如何使用图标向UITextField添加填充

Question

I currently have the following code to setup a password textfield:

  self.passwordTextField = [UITextField new];
  self.passwordTextField.placeholder = @"Password";
  self.passwordTextField.font = [UIFont systemFontOfSize:18.f];
  self.passwordTextField.secureTextEntry = YES;
  self.passwordTextField.returnKeyType = UIReturnKeyDone;
  self.passwordTextField.delegate = self;
  self.passwordTextField.backgroundColor = [UIColor colorWithRed:255 green:255 blue:255 alpha:0.64];
  self.passwordTextField.layer.borderColor = [[UIColor lightGrayColor] CGColor];
  self.passwordTextField.layer.borderWidth = 1.0f;

  CGFloat textFieldHeight = 45.f;
  CGFloat textFieldWidth = 300.f;
  self.passwordTextField.frame = CGRectMake(DIALOG_VIEW_WIDTH/2.f - textFieldWidth / 2.f, 240.f, textFieldWidth, textFieldHeight);

  UIImageView *icon = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"text-input-icon-password-key.png"]];
  icon.frame = CGRectMake(0, 0, 45.f, 45.f);
  icon.backgroundColor = [UIColor lightGrayColor];
  self.passwordTextField.leftView = icon;
  self.passwordTextField.leftViewMode = UITextFieldViewModeAlways;

  [self.dialogView addSubview:self.passwordTextField];

which gives me this:

However, I want to add some more transparent padding to the left of the placeholder text and to the right of the image view showing the icon. Any ideas how this can be done?

---

Update: Thanks for the replies. I achieved this in the end by creating a UIView for the entire object with a UIImageView for the icon and a UITextField embedded in another UIView for the text. The result was as follows:

Answer 1

" Update: Thanks for the replies. I achieved this in the end by creating a UIView for the entire object with a UIImageView for the icon and a UITextField embedded in another UIView for the text. "

You could have continued using the leftView property of the UITextField such:

UIView *vwContainer = [[UIView alloc] init];
[vwContainer setFrame:CGRectMake(0.0f, 0.0f, 50.0f, 45.0f)];
[vwContainer setBackgroundColor:[UIColor clearColor]];

UIImageView *icon = [[UIImageView alloc] init];
[icon setImage:[UIImage imageNamed:@"text-input-icon-password-key.png"]];
[icon setFrame:CGRectMake(0.0f, 0.0f, 45.0f, 45.0f)];
[icon setBackgroundColor:[UIColor lightGrayColor]];

[vwContainer addSubview:icon];

[self.passwordTextField setLeftView:vwContainer];
[self.passwordTextField setLeftViewMode:UITextFieldViewModeAlways];

Answer 2

If you want full control over the custom layout then you should subclass UITextField and override both the leftViewRectForBounds: and placeholderRectForBounds: methods. Then you can return the frames for both areas and thus specify the padding in between them.

Answer 3

Here is a UITextField subclass that allows for insets on the leftView (icon), the text and the placeholder text. These are all configurable in IB

class UITextFieldWithInsets: UITextField {
    @IBInspectable var horizontalInset:CGFloat = 0
    @IBInspectable var verticalInset:CGFloat = 0

    @IBInspectable var leftViewHorizontalInset:CGFloat = 0
    @IBInspectable var leftViewVerticalInset:CGFloat = 0

    override func textRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , horizontalInset , verticalInset)
    }

    override func editingRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds , horizontalInset + leftViewHorizontalInset + leftViewWidth, verticalInset)
    }

    override func placeholderRectForBounds(bounds: CGRect) -> CGRect {
        return CGRectInset(bounds, horizontalInset + leftViewHorizontalInset + leftViewWidth, verticalInset)
    }

    override func leftViewRectForBounds(bounds: CGRect) -> CGRect {
        let verticalInsetForCentered = (bounds.height - leftViewHeight) / 2
        return CGRect(x: leftViewHorizontalInset, y: leftViewVerticalInset > 0 ? leftViewVerticalInset : verticalInsetForCentered, width: leftViewWidth, height: leftViewHeight)
    }

    private var leftViewWidth : CGFloat { get { return leftView?.frame.width ?? 0 } }
    private var leftViewHeight : CGFloat { get { return leftView?.frame.width ?? 0 } }
}

Answer 4

您可以使用更宽的图像作为带有右透明列的图标。