codenameone - 使用验证器验证表单

Question

在验证器组件上，我需要评估哪个文本字段出错，我找到了 Isvalid() 方法，但对我的海豚无效，因为我不知道哪个值出错。

我如何知道哪个约束和组件无效？,

boolean isValid(Component cmp) 

不公开。

问候

Answer 1

我不确定您是否使用了正确的Validator，因为您没有提供代码。但是，下面的代码应该可以帮助您入门:

使用单个验证器进行验证:

import com.codename1.ui.validation.LengthConstraint;
import com.codename1.ui.validation.RegexConstraint;
import com.codename1.ui.validation.Validator;

.
.
.

Validator val = new Validator();
val.setValidationFailureHighlightMode(Validator.HighlightMode.UIID);
val.addConstraint(emailField, RegexConstraint.validEmail())
   .addConstraint(passwordField, new LengthConstraint(6));

if (val.isValid()) {
    System.out.println("All validated fields pass the constraints");
} else {
    // show dialog here
}

使用单独的验证器进行验证:

import com.codename1.ui.validation.LengthConstraint;
import com.codename1.ui.validation.RegexConstraint;
import com.codename1.ui.validation.Validator;

.
.
.

Validator valEmail = new Validator();
valEmail.setValidationFailureHighlightMode(Validator.HighlightMode.UIID);
valEmail.addConstraint(emailField, RegexConstraint.validEmail());
if (valEmail.isValid()) {
    System.out.println("Email field passes the constraint");
} else {
    // show dialog here
}

Validator valPassword = new Validator();
valPassword.setValidationFailureHighlightMode(Validator.HighlightMode.UIID);
valPassword.addConstraint(passwordField, new LengthConstraint(6));

if (valPassword.isValid()) {
    System.out.println("Password field passes the constraint");
} else {
    // show dialog here
}

除了上述内容之外，我建议使用 TextComponent，因为它将在每个组件下方无缝显示错误消息，而不需要对话框。

作为奖励，您甚至可以禁用提交按钮，直到所有经过验证的字段都有效:

import com.codename1.ui.validation.LengthConstraint;
import com.codename1.ui.validation.RegexConstraint;
import com.codename1.ui.validation.Validator;
import com.codename1.ui.*;

.
.
.

TextComponent email = new TextComponent().constraint(TextArea.EMAILADDR)
        .labelAndHint("Email").focusAnimation(false);
email.setName("email");

TextComponent password = new TextComponentPassword()
        .labelAndHint("Password").focusAnimation(false);
password.setName("password");

Button submit = new Button("Submit");

Validator val = new Validator();
val.setValidationFailureHighlightMode(Validator.HighlightMode.UIID);
val.addSubmitButtons(submit)
        .addConstraint(email, RegexConstraint.validEmail())
        .addConstraint(password, new LengthConstraint(6));