Angular - How to pass object dynamically to div element using [ngstyle]

Question

I'm trying to make grid-row and grid-column to be dynamically populated from API.

component.html

<div *ngFor = "let element of elements">
   <div [ngStyle]="styleObject(element.Row,element.Column)">{{element['Tool Name']}}</div>
</div>

component.ts

styleObject(row : String,Column:String): Object {
    let obj :Object;
    obj = {'grid-row':''+Number(row),'grid-column':''+Number(Column)};
    console.log(obj);
    return obj.toString;
}

This way in the console it is printing but it's not reflecting in UI. Console Image

It worked properly when I tried to populate the data manually as

<div [ngStyle]="{'grid-column':'9','grid-row':'9'}">{{element['Tool Name']}}</div>

In the Inspect Element mode, the attribute is showing as enter image description here

Where am I making mistake? Thanks in advance.

Answer 1

According to NgStyle docs,

Set a collection of style values using an expression that returns key-value pairs.

<some-element [ngStyle]="objExp">...</some-element>

You need to return styleObject as key-value pair type instead of string type.

styleObject(row : String, Column:String): Object {
  let obj :Object;
  obj = {'grid-row':''+Number(row),'grid-column':''+Number(Column)};
  return obj;
}

You may check out this sample demo.

---

Updated for grid layout issue

For your grid layout, should have .grid-container and .grid-item.

.grid-container

Wrap the whole div element and turn it to the grid.

.grid-item

The grid item with [ngStyle] have to place here so that it will be positioned based on grid-row and grid-column.

---

component.html

<div class="grid-container">
  <div *ngFor="let element of elements" class="grid-item" 
    [ngStyle]="styleObject(element.row, element.column)">
    {{element['name']}}
  </div>
</div>

.component.css

.grid-container {
  display: grid;
  grid-row-gap: 50px;
  grid-template-columns: auto auto auto;
  justify-content: center;
  background-color: #2196F3;
  padding: 10px;
}

.grid-item {
  background-color: rgba(255, 255, 255, 0.8);
  border: 1px solid rgba(0, 0, 0, 0.8);
  padding: 20px;
  font-size: 30px;
  text-align: center;
}

Sample Grid Layout on StackBlitz