NG Block UI

A Block UI implementation for Angular

Installation

Add to your project via npm

npm install ng-block-ui --save

Include the BlockUIModule in your main app module.

// All other imports
import { BlockUIModule } from 'ng-block-ui';

@NgModule({
  imports: [
    BlockUIModule.forRoot()
  ],
  ...
})
export class AppModule { }

Quick Start

Wrap your main components in your app root template with a block-ui component.

Import the BlockUI decorator into your component and declare a property with the decorator. This decorator will auto wire this property to the main Block UI instance of your app.

To start blocking your app, simply invoke the start method. This method also can take a custom message to display while blocking. Once finished call the stop method to stop blocking the app.

import { Component } from '@angular/core';

// Import BlockUI decorator & optional NgBlockUI type
import { BlockUI, NgBlockUI } from 'ng-block-ui';

@Component({
  selector: 'app-root',
  template: `
    <block-ui>
      <!-- Your app markup here -->
    </block-ui>
  `
})
export class AppComponent {
  // Decorator wires up blockUI instance
  @BlockUI() blockUI: NgBlockUI;

  constructor() {
    this.blockUI.start('Loading...'); // Start blocking

    setTimeout(() => {
      this.blockUI.stop(); // Stop blocking
    }, 2000);
  }

Current Release

For more information and/or migrating to the newest version see Releases.

Settings

Settings can be changed on the module level and component/directive level. Also, in some cases settings can be overwritten via the method level.

Default Message

A default message can be configured to be shown instead of passing a message each time to the start method. The default message will be shown any time blocking is activated.

Setting	Type	Description
message	string	Custom message to be displayed while blocking.

Module Level

@NgModule({
  imports: [
    BlockUIModule.forRoot({
      message: 'Default Message'
    })
  ],
  ...
})
export class AppModule { }

Component Level

<block-ui message="Default Message">
  <!-- Markup here -->
</block-ui>

Method Level

@Component({
  ...,
  template: `
    <block-ui message="Default Message">
      <!-- Your markup here -->
    </block-ui>
  `
})
export class Cmp {
  @BlockUI() blockUI: NgBlockUI;

  defaultMessage() {
    this.blockUI.start(); // "Default Message" will display
  }

  customMessage() {
    this.blockUI.start('Updating...'); // "Updating..." will display
  }
}

Delay Start/Stop

When blocking with fast service calls the block overlay can flicker for a small amount of time. To prevent this a delayStart and a delayStop can be configured to prevent this scenario.

Setting	Type	Description
delayStart	number	Waits given amount of milliseconds before starting to block.
delayStop	number	Waits given amount of milliseconds before stopping current block.

Module Level

@NgModule({
  imports: [
    BlockUIModule.forRoot({
      delayStart: 500,
      delayStop: 500
    })
  ],
  ...
})
export class AppModule { }

Component Level

<block-ui [delayStart]="500" [delayStop]="500">
  <!-- Your app markup here -->
</block-ui>

Custom Template

If you want to display other markup than the default spinner and message then you can provide a custom template. Custom templates can be provided as a Component or TemplateRef. The template will then be used instead of the default template whenever blocking.

Setting	Type	Description
template	Component | TemplateRef	Custom template to be used when blocking

Component Custom Template

Create a component and declare it in your app module. The component also will need to be added to the entryComponents property of the module.

Example Component:

Note: When providing a Component as a template just add the {{message}} interpolation to your template and it will display your default message or the message passed to the start method.

// Template component
// Use block-ui-template class to center div if desired
@Component({
  template: `
    <div class="block-ui-template">
      <img src="logo.png" />
      <p>{{ message }}</p>
    </div>
  `,
})
export class BlockTemplateCmp {}

Module Level

@NgModule({
  imports: [
    BlockUIModule.forRoot({
      template: BlockTemplateCmp
    })
  ],
  declarations: [
    ...,
    BlockTemplateCmp // Declare template component
  ],
  entryComponents: [ BlockTemplateCmp ]
})
export class AppModule { }

Component Level

@Component({
  selector: "app-root",
  template: `
    <block-ui [template]="blockTemplate">
      <!-- Your markup here -->
    </block-ui>
  `,
})
export class AppComponent {
  // Declare template component
  blockTemplate: BlockTemplateCmp = BlockTemplateCmp;
}

TemplateRef Custom Template

Add a <ng-template> with a template reference variable to the view. Then pass the template reference variable to the blockUI component using the [template] property.

