<p class="input-group">
        <input type="text" readonly class="form-control" id="startTime"
               uib-datepicker-popup="yyyy-MM-dd" ng-model="st"
               is-open="startTimeBox.opened"
               datepicker-options="dateOptions"
               ng-required="false"
               show-button-bar="false"
               close-text="Close"/>
           <span class="input-group-btn">
                 <button type="button" class="btn btn-default" ng-click="startTimeOpen()"><i class="glyphicon glyphicon-calendar"></i></button>
           </span>
</p>

昨天还好好的，今天打开 就成这样了！

期望效果：