could of course use UIGraphicsBeginPDFContextToFile instead. That would use a lot less working memory.

Either way, once you have the PDF (in memory or in a file), you can use the iOS printing system to send it to a printer.