feat(view): expose method for android back override (NativeScript#5537)

MartoYankov · web-flow · commit cf8dcfa40cd6 · 2018-03-14T18:15:05.000+02:00
Expose method on View class onBackPressed(). Third party controls
like RadSideDrawer can use this method to override the default Android
back button handling. By default the app closes.
diff --git a/tns-core-modules/ui/core/view/view-common.ts b/tns-core-modules/ui/core/view/view-common.ts
@@ -203,7 +203,7 @@ export abstract class ViewCommon extends ViewBase implements ViewDefinition {
         return false;
     }
 
-    public _onBackPressed(): boolean {
+    public onBackPressed(): boolean {
         return false;
     }
 
diff --git a/tns-core-modules/ui/core/view/view.android.ts b/tns-core-modules/ui/core/view/view.android.ts
@@ -115,7 +115,7 @@ function initializeDialogFragment() {
             };
             view.notify(args);
 
-            if (!args.cancel && !view._onBackPressed()) {
+            if (!args.cancel && !view.onBackPressed()) {
                 super.onBackPressed();
             }
         }
diff --git a/tns-core-modules/ui/core/view/view.d.ts b/tns-core-modules/ui/core/view/view.d.ts
@@ -678,10 +678,11 @@ export abstract class View extends ViewBase {
      * @private
      */
     _onLivesync(): boolean;
+
     /**
-     * @private
+     * Derived classes can override this method to handle Android back button press. 
      */
-    _onBackPressed(): boolean;
+    onBackPressed(): boolean;
     /**
      * @private
      */
diff --git a/tns-core-modules/ui/frame/frame.android.ts b/tns-core-modules/ui/frame/frame.android.ts
@@ -249,7 +249,7 @@ export class Frame extends FrameBase {
         }
     }
 
-    public _onBackPressed(): boolean {
+    public onBackPressed(): boolean {
         if (this.canGoBack()) {
             this.goBack();
             return true;
@@ -884,7 +884,7 @@ class ActivityCallbacksImplementation implements AndroidActivityCallbacks {
             };
             view.notify(viewArgs);
 
-            if (!viewArgs.cancel && !view._onBackPressed()) {
+            if (!viewArgs.cancel && !view.onBackPressed()) {
                 callSuper = true;
             }
         }
diff --git a/tns-core-modules/ui/tab-view/tab-view.android.ts b/tns-core-modules/ui/tab-view/tab-view.android.ts
@@ -510,10 +510,10 @@ export class TabView extends TabViewBase {
         super.disposeNativeView();
     }
 
-    public _onBackPressed(): boolean {
+    public onBackPressed(): boolean {
         const currentView = this._selectedView;
         if (currentView) {
-            return currentView._onBackPressed();
+            return currentView.onBackPressed();
         }
 
         return false;

Original file line number	Diff line number	Diff line change
`@@ -203,7 +203,7 @@ export abstract class ViewCommon extends ViewBase implements ViewDefinition {`
`203`	`203`	`return false;`
`204`	`204`	`}`
`205`	`205`
`206`		`- public _onBackPressed(): boolean {`
	`206`	`+ public onBackPressed(): boolean {`
`207`	`207`	`return false;`
`208`	`208`	`}`
`209`	`209`
Original file line number	Diff line number	Diff line change
`@@ -115,7 +115,7 @@ function initializeDialogFragment() {`
`115`	`115`	`};`
`116`	`116`	`view.notify(args);`
`117`	`117`
`118`		`- if (!args.cancel && !view._onBackPressed()) {`
	`118`	`+ if (!args.cancel && !view.onBackPressed()) {`
`119`	`119`	`super.onBackPressed();`
`120`	`120`	`}`
`121`	`121`	`}`
Original file line number	Diff line number	Diff line change
`@@ -249,7 +249,7 @@ export class Frame extends FrameBase {`
`249`	`249`	`}`
`250`	`250`	`}`
`251`	`251`
`252`		`- public _onBackPressed(): boolean {`
	`252`	`+ public onBackPressed(): boolean {`
`253`	`253`	`if (this.canGoBack()) {`
`254`	`254`	`this.goBack();`
`255`	`255`	`return true;`
`@@ -884,7 +884,7 @@ class ActivityCallbacksImplementation implements AndroidActivityCallbacks {`
`884`	`884`	`};`
`885`	`885`	`view.notify(viewArgs);`
`886`	`886`
`887`		`- if (!viewArgs.cancel && !view._onBackPressed()) {`
	`887`	`+ if (!viewArgs.cancel && !view.onBackPressed()) {`
`888`	`888`	`callSuper = true;`
`889`	`889`	`}`
`890`	`890`	`}`
Original file line number	Diff line number	Diff line change
`@@ -510,10 +510,10 @@ export class TabView extends TabViewBase {`
`510`	`510`	`super.disposeNativeView();`
`511`	`511`	`}`
`512`	`512`
`513`		`- public _onBackPressed(): boolean {`
	`513`	`+ public onBackPressed(): boolean {`
`514`	`514`	`const currentView = this._selectedView;`
`515`	`515`	`if (currentView) {`
`516`		`- return currentView._onBackPressed();`
	`516`	`+ return currentView.onBackPressed();`
`517`	`517`	`}`
`518`	`518`
`519`	`519`	`return false;`