## Creating a Custom Input View

To create a custom input view, you'll need to create a new subclass of `UIView`. In this example, we'll create a simple view with 20 buttons arranged in a grid.

### Creating the Custom Input View Class

First, let's create the custom input view class:

```markdown
// CustomKeyboard.h

#import <UIKit/UIKit.h>

@interface CustomKeyboard : UIView

@end

// CustomKeyboard.m

#import "CustomKeyboard.h"

@implementation CustomKeyboard

- (instancetype)initWithBundle:(NSBundle *)bundle {
    self = [super init];
    if (self) {
        // Load the nib file
        NSArray *views = [[NSBundle mainBundle] loadNibNamed:@"CustomKeyboardView" owner:self options:nil];
        
        // Get the custom keyboard view from the array
        self.customKeyboardView = views.lastObject;
        
        // Set up the button layout
        [self setupButtonLayout];
    }
    
    return self;
}

- (void)setupButtonLayout {
    // Calculate the number of rows and columns based on the desired grid size
    const int numColumns = 4;
    const int numRows = 5;

    // Calculate the x and y coordinates for each button
    CGFloat buttonWidth = self.customKeyboardView.bounds.size.width / numColumns;
    CGFloat buttonHeight = self.customKeyboardView.bounds.size.height / numRows;

    for (int row = 0; row < numRows; row++) {
        for (int col = 0; col < numColumns; col++) {
            // Create a new button and add it to the view
            UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
            button.frame = CGRectMake(col * buttonWidth, row * buttonHeight, buttonWidth, buttonHeight);
            button.setTitle([NSString stringWithFormat:@"%d", row * numColumns + col], forState:UIControlStateNormal);
            [self.customKeyboardView addSubview:button];

            // Add a tap gesture recognizer to the button
            UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(buttonPressed:)];
            button.addGestureRecognizer(tapGestureRecognizer);
        }
    }

    self.customKeyboardView.backgroundColor = [UIColor grayColor];
}

- (void)buttonPressed:(UIGestureRecognizer *)gestureRecognizer {
    // Handle button press logic here
    NSLog(@"Button pressed!");
}

@end

## Integrating the Custom Input View with a UITextField

To integrate the custom input view with a `UITextField`, you'll need to set up the input view in the `viewDidLoad` method of your view controller.

### Introducing the Custom Input View

First, let's import the necessary header files and create an instance of the custom input view:

```markdown
// ViewController.m

#import <UIKit/UIKit.h>
#import "CustomKeyboard.h"

@interface ViewController : UIViewController

@property (nonatomic, strong) UITextField *myTextField;

@end

// ViewController.m

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // Create an instance of the custom input view
    CustomKeyboard *customKeyboard = [[CustomKeyboard alloc] initWithBundle:[NSBundle mainBundle]];

    // Set up the keyboard's input view
    self.myTextField.inputView = customKeyboard.customKeyboardView;

    // Bring the text field to the front and become first responder
    [self.myTextField becomeFirstResponder];
}