AngularJS conditional required

Question

I want to validate a form if an input text has value, or another one, or both of them.

For example

<!-- if username has data -->
<div class="username">
        <label for="username">Username:</label>
        <input type="text" id="username" name="username" required
               minlength="4" maxlength="8"
               placeholder="4 to 8 characters long" />
    </div>

<!-- if nickname has data -->
<div class="nickname">
        <label for="nickname">Nickname:</label>
        <input type="text" id="nickname" name="nickname" required
               minlength="4" maxlength="8"
               placeholder="4 to 8 characters long" />
    </div>

<!-- or if both has data submit is enabled -->
<input type="submit" value="Submit">

-- EDIT --

Ok now I have something weird, it seems that the "&&" operator doesn't work in HTML, so I'm a bit stuck..

Actually, with your help, my button can be clicked if the condition is verified. But strangely : - Button is not disabled - If the condition is not verified, my button doesn't display my ng-if message.

HTML

<form class="form-horizontal" role="form" name="myForm" novalidate>
    <div class="card-body card-padding">
        <div class="form-group">
            <div class="container-fluid">
                <div class="row">
                    <label class="col-sm-2 control-label">Firstname</label>
                    <div class="col-sm-8">
                        <tags-input ng-model="myForm.firstname"
                                    min-length="0"
                                    name="firstname"
                                    use-strings="true" class="form-control" required>
                        </tags-input>
                    </div>
                </div>
            </div>
        </div>
        <div class="form-group">
            <div class="container-fluid">
                <div class="row">
                    <label class="col-sm-2 control-label">Name</label>
                    <div class="col-sm-8">
                        <tags-input ng-model="myForm.name"
                                    min-length="0"
                                    name="name"
                                    use-strings="true" class="form-control" required>
                        </tags-input>
                    </div>
                </div>
            </div>
        </div>
        <div class="form-group">
            <div class="container-fluid">
                <div class="row">
                    <label class="col-sm-2 control-label">Email</label>
                    <div class="col-sm-8">
                        <tags-input ng-model="myForm.email"
                                    min-length="0"
                                    name="email"
                                    use-strings="true" class="form-control" required>
                        </tags-input>
                    </div>
                </div>
            </div>
        </div>
        <div class="form-group">
            <div class="container-fluid">
                <div class="row">
                    <label class="col-sm-2 control-label">Username</label>
                    <div class="col-sm-8">
                        <tags-input ng-model="myForm.username"
                                    min-length="0"
                                    name="username"
                                    use-strings="true" class="form-control" required>
                        </tags-input>
                    </div>
                </div>
            </div>
        </div>
        <div class="form-group">
            <div class="container-fluid">
                <div class="row">
                    <label class="col-sm-2 control-label">Nickname</label>
                    <div class="col-sm-8">
                        <tags-input ng-model="myForm.nickname"
                                    min-length="0"
                                    name="nickname"
                                    use-strings="true" class="form-control" required>
                        </tags-input>
                    </div>
                </div>
            </div>
        </div>
        <div class="form-group" data-ng-show="btnOk">
            <div class="col-sm-offset-2 col-sm-10">
                <button type="button" data-ng-click="action()" class="btn btn-success btn-sm"
                        ng-disabled="(!myForm.username.$valid || !myForm.nickname.$valid) && !myForm.email.$valid && !myForm.name.$valid && !myForm.firstname.$valid">
                    <span ng-if="(!myForm.username.$valid || !myForm.nickname.$valid) && !myForm.email.$valid && !myForm.name.$valid && !myForm.firstname.$valid">Some required fields are missing</span>
                    <span ng-if="(myForm.username.$valid || myForm.nickname.$valid) && myForm.email.$valid && myForm.name.$valid && myForm.firstname.$valid">{{button}}</span>
                </button>
            </div>
        </div>
    </div>
</form>

How can I bypass this behavior ?

Answer 1

Resolved this by adding bool in my condition like:

<div class="col-sm-offset-2 col-sm-10">
                            <button type="button" data-ng-click="action()" class="btn btn-success btn-sm"
                                    ng-disabled="(myForm.firstname.$valid == false || myForm.name.$valid == false || myForm.email.$valid == false || (myForm.username.$valid == false && myForm.nickname.$valid == false))">
                                <span ng-if="(myForm.firstname.$valid == false || myForm.name.$valid == false || myForm.email.$valid == false || (myForm.username.$valid == false && myForm.nickname.$valid == false))">Some required fields are missing</span>
                                <span ng-if="(myForm.firstname.$valid && myForm.name.$valid && myForm.email.$valid && (myForm.username.$valid || myForm.nickname.$valid))">{{button}}</span>
                            </button>
                        </div>