ios – 在NativeScript中执行XHR-Request时出现UICollectionView

the behavior of the UICollectionViewFlowLayout is not defined because:
the item height must be less than the height of the UICollectionView minus the section insets top and bottom values,minus the content insets top and bottom values.

The relevant UICollectionViewFlowLayout instance is <_UIAlertControllerCollectionViewFlowLayout: 0x7f99fe411ea0>,and it is attached to ; layer = ; contentOffset: {0,0}; contentSize: {0,0}> collection view layout: <_UIAlertControllerCollectionViewFlowLayout: 0x7f99fe411ea0>.
Make a symbolic breakpoint at UICollectionViewFlowLayoutBreakForInvalidSizes to catch this in the debugger.

我试图执行的代码：

打字稿：

makeRatingCall(userRating) {
    var score = userRating;
    var film_edition_id = "123456789";
    var computer_name = ConfigurationService.getUserData().user_username;
    var api_key = "key";
    return new Promise( function (resolve,reject) {
        let xhr = new XMLHttpRequest();
        xhr.open("POST","my-url" + this.formatParams({film_edition_id,score,computer_name,api_key }),true);
        xhr.setRequestHeader("Accept","application/json");
        xhr.onload = function() {
            if (xhr.readyState === 4 && xhr.status === 200) {
                resolve(JSON.parse(xhr.responseText).err_code);
            } else {
                reject(xhr.responseText);
            }
        }
        xhr.onerror = function( err ) {
            reject ( err );
        }
        xhr.send();
    });
}

formatParams = function ( params ){
    return "?" + Object.keys(params).map((key) => {
        return `${key}=${encodeURIComponent(params[key])}`
    }).join("&")
}

rateIt() {
    var translate = this.translateService;
    this.makeRatingCall( this.currentRating )
        .then(function ( err_code ) {
            if (err_code == 0) {
                dialogs.alert({
                    title: translate.instant("VOTE_SUCCESSFUL"),message: translate.instant("VOTE_SUCCESSFUL_MSG"),okButtonText: translate.instant("OK")
                });
                this.rateInteraction = false;
            } else if (err_code == 1) {
                dialogs.alert({
                    title: translate.instant("ALREADY_VOTED"),message: translate.instant("ALREADY_VOTED_MSG"),okButtonText: translate.instant("OK")
                });
            } else {
                dialogs.alert({
                    title: translate.instant("VOTE_FAILED"),message: translate.instant("VOTE_FAILED_MSG"),okButtonText: translate.instant("OK")
                });
            }
        } )
        .catch(function ( err ) {
            dialogs.alert({
                title: translate.instant("VOTE_FAILED"),okButtonText: translate.instant("OK")
            }); 

        });
}

HTML：

<GridLayout columns="*4,*,*" rows="*">
            <Button col="0" row="0" [text]="'SEND_RATING'|translate" class="send-rating-button" (onTap)="rateIt()"
            [isUserInteractionEnabled]="rateInteraction"></Button>
            <Image src="{{ user_rating_imageurls[0] }}" col="1" row="0" class="star-image" (onTap)="rateFromUser('1')"
                [isUserInteractionEnabled]="rateInteraction"></Image>
            <Image src="{{ user_rating_imageurls[1] }}" col="2" row="0" class="star-image" (onTap)="rateFromUser('2')"
                [isUserInteractionEnabled]="rateInteraction"></Image>
            <Image src="{{ user_rating_imageurls[2] }}" col="3" row="0" class="star-image" (onTap)="rateFromUser('3')"
                [isUserInteractionEnabled]="rateInteraction"></Image>
            <Image src="{{ user_rating_imageurls[3] }}" col="4" row="0" class="star-image" (onTap)="rateFromUser('4')"
                [isUserInteractionEnabled]="rateInteraction"></Image>
            <Image src="{{ user_rating_imageurls[4] }}" col="5" row="0" class="star-image" (onTap)="rateFromUser('5')"
                [isUserInteractionEnabled]="rateInteraction"></Image>
        </GridLayout>

CSS：

.send-rating-button {
    margin-top: 10;
    margin-left: 30;
    margin-right: 10;
    margin-bottom: 10;
    background-color: yellow;
}

.star-image {
    width: 30;
    margin: 10;
}

我不知道如何处理这个错误,有没有人给我一个暗示？ ：d