我想在設備沒有攝像頭時提醒Ionic2警報。ionic 2警報在網頁上無法使用
當我啓動:離子服務
然後我嘗試以顯示信息如下:
let alert = Alert.create({
title: 'Camera not found',
subTitle: 'It seems your camera is not working on your device',
buttons: ['Ok']
});
this.nav.present(alert);
我有一個JavaScript錯誤
Uncaught EXCEPTION: Error during evaluation of "click"
ORIGINAL EXCEPTION: TypeError: rootNav.getActive is not a function
ORIGINAL STACKTRACE:
TypeError: rootNav.getActive is not a function
at Tab.NavController.present (http://localhost:8100/build/js/app.bundle.js:46996:36)
at SmartScan.takePicture (http://localhost:8100/build/js/app.bundle.js:60864:23)
at AbstractChangeDetector.ChangeDetector_SmartScan_0.handleEventInternal (eval at <anonymous> (http://localhost:8100/build/js/app.bundle.js:14578:17), <anonymous>:185:36)
at AbstractChangeDetector.handleEvent (http://localhost:8100/build/js/app.bundle.js:13892:25)
at AppView.dispatchEvent (http://localhost:8100/build/js/app.bundle.js:18772:46)
at AppView.dispatchRenderEvent (http://localhost:8100/build/js/app.bundle.js:18766:22)
at DefaultRenderView.dispatchRenderEvent (http://localhost:8100/build/js/app.bundle.js:33592:39)
at eventDispatcher (http://localhost:8100/build/js/app.bundle.js:33258:22)
at http://localhost:8100/build/js/app.bundle.js:33329:40
不管這個代碼在移動工作建立..?請詳細說明 –