我正在尝试通过点击事件添加动态标签。但是会收到一个错误，指出该功能无法识别。在嵌套容器中，我有一个问题，我无法通过getViewById找到特定的引用。只得到未发现的。我是否正确使用了getviewbyid？对于普通容器，引用不会出现问题。只有当这些嵌套在一起时，才有问题。 这是一个在哪里工作的链接。 Tap
<page xmlns="http://schemas.nativescript.org/tns.xsd" class="page" loaded="pageLoaded"
xmlns:dd="nativescript-drop-down"
xmlns:sd="nativescript-ui-sidedrawer"
xmlns:customControls="shared">
<ActionBar>
<label style="color:grey;" text="ZorrasBistro" class="mka actionlabel"/>
<Android>
<NavigationButton tap="onBackButtonTap" android.systemIcon="ic_menu_back" />
<label text="" tap="{{newItem}}" class="fas" horizontalAlignment="right" style="margin-right:30em;"/>
</Android>
<iOS>
<ActionItem id="exampleMenuButton" ios.position="right" automationText="ExampleMenu">
<ActionItem.actionView>
<label text="" class="fas"/>
</ActionItem.actionView>
</ActionItem>
</iOS>
</ActionBar>
<sd:RadSideDrawer id="sideDrawer">
<sd:RadSideDrawer.drawerContent>
<customControls:sidedrawer/>
</sd:RadSideDrawer.drawerContent>
<sd:RadSideDrawer.mainContent id="main">
<GridLayout id="example-background" loaded="onBackgroundLoaded">
<GridLayout id="form-content" class="form-content" rows="auto,*,auto" loaded="onContentLoaded">
<StackLayout class="top-border" row="0"/>
<ScrollView row="1" class="fields-section">
<StackLayout>
<!-- Bestellungname -->
<GridLayout ios:columns="auto,*" android:rows="auto,auto" verticalAlignment="top">
<Label text="BestellungName" class="field-title" />
<TextField id="ordername" text="{{ Ordername }}" class="field" ios:col="1" android:row="1" tap="onTextInputTapped" />
</GridLayout>
<StackLayout class="line"/>
<!-- Name -->
<GridLayout ios:columns="auto,*" android:rows="auto,auto" verticalAlignment="top">
<Label text="Optional" class="field-title" />
<TextField id="email" text="{{ email }}" class="field" ios:col="1" android:row="1" tap="onTextInputTapped" />
</GridLayout>
<StackLayout class="line"/>
<!-- Weiteres -->
<GridLayout ios:columns="auto,*" android:rows="auto,auto" verticalAlignment="top">
<Label text="Trinken" class="field-title" />
<TextField id="password" text="{{ password }}" class="field" ios:col="1" android:row="1" tap="onTextInputTapped" />
</GridLayout>
<StackLayout class="line"/>
<!-- ListPicker -->
<GridLayout android:rows="auto,auto" ios:columns="auto,*" verticalAlignment="top">
<StackLayout android:row="0" ios:col="0" orientation="horizontal">
<label text="Trinken" class="field-title" />
<label text="Anzahl" style="margin-left:100em;" class = "field-title"/>
</StackLayout>
<StackLayout android:row="1" ios:col="0" orientation="horizontal">
<ListPicker class="ListPicker" items="{{items}}" textField ="name" valueField="role" selectedIndex ="{{index}}" valueField ="id" selectedValue="{{theid}}">
</ListPicker>
<ListPicker class="ListPicker" items="{{items}}" textField="id" valueField="role" />
</StackLayout>
</GridLayout>
<GridLayout android:rows="auto,auto" ios:columns="auto,*" verticalAlignment="top">
<StackLayout id="labeldyn" android:row="0" ios:columns="auto,*" verticalAlignment="top">
</StackLayout>
<StackLayout id="listpickerdyn" android:row="0" ios:columns="auto,*" verticalAlignment="top">
</StackLayout>
</GridLayout>
<GridLayout android:rows="auto,auto" ios:columns="auto,*" verticalAlignment = "top">
<StackLayout row = "0" orientation="horizontal">
<label text="Mittagessen" class="field-title" />
<label text="Anzahl" style="margin-left:75em;" class="field-title"/>
</StackLayout>
<StackLayout row="1" orientation="horizontal">
<ListPicker class="ListPicker" items="{{Menu}}" textField="Menu" valueField="role"/>
<ListPicker class="ListPicker" items="{{Anzahl}}" valueField="role" />
</StackLayout>
</GridLayout>
<GridLayout android:rows="auto,auto" ios:columns="auto,*" verticalAlignment = "top">
<StackLayout row="0" orientation="horizontal">
<label text="Mittagessen" class="field-title"/>
<label text="Anzahl" style="margin-left:75em;" class="field-title"/>
</StackLayout>
<StackLayout row ="1" orientation="horizontal">
<ListPicker class="ListPicker" items="{{Menu}}" textField="Menu" valueField="role"/>
<ListPicker class="ListPicker" items="{{Anzahl}}" valueField="role" />
</StackLayout>
</GridLayout>
</StackLayout>
</ScrollView>
<Button text="Bestellen" class= "btn btn-active btn-rounded-lg" tap="neueBestell" row="2" />
</GridLayout>
<!-- Picture -->
<Image id="image" src="~/res/food.png" class="profile-picture" tap="onProfilePictureTapped"/>
</GridLayout>
</sd:RadSideDrawer.mainContent>
</sd:RadSideDrawer>
</page>