Note: TemplateRef templates can only be set on a Component level.

Component Level

@Component({
  selector: "cmp",
  template: `
    <ng-template #blockTemplate>
      <div class="block-ui-template">
        <img src="logo.png" />
      </div>
    </ng-template>

    <block-ui [template]="blockTemplate">
      <!-- Your app markup here -->
    </block-ui>
  `,
})
export class Cmp {}

Block UI Directive

Sometimes you want to only apply blocking to a certain element in your app. The Block UI directive can be added to an element to apply blocking only to that specific element.

Add the *blockUI structural directive to any element and pass it an instance name *blockUI="'contact-list'".

Then in a component create a class property using the Block UI decorator with the instance name @BlockUI('contact-list'). This will then take care of wiring up that property to point to that specific instance in your app.

@Component({
  selector: 'app-cmp',
  template: `
    <div>
      <div *blockUI="'contact-list'">
        <!-- List markup -->
      </div>
    </div>
  `
})
export class AppComponent {
  // Pass instance name to decorator
  @BlockUI('contact-list') blockUIList: NgBlockUI;

  constructor() {
    this.blockUIList.start('Loading...'); // Start blocking element only
    this.blockUIList.stop(); // Stop blocking
  }

Directive Settings

Angular has a specific syntax for passing properties to structural directives. Properties are passed in key: value; pair. To pass settings to a Block UI directive they must be passed as shown below.

<div
  *blockUI="'instance-name'; message: 'Loading'; template: blockTemplate"
></div>

NgBlockUI Instance

NgBlockUI Instance Properties

Below highlights all the properties that can be found on a BlockUI instance when a class property is decorated with the @BlockUI() decorator.

Property	Description
name	Name of the targeted instance (defaults to main instance).
isActive	Indicates if the targeted instance is blocking.
start	Starts blocking for instance, can be passed an optional message.
stop	Stops blocking for instance.
reset	Stops blocking for all targeted instances regardless of the delayStop option.
resetGlobal	Stops blocking app wide for all instances regardless of the delayStop option.
update	Updates current instances blocking message with the passed message.
unsubscribe	Unsubscribe an instance so it no longer can be blocked. All BlockUI components/directives unsubscribe by default during onDestroy.

NgBlockUI Instance Settings

Below are all the settings that can be passed as a second argument to the @BlockUI() decorator (@BlockUI(<name>, <settings>)).

Property	Description
scopeToInstance	When set to true a unique name will be given to the blockUI instance which will "scope" it to the parent component instance.

BlockUIService

In some cases you may want to have more control over all the instances in you app. Instead of declaring separate instances with the @BlockUI() decorator you can use the BlockUIService. This service allows you to easily target multiple instance across your app.

Method	Parameters	Description
isActive	target: string | string[]	Indicates if the targeted instance(s) is blocking.
start	target: string | string[], message?: any	Starts blocking for a single instance or multiple instances by passing instance name(s).
stop	target: string | string[]	Stops blocking for a single instance or multiple instances by passing instance name(s).
update	target: string | string[], message: any	Updates message for a single instance or multiple instances by passing instance name(s).
reset	target: string | string[]	Resets blocking for a single instance or multiple instances by passing instance name(s).
resetGlobal	N/A	Resets blocking app wide for all instances.
unsubscribe	target: string | string[]	Unsubscribes a single instance or multiple instances by passing instance name(s).

Other Modules

Http Module - Automatically block during http requests

Router Module - Prevent route changes while blocking

Guides

SystemJS Config

Examples

BlockUI Component - Stackblitz

BlockUI Component Default Message - Stackblitz

BlockUI Directive - Stackblitz

BlockUI Custom Spinner Styles - Stackblitz

BlockUI Custom Template - Stackblitz