fix(picker): pass data and role to the dismiss based on button click or backdrop (#19787)

- Pass the button role on dismiss of the picker (on button click or backdrop tap)
- Pass the selected values in the data on dismiss ONLY if the dismiss role is not "cancel" or "backdrop"
- Call the cancel handler when dismissing if the role is "cancel" or "backdrop"

Fixes #18454

core/src/components/picker/picker.tsx

@@ -2,7 +2,7 @@ import { Component, ComponentInterface, Element, Event, EventEmitter, Host, Meth
 
 import { getIonMode } from '../../global/ionic-global';
 import { Animation, AnimationBuilder, CssClassMap, OverlayEventDetail, OverlayInterface, PickerButton, PickerColumn } from '../../interface';
-import { dismiss, eventMethod, prepareOverlay, present, safeCall } from '../../utils/overlays';
+import { BACKDROP, dismiss, eventMethod, isCancel, prepareOverlay, present, safeCall } from '../../utils/overlays';
 import { getClassMap } from '../../utils/theme';
 
 import { iosEnterAnimation } from './animations/ios.enter';
@@ -163,19 +163,29 @@ export class Picker implements ComponentInterface, OverlayInterface {
     return Promise.resolve(this.columns.find(column => column.name === name));
   }
 
-  private buttonClick(button: PickerButton) {
-    // if (this.disabled) {
-    //   return;
-    // }
-
-    // keep the time of the most recent button click
-    // a handler has been provided, execute it
-    // pass the handler the values from the inputs
-    const shouldDismiss = safeCall(button.handler, this.getSelected()) !== false;
-    if (shouldDismiss) {
-      return this.dismiss();
+  private async buttonClick(button: PickerButton) {
+    const role = button.role;
+    if (isCancel(role)) {
+      return this.dismiss(undefined, role);
     }
-    return Promise.resolve(false);
+    const shouldDismiss = await this.callButtonHandler(button);
+    if (shouldDismiss) {
+      return this.dismiss(this.getSelected(), button.role);
+    }
+    return Promise.resolve();
+  }
+
+  private async callButtonHandler(button: PickerButton | undefined) {
+    if (button) {
+      // a handler has been provided, execute it
+      // pass the handler the values from the inputs
+      const rtn = await safeCall(button.handler);
+      if (rtn === false) {
+        // if the return value of the handler is false then do not dismiss
+        return false;
+      }
+    }
+    return true;
   }
 
   private getSelected() {
@@ -194,11 +204,14 @@ export class Picker implements ComponentInterface, OverlayInterface {
   }
 
   private onBackdropTap = () => {
-    const cancelBtn = this.buttons.find(b => b.role === 'cancel');
-    if (cancelBtn) {
-      this.buttonClick(cancelBtn);
-    } else {
-      this.dismiss();
+    this.dismiss(undefined, BACKDROP);
+  }
+
+  private dispatchCancelHandler = (ev: CustomEvent) => {
+    const role = ev.detail.role;
+    if (isCancel(role)) {
+      const cancelButton = this.buttons.find(b => b.role === 'cancel');
+      this.callButtonHandler(cancelButton);
     }
   }
 
@@ -219,6 +232,7 @@ export class Picker implements ComponentInterface, OverlayInterface {
           zIndex: `${20000 + this.overlayIndex}`
         }}
         onIonBackdropTap={this.onBackdropTap}
+        onIonPickerWillDismiss={this.dispatchCancelHandler}
       >
         <ion-backdrop
           visible={this.showBackdrop}

core/src/components/picker/test/basic/index.html

@@ -48,6 +48,10 @@
       const pickerController = document.querySelector('ion-picker-controller');
       const pickerElement = await pickerController.create({
         buttons: [{
+          text: 'Cancel',
+          role: 'cancel',
+          handler: () => console.log('Clicked Cancel!')
+        }, {
           text: 'Save',
           handler: () => console.log('Clicked Save!')
         }, {
@@ -112,7 +116,12 @@
         }],
         cssClass: customClass
       });
-      return await pickerElement.present();
+
+      await pickerElement.present();
+
+      const { data, role } = await pickerElement.onDidDismiss();
+
+      console.log('Picker dismissed!', data, role);
     }
   </script>
 </body>