模拟微信讨论组的头像集合

vm.picUrl = [];
var items = [‘pic1‘, ‘pic2‘, ‘pic3‘, ‘pic4‘, ‘pic5‘, ......]; //1-9 and more
angular.forEach(items, function(item) {
    vm.picUrl.push(item.url);// 图片的url
});

<div mult-picture pictures="picUrl" pic-height="200" pic-width="200"></div>
<div mult-picture pictures="picUrl" pic-height="50" pic-width="50"></div>

.mult-pic-background {
  background-color: #e2e2e2;
}

.mult-pic-flex {
  display: flex;
}

.mult-pic-justify-content {
  justify-content: center;
}

.mult-pic-box-align {
  align-items: center;
}

//最多显示9个
define([‘angular‘, ‘bootstrap‘], function(angular) {
  return angular.registerDirective(‘micromallMultPicture‘, [
    function() {
      return {
        replace: true,
        restrict: ‘EA‘,
        scope: {
          pictures: "=",
          picHeight: "=",
          picWidth: "="
        },
        transclude: true,
        template: ‘<div ng-switch = "pictures.length">
                    <div ng-switch-when = "1" class="mult-pic-background" ng-style="{width : picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[0] |qiniu : imgHeight}}"/>
                    </div>
                    <div ng-switch-when = "2" class="mult-pic-background mult-pic-flex" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                      <div class="mult-pic-flex mult-pic-box-align">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-when = "3" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                      <div class="mult-pic-flex mult-pic-justify-content">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight, \‘margin-left\‘: 0}"
                        ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[2] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-when = "4" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                        <img ng-repeat="pic in pictures track by $index" class="pull-left" ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pic |qiniu: imgHeight/rowNum}}"/>
                    </div>
                    <div ng-switch-when = "5" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘, padding: marginCol}">
                      <div class="mult-pic-flex mult-pic-justify-content">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[2] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[3] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[4] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-when = "6" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘, padding: marginCol}">
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[2] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[3] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[4] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[5] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-when = "7" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                      <div class="mult-pic-flex mult-pic-justify-content">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight, \‘margin-left\‘: 0}"
                        ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[2] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[3] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[4] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[5] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[6] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-when = "8" class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                      <div class="mult-pic-flex mult-pic-justify-content">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[0] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[1] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pictures[2] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[3] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[4] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                      <div class="mult-pic-flex">
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[5] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[6] |qiniu: imgHeight/rowNum}}"/>
                        <img ng-style="{margin: imgPadding, width: smallwidth, height: smallHeight}" ng-src="{{pictures[7] |qiniu: imgHeight/rowNum}}"/>
                      </div>
                    </div>
                    <div ng-switch-default class="mult-pic-background" ng-style="{width: picWidth + \‘px\‘, height: picHeight + \‘px\‘}">
                        <img ng-repeat="pic in pictures track by $index" class="pull-left" ng-style="{margin : imgPadding, width: smallwidth, height: smallHeight}"
                        ng-src="{{pic |qiniu: imgHeight/rowNum}}" ng-if="$index < 9"/>
                    </div>
                  </div>‘,
        link: function(scope, element, attrs) {
          scope.$watch(‘pictures‘, function() {
            var colNum, imgPadding, isMoreRow, rowNum, smallHeight, _ref, _ref1;
            //求根,大约分几行
            rowNum = Math.floor(Math.sqrt((_ref = scope.pictures) != null ? _ref.length : void 0));
            isMoreRow = true;
            //根据行数求列数
            colNum = Math.ceil(((_ref1 = scope.pictures) != null ? _ref1.length : void 0) / rowNum);
            //5, 求行数约为2, 列数约为3, 则行数为2; 7, 求行数约为2, 求列数为4, 则行数为3
            if (colNum - rowNum <= 1) {
              isMoreRow = false;
              scope.rowNum = colNum;
            } else (colNum - rowNum > 1) {
              scope.rowNum = rowNum + 1;
            }
            //最多显示9个
            if (scope.rowNum >= 3) {
              scope.rowNum = 3;
            }

            imgPadding = scope.picHeight / 25;
            scope.imgPadding = imgPadding + ‘px 0 0 ‘ + imgPadding + ‘px‘;
            //一行图片间隔两块, 两行图片间隔3块, 剩于展示的高度为
            scope.imgHeight = scope.picHeight - imgPadding * (scope.rowNum + 1);

            //除以行数, 每行多高, 正方形, 所以每行多宽
            smallHeight = scope.imgHeight / scope.rowNum;
            scope.smallHeight = scope.smallwidth = smallHeight + ‘px‘;

            // 类似于数字5, 明明应用3*3, 却显示2行, 需要加一个剩余高度一办的margin
            if (!isMoreRow) {
              scope.marginCol = (scope.picHeight - rowNum * (smallHeight + imgPadding)) / 2 - imgPadding / 2 + ‘px 0‘;
            }
          });
        }
      };
    }
  ]);
});