Web Components Grid State Persistence
The Ignite UI for Web Components State Persistence in Web Components Grid allows developers to easily save and restore the grid state. When the IgcGridState
is applied on the Web Components IgcGridComponent
, it exposes the GetState
, GetStateAsString
, ApplyState
and ApplyStateFromString
methods that developers can use to achieve state persistence in any scenario.
Supported Features
IgcGridState
directive supports saving and restoring the state of the following features:
- Sorting
- Filtering
- Advanced Filtering
- Paging
- CellSelection
- RowSelection
- ColumnSelection
- RowPinning
- Expansion
- GroupBy
- Columns
- Multi column headers
- Columns order
- Column properties defined by the
IColumnState
interface.
Usage
The getState
method returns the grid state in a IgcGridStateInfo
object, containing all the state info. Additional steps may be required in order to save it.
The GetStateAsString
returns a serialized JSON string, so developers can just take it and save it on any data storage (database, cloud, browser localStorage, etc).
The developer may choose to get only the state for a certain feature/features, by passing in an array with feature names as an argument. Empty array will result to using the default state options.
<igc-grid id="grid">
<igc-grid-state id="gridState"></igc-grid-state>
</igc-grid>
var gridState = document.getElementById('gridState') as IgcGridStateComponent;
// get an `IgcGridStateInfo` object, containing all features original state objects, as returned by the grid public API
const state: IgcGridStateInfo = gridState.getState();
// get all features` state in a serialized JSON string
const stateString: string = gridState.getStateAsString();
// get the sorting and filtering expressions
const sortingFilteringStates: IgcGridStateInfo = gridState.getState(['sorting', 'filtering']);
ApplyState
- The method accepts a IgcGridStateInfo
object as argument and will restore the state of each feature found in the object or specified features as second argument.
ApplyStateFromString
- The method accepts a serialized JSON string as argument and will restore the state of each feature found in the JSON string or specified features as second argument.
gridState.applyState(gridState);
gridState.applyStateFromString(gridStateString);
gridState.applyState(sortingFilteringStates)
The Options
object implements the IgcGridStateOptions
interface, i.e. for every key, which is the name of a certain feature, there is the boolean value indicating if this feature state will be tracked. GetState
/GetStateAsString
methods will not put the state of these features in the returned value and ApplyState
/ApplyStateFromString
methods will not restore state for them.
gridState.options = { cellSelection: false, sorting: false };
The simple to use single-point API's allows to achieve a full state persistence functionality in just a few lines of code. Copy paste the code from below - it will save the grid state in the browser LocalStorage
object every time the user leaves the current page. Whenever the user returns to main page, the grid state will be restored. No more need to configure those complex advanced filtering and sorting expressions every time to get the data you want - do it once and have the code from below do the rest for your users:
constructor() {
window.addEventListener("load", () => { this.restoreGridState(); });
window.addEventListener("beforeunload", () => { this.saveGridState(); });
}
// Using methods that work with IgcGridStateInfo object.
public saveGridState() {
const state = this.gridState.getState();
window.localStorage.setItem('grid-state', JSON.stringify(state));
}
public restoreGridState() {
const state = window.localStorage.getItem('grid-state');
if (state) {
this.gridState.applyState(JSON.parse(state));
}
}
// Or using string alternative methods.
public saveGridStateString() {
const state = this.gridState.getStateAsString();
window.localStorage.setItem('grid-state', state);
}
public restoreGridStateString() {
const state = window.localStorage.getItem('grid-state');
if (state) {
this.gridState.applyStateFromString(state);
}
}
Demo
Limitations
getStateAsString
method uses JSON.stringify() method to convert the original objects to a JSON string. JSON.stringify() does not support Functions, thats why theIgcGridState
component will ignore the columnsformatter
,filters
,summaries
,sortStrategy
,cellClasses
,cellStyles
,headerTemplate
andbodyTemplate
properties.