ViewModel.newItem = (args) => {
const page = args.object;
var label = page.getViewById("labeldyn");
var _label = new Label();
_label.Text = "Test";
console.log("Test Ausgabe:" + _label.Text);
label.addChild(_label);
};
TypeError: Cannot read property 'addChild' of undefined
File: "file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/gestures/gestures.js, line: 228, column: 40
StackTrace:
Frame: function:'ViewModel.newItem', file:'file:///data/data/org.nativescript.preview/files/app/newBestellung/newBestellung-view.js', line: 33, column: 15
Frame: function:'_executeCallback', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/gestures/gestures.js', line: 282, column: 27
Frame: function:'TapAndDoubleTapGestureListenerImpl.onSingleTapUp', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/gestures/gestures.js', line: 25, column: 17
Frame: function:'GesturesObserver.androidOnTouchEvent', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/gestures/gestures.js', line: 228, column: 41
Frame: function:'', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/core/view/view.js', line: 259, column: 25
Frame: function:'View.handleGestureTouch', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/core/view/view.js', line: 258, column: 18
Frame: function:'TouchListenerImpl.onTouch', file:'file:///data/data/org.nativescript.preview/files/app/tns_modules/tns-core-modules/ui/core/view/view.js', line: 33, column: 19
at com.tns.Runtime.callJSMethodNative(Native Method)
at com.tns.Runtime.dispatchCallJSMethodNative(Runtime.java:1203)
at com.tns.Runtime.callJSMethodImpl(Runtime.java:1083)
at com.tns.Runtime.callJSMethod(Runtime.java:1070)
at com.tns.Runtime.callJSMethod(Runtime.java:1050)
at com.tns.Runtime.callJSMethod(Runtime.java:1042)
at com.tns.gen.java.lang.Object_view_24_32_TouchListenerImpl.onTouch(Object_view_24_32_TouchListenerImpl.java:19)
at android.view.View.dispatchTouchEvent(View.java:12625)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3172)
at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2857)
at com.android.internal.policy.DecorView.superDispatchTouchEvent(DecorView.java:615)
at com.android.internal.policy.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1879)
at android.app.Activity.dispatchTouchEvent(Activity.java:3441)
at android.support.v7.view.WindowCallbackWrapper.dispatchTouchEvent(WindowCallbackWrapper.java:69)
at com.android.internal.policy.DecorView.dispatchTouchEvent(DecorView.java:577)
at android.view.View.dispatchPointerEvent(View.java:12877)
at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:5787)
at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:5582)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:5075)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:5128)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:5094)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:5231)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:5102)
at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:5288)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:5075)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:5128)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:5094)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:5102)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:5075)
at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:7887)
at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:7827)
at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:7788)
at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:7998)
at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:198)
at android.view.InputEventReceiver.nativeConsumeBatchedInputEvents(Native Method)
at android.view.InputEventReceiver.consumeBatchedInputEvents(InputEventReceiver.java:187)
at android.view.ViewRootImpl.doConsumeBatchedInput(ViewRootImpl.java:7961)
at android.view.ViewRootImpl$ConsumeBatchedInputRunnable.run(ViewRootImpl.java:8025)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:911)
at android.view.Choreographer.doCallbacks(Choreographer.java:723)
at android.view.Choreographer.doFrame(Choreographer.java:652)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:897)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:7000)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:441)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1408)
答案 0 :(得分：0)
尝试
const page = args.object.page;
代替
const page = args.object;
args.object将是标签本身而不是页面。