angular.js ng-repeat for creating grid

Question

I'm trying to create a grid using bootstrap 3 and angularjs.

The grid I'm trying to create is this, repeated using ng-repeat.

<div class="row">
 <div class="col-md-4">item</div>
 <div class="col-md-4">item</div>
 <div class="col-md-4">item</div>
</div>

I've tried using ng-if with ($index % 3 == 0) to add the rows, but this doesn't seem to be working right. Any suggestions would be great!

Thank you!

EDIT: Here's the code I ended up going with that worked:

<div ng-repeat="item in items">
  <div ng-class="row|($index % 3 == 0)">
    <ng-include class="col-sm-4" src="'views/items/item'"></ng-include> 
  </div>
</div>

Answer 1

The accepted answer is the obvious solution however presentation logic should remain in view and not in controllers or models. Also I wasn't able to get the OP's solution to work.

Here are two ways to do create grid system when you have a flat list(array) of items. Say our item list is a alphabet:

Plunker here

$scope.alphabet = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 
                   'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'];

Method 1:

This is a pure angular solution.

<div class="row" ng-repeat="letter in alphabet track by $index" ng-if="$index % 4 == 0">
  <div class="col-xs-3 letter-box" 
       ng-repeat="i in [$index, $index + 1, $index + 2, $index + 3]" 
       ng-if="alphabet[i] != null">
    <div>Letter {{i + 1}} is: <b> {{alphabet[i]}}</b></div>
  </div>
</div>

The outer loop execute after every 4 iterations and creates a row. For each run of the outer loop the inner loop iterates 4 times and creates columns. Since the inner loop runs 4 times regardless of whether we have elements in array or not, the ng-if makes sure that no extraneous cols are created if the array ends before inner loop completes.

Method 2:

This is much simpler solution but requires angular-filter library.

<div class="row" ng-repeat="letters in alphabet | chunkBy:4">
  <div class="col-xs-3 letter-box" ng-repeat="letter in letters" >
    <div>Letter {{$index + 1}} is: <b> {{letter}}</b></div>
  </div>
</div>

The outer loop creates groups of 4 letters, corresponding to our 'row'

[['A', 'B', 'C', 'D'], ['E', 'F', 'G', 'H'], ... ]

The inner loop iterates over the group and creates columns.

Note: Method 2 might require evaluation of filter for each iteration of outer loop, hence method 2 may not scale very well for huge data sets.

Answer 2

This is an old answer!

I was still a bit new on Angular when I wrote this. There is a much better answer below from Shivam that I suggest you use instead. It keeps presentation logic out of your controller, which is a very good thing.

Original answer

You can always split the list you are repeating over into a list of lists (with three items each) in your controller. So you list is:

$scope.split_items = [['item1', 'item2', 'item3'], ['item4', 'item5', 'item6']];

And then repeat it as:

<div ng-repeat="items in split_items" class="row">
    <div ng-repeat="item in items" class="col-md-4">
        item
    </div>
</div>

Not sure if there is a better way. I have also tried playing around with ng-if and ng-switch but I could never get it to work.

Answer 3

You can simply chunk your array into subarrays of N inside of your controller. Sample code:

var array = ['A','B','C','D','E','F','G','H'];

var chunk = function(arr, size) {
   var newArr = [];
      for (var i=0; i<arr.length; i+=size) {
          newArr.push(arr.slice(i, i+size));
      }
   return newArr;
};

$scope.array = chunk(array, 2);

Now in *.html file You simply ng-repeat through the array

<div class="row" ng-repeat="chunk in array">
    <div class="col-md-6" ng-repeat="item in chunk">
         {{item}}
    </div>
</div>

That workout for me :) Good luck!

Answer 4

One might say that the below solution does not follow the grid rules of having row divs, but another solution would be to drop the row class ( or use it outside of the ng-repeat) and use the clearfix class instead:

<div class="col-md-12">
  <div ng-repeat="item in items">
    <div ng-class="{'clearfix': $index%3 === 0}"></div>
    <div class="col-md-4">{{item}}</div>
  </div>
</div>

As far as I can see, this looks almost the same as with row class, but please comment on possible flaws (except the one I mentioned above).

