feat(inputs) debounce input and change events (#13764)

* feat(helpers) add debounce helper

* feat(searchbar) debounce ionInput

* feat(range) debounce ionChange

* feat(input) debouce ionInput

* feat(textarea) debounce ionInput

* feat(range) make debounceChange private

* feat(searchbar) make debounceInput private

* feat(inputs) change default debounce to 0 in input/textarea

packages/core/src/components.d.ts

@@ -1155,6 +1155,7 @@ declare global {
       checked?: boolean;
       clearInput?: boolean;
       clearOnEdit?: boolean;
+      debounce?: number;
       disabled?: boolean;
       inputmode?: string;
       max?: string;
@@ -2880,6 +2881,7 @@ declare global {
       autofocus?: boolean;
       clearOnEdit?: boolean;
       cols?: number;
+      debounce?: number;
       disabled?: boolean;
       maxlength?: number;
       minlength?: number;

packages/core/src/components/input/input.tsx

@@ -1,5 +1,6 @@
 import { Component, Element, Event, EventEmitter, Prop, PropDidChange } from '@stencil/core';
 
+import { debounce } from '../../utils/helpers';
 import { createThemedClasses } from '../../utils/theme';
 import { InputComponent } from './input-base';
 
@@ -23,6 +24,11 @@ export class Input implements InputComponent {
 
   @Element() private el: HTMLElement;
 
+  /**
+   * @output {Event} Emitted when the input value has changed.
+   */
+  @Event() ionInput: EventEmitter;
+
   /**
    * @output {Event} Emitted when the styles change.
    */
@@ -83,6 +89,18 @@ export class Input implements InputComponent {
    */
   @Prop({ mutable: true }) clearOnEdit: boolean;
 
+  /**
+   * @input {number} Set the amount of time, in milliseconds, to wait to trigger the `ionInput` event after each keystroke. Default `0`.
+   */
+  @Prop() debounce: number = 0;
+  @PropDidChange('debounce')
+  private debounceInput() {
+    this.ionInput.emit = debounce(
+      this.ionInput.emit.bind(this.ionInput),
+      this.debounce
+    );
+  }
+
   /**
    * @input {boolean} If true, the user cannot interact with the input. Defaults to `false`.
    */
@@ -192,6 +210,7 @@ export class Input implements InputComponent {
 
 
   componentDidLoad() {
+    this.debounceInput();
     this.emitStyle();
 
     // By default, password inputs clear after focus when they have content
@@ -225,6 +244,7 @@ export class Input implements InputComponent {
 
   inputChanged(ev: any) {
     this.value = ev.target && ev.target.value;
+    this.ionInput.emit(ev);
     this.emitStyle();
   }
 
@@ -242,15 +262,15 @@ export class Input implements InputComponent {
     }
   }
 
-  inputKeydown() {
+  inputKeydown(ev: any) {
-    this.checkClearOnEdit();
+    this.checkClearOnEdit(ev);
   }
 
 
   /**
   * Check if we need to clear the text input if clearOnEdit is enabled
   */
-  checkClearOnEdit() {
+  checkClearOnEdit(ev: any) {
     if (!this.clearOnEdit) {
       return;
     }
@@ -258,15 +278,16 @@ export class Input implements InputComponent {
     // Did the input value change after it was blurred and edited?
     if (this.didBlurAfterEdit && this.hasValue()) {
       // Clear the input
-      this.clearTextInput();
+      this.clearTextInput(ev);
     }
 
     // Reset the flag
     this.didBlurAfterEdit = false;
   }
 
-  clearTextInput() {
+  clearTextInput(ev: any) {
     this.value = '';
+    this.ionInput.emit(ev);
   }
 
   hasFocus(): boolean {

packages/core/src/components/input/readme.md

@@ -47,6 +47,11 @@ boolean
 boolean
 
 
+#### debounce
+
+number
+
+
 #### disabled
 
 boolean
@@ -179,6 +184,11 @@ boolean
 boolean
 
 
+#### debounce
+
+number
+
+
 #### disabled
 
 boolean
@@ -277,6 +287,9 @@ string
 #### ionFocus
 
 
+#### ionInput
+
+
 #### ionStyle
 
 

packages/core/src/components/range/range.tsx

@@ -1,6 +1,6 @@
 import { Component, Element, Event, EventEmitter, Listen, Method, Prop, PropDidChange, State } from '@stencil/core';
 import { BaseInputComponent, GestureDetail } from '../../index';
-import { clamp } from '../../utils/helpers';
+import { clamp, debounce } from '../../utils/helpers';
 
 @Component({
   tag: 'ion-range',
@@ -75,6 +75,13 @@ export class Range implements BaseInputComponent {
    * `ionChange` event after each change in the range value. Default `0`.
    */
   @Prop() debounce: number = 0;
+  @PropDidChange('debounce')
+  private debounceChange() {
+    this.ionChange.emit = debounce(
+      this.ionChange.emit.bind(this.ionChange),
+      this.debounce
+    );
+  }
 
   /*
    * @input {boolean} If true, the user cannot interact with the range. Default false.
@@ -126,13 +133,14 @@ export class Range implements BaseInputComponent {
 