Answer 5

Using ng-repeat-start and ng-repeat-end

<div class="row">
    <div ng-repeat-start="item in items track by $index" class="col-sm-4">
      {{item}}
    </div>
    <div ng-repeat-end ng-if="($index+1) % 3 == 0" class="clearfix"></div>
</div>

Easy to adapt for different media query using .visible-* classes

<div class="row">
    <div ng-repeat-start="item in items track by $index" class="col-lg-2 col-md-4 col-sm-6">
      {{item}}
    </div>
    <div ng-repeat-end>
        <div class="clearfix visible-lg-block" ng-if="($index+1) % 6 == 0"></div>
        <div class="clearfix visible-md-block" ng-if="($index+1) % 3 == 0"></div>
        <div class="clearfix visible-sm-block" ng-if="($index+1) % 2 == 0"></div>
    </div>
</div> 

I find clear and concise to have row management logic outside of the main repeat block. Separation of concerns :-)

Answer 6

A bit late answer but i used this and i belive it is better for some cases. You can use Angular Filter package and its ChunkBy filter for this. Although this package would be a heavy lifting for this single task, there is other useful filters in it for different tasks. The code i used is like this:

<div class="row mar-t2" ng-repeat="items in posts | chunkBy:3">
    <div class="col-md-4" ng-repeat="post in items">
        <img ng-src="{{post.featured_url}}" class="img-responsive" />
        <a ng-click="modalPop(post.id)"><h1 class="s04-bas2">{{post.title.rendered}}</h1></a>
        <div class="s04-spotbox2" ng-bind-html="post.excerpt.rendered"></div>
    </div>
</div>

Answer 7

I took a slightly different method using ngInit. I'm not sure if this is the appropriate solution since the ngInit documentation states

The only appropriate use of ngInit is for aliasing special properties of ngRepeat, as seen in the demo below. Besides this case, you should use controllers rather than ngInit to initialize values on a scope.

I'm not really sure if this falls under that case, but I wanted to move this functionality away from the controller to give the template designer easier freedom to group by rows with bootstrap. I still haven't tested this for binding, but seeing as i'm tracking by $index I don't think that should be a problem.

Would love to hear feedback.

I created a filter called "splitrow" that takes one argument (the count of how many items in each row)

.filter('splitrow', function(){
    return function (input, count){
        var out = [];
            if(typeof input === "object"){
                for (var i=0, j=input.length; i < j; i+=count) {
                    out.push(input.slice(i, i+count));
                }
            }
        return out;
    }
});

Within the view template I organized the bootstrap rows as follows:

<div ng-init="rows = (items|splitrow:3)">
    <div ng-repeat='row in rows' class="row">
        <div ng-repeat="item in row track by $index" class="col-md-4">
            {{item.property}}
        </div>
    </div>
</div>

I edited @Shivam's Plunker to use this method. It requires no external libraries.

Plunker

Answer 8

My solution is very similar to @CodeExpress one. I made a batch filter that groups items of an array (the name is borrowed it from Twig's counterpart filter). I don't handle associative arrays for simplicity's sake.

angular.module('myapp.filters', [])
    .filter('batch', function() {
        var cacheInputs = [];
        var cacheResults = [];

        return function(input, size) {
            var index = cacheInputs.indexOf(input);

            if (index !== -1) {
                return cacheResults[index];
            }

            var result = [];

            for (i = 0; i < input.length; i += size) {
                result.push(input.slice(i, i + size));
            }

            cacheInputs.push(input);
            cacheResults.push(result);

            return result;
        }
    })
;

It can be used this way:

<div ng-repeat="itemsRow in items|batch:3">
    <div class="row">
        <div ng-repeat="item in itemsRow">
            <div class="col-md-4">
                ...
            </div>
        </div>
    </div>
</div>

The filter results are cached to avoid the 10 $digest() iterations reached. Aborting! error.

Answer 9

An Angular2 version of @CodeExpress's pure angular solution.

alphabet: string[] = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 
                   'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'];

<div *ngIf='alphabet && alphabet.length'>
    <div *ngFor='#letter of alphabet; #i = index' >
        <div class="row" *ngIf='i % 4 == 0'>
            <div class="col-md-3" *ngFor='#n of [i,i+1,i+2,i+3]'>
                {{alphabet[n]}}
            </div>
        </div>
    </div>
</div>

Answer 10

This should work

<div ng-repeat="item in items">
    <div ng-class="{row : ($index % 3 == 0)}">
        ... 
    </div>
</div>

Answer 11

Update for Angular9:

<div class="container-fluid" *ngFor="let item of alphabet; let index = index">
  <div class="row" *ngIf="index % 4 == 0">
    <div *ngFor="let i of [index, index+1, index+2, index+3]">
      <div class="col-xs-3">{{alphabet[i]}}</div>
    </div>
  </div>
</div>