   @PropDidChange('value')
   protected valueChanged(val: boolean) {
-    setTimeout(() => this.ionChange.emit({value: val}), this.debounce);
+    this.ionChange.emit({value: val});
     this.emitStyle();
   }
 
   componentWillLoad() {
     this.inputUpdated();
     this.createTicks();
+    this.debounceChange();
     this.emitStyle();
   }
 

packages/core/src/components/searchbar/searchbar.tsx

@@ -1,4 +1,5 @@
-import { Component, Element, Event, EventEmitter, Prop, State } from '@stencil/core';
+import { Component, Element, Event, EventEmitter, Prop, PropDidChange, State } from '@stencil/core';
+import { debounce } from '../../utils/helpers';
 
 
 @Component({
@@ -86,6 +87,13 @@ export class Searchbar {
    * @input {number} Set the amount of time, in milliseconds, to wait to trigger the `ionInput` event after each keystroke. Default `250`.
    */
   @Prop({ mutable: true }) debounce: number = 250;
+  @PropDidChange('debounce')
+  private debounceInput() {
+    this.ionInput.emit = debounce(
+      this.ionInput.emit.bind(this.ionInput),
+      this.debounce
+    );
+  }
 
   /**
    * @input {string} Set the input's placeholder. Default `"Search"`.
@@ -115,6 +123,7 @@ export class Searchbar {
 
   componentDidLoad() {
     this.positionElements();
+    this.debounceInput();
   }
 
   /**
@@ -153,9 +162,7 @@ export class Searchbar {
    */
   inputChanged(ev: any) {
     this.value = ev.target.value;
-    setTimeout(() => {
     this.ionInput.emit(ev);
-    }, this.debounce);
   }
 
   inputUpdated() {

packages/core/src/components/textarea/readme.md

@@ -66,6 +66,11 @@ boolean
 number
 
 
+#### debounce
+
+number
+
+
 #### disabled
 
 boolean
@@ -148,6 +153,11 @@ boolean
 number
 
 
+#### debounce
+
+number
+
+
 #### disabled
 
 boolean
@@ -211,6 +221,9 @@ string
 #### ionFocus
 
 
+#### ionInput
+
+
 #### ionStyle
 
 

packages/core/src/components/textarea/textarea.tsx

@@ -1,5 +1,6 @@
 import { Component, Element, Event, EventEmitter, Prop, PropDidChange } from '@stencil/core';
 
+import { debounce } from '../../utils/helpers';
 import { createThemedClasses } from '../../utils/theme';
 import { TextareaComponent } from '../input/input-base';
 
@@ -29,6 +30,11 @@ export class Textarea implements TextareaComponent {
 
   @Element() private el: HTMLElement;
 
+  /**
+   * @output {Event} Emitted when the input value has changed.
+   */
+  @Event() ionInput: EventEmitter;
+
   /**
    * @output {Event} Emitted when the styles change.
    */
@@ -64,6 +70,18 @@ export class Textarea implements TextareaComponent {
    */
   @Prop({ mutable: true }) clearOnEdit: boolean;
 
+  /**
+   * @input {number} Set the amount of time, in milliseconds, to wait to trigger the `ionInput` event after each keystroke. Default `0`.
+   */
+  @Prop() debounce: number = 0;
+  @PropDidChange('debounce')
+  private debounceInput() {
+    this.ionInput.emit = debounce(
+      this.ionInput.emit.bind(this.ionInput),
+      this.debounce
+    );
+  }
+
   /**
    * @input {boolean} If true, the user cannot interact with the textarea. Defaults to `false`.
    */
@@ -141,6 +159,7 @@ export class Textarea implements TextareaComponent {
   }
 
   componentDidLoad() {
+    this.debounceInput();
     this.emitStyle();
   }
 
@@ -160,8 +179,9 @@ export class Textarea implements TextareaComponent {
     });
   }
 
-  clearTextInput() {
+  clearTextInput(ev: any) {
     this.value = '';
+    this.ionInput.emit(ev);
   }
 
   inputBlurred(ev: any) {
@@ -173,6 +193,7 @@ export class Textarea implements TextareaComponent {
 
   inputChanged(ev: any) {
     this.value = ev.target && ev.target.value;
+    this.ionInput.emit(ev);
     this.emitStyle();
   }
 
@@ -183,14 +204,14 @@ export class Textarea implements TextareaComponent {
     this.emitStyle();
   }
 
-  inputKeydown() {
+  inputKeydown(ev: any) {
-    this.checkClearOnEdit();
+    this.checkClearOnEdit(ev);
   }
 
   /**
   * Check if we need to clear the text input if clearOnEdit is enabled
   */
-  checkClearOnEdit() {
+  checkClearOnEdit(ev: any) {
     if (!this.clearOnEdit) {
       return;
     }
@@ -198,7 +219,7 @@ export class Textarea implements TextareaComponent {
     // Did the input value change after it was blurred and edited?
     if (this.didBlurAfterEdit && this.hasValue()) {
       // Clear the input
-      this.clearTextInput();
+      this.clearTextInput(ev);
     }
 
     // Reset the flag

packages/core/src/utils/helpers.ts

@@ -295,3 +295,11 @@ export function domControllerAsync(domControllerFunction: Function, callback?: F
     });
   });
 }
+
+export function debounce(func: Function, wait: number = 250) {
+  let timer: number;
+  return (...args: any[]): void => {
+    clearTimeout(timer);
+    timer = setTimeout(func, wait, ...args);
+  };
+}