小编sur*_*nde的帖子

在ionic中切换到另一段时图表消失，如何解决这个问题？我是离子的新手

当我打开这个页面时它显示正常图表但是当我改变段并返回时，图表变得不可见，请解决这个问题
这是我的HTML代码

<ion-header>
  <ion-navbar  color="darkblue">
    <ion-title class = "header">Lead</ion-title>
  </ion-navbar>

  <ion-toolbar no-border-top color="primary">
    <ion-segment [(ngModel)]="target" color="white">
        <ion-segment-button value="report">
            Report
        </ion-segment-button>
        <ion-segment-button value="graph">
            Graph
        </ion-segment-button>
    </ion-segment>
  </ion-toolbar>
</ion-header>

<ion-content>
    <div [ngSwitch]="target">

            <div *ngSwitchCase = "'report'" >
        <ion-card padding-top=10px>
          <ion-card-header>
              Bar Chart
          </ion-card-header>
                <ion-card-content>
                    <canvas #barCanvas></canvas>
                </ion-card-content>
        </ion-card>
            </div>


      <div *ngSwitchCase = "'graph'" >
        <ion-card padding-top=10px>
        <ion-card-header>Report</ion-card-header>
        <ion-card-content>

        </ion-card-content>
      </ion-card>
    </div>
  </div>
</ion-content>

这是我的打字稿代码

这是我的打字稿，我在其中实现了所有图表详细信息。

import { Component, ViewChild } from '@angular/core';
import { Chart } from 'chart.js';

@Component({
    templateUrl: 'mytarget.html' …

我正在尝试在对话框上添加回收站视图，但对话框未显示任何内容...我已在回收站视图上添加卡片，并想在对话框上显示回收站视图

android.support.v7.app.AlertDialog.Builder dialog = new android.support.v7.app.AlertDialog.Builder(getContext());
LayoutInflater inflater = (LayoutInflater)   getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View dialogView = inflater.inflate(R.layout.last_transaction_report, null);
recyclerView = (RecyclerView) dialogView.findViewById(R.id.transactio_rep_recyclerView);
dialog.setView(dialogView);

AlertDialog alertDialog = dialog.create();
// alertDialog.setContentView(dialogView);
alertDialog.show();

adapter = new TransactionReportCardAdapter(listTransactionDetails, this);
recyclerView.setAdapter(adapter);

错误:(29,44)错误:无法访问未找到com.google.android.gms.common.internal.safeparcel.AbstractSafeParcelable的AbstractSafeParcelable类文件

 public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
  private static final String TAG = MyFirebaseInstanceIDService.class.getSimpleName();

@Override
public void onTokenRefresh() {
    super.onTokenRefresh();
    String refreshedToken = FirebaseInstanceId.getInstance().getToken();

    // Saving reg id to shared preferences
    storeRegIdInPref(refreshedToken);

    // sending reg id to your server
    sendRegistrationToServer(refreshedToken);

    // Notify UI that registration has completed, so the progress indicator can be hidden.
    Intent registrationComplete = new Intent(Config.REGISTRATION_COMPLETE);
    registrationComplete.putExtra("token", refreshedToken);
    LocalBroadcastManager.getInstance(this).sendBroadcast(registrationComplete);
}

private void sendRegistrationToServer(final String token) {
    // sending gcm token to server
    Log.e(TAG, "sendRegistrationToServer: " + token); …

片段 MoneyTransferFragment 的代码......

MoneyTransferFragment moneyTransferFragment = new MoneyTransferFragment();
                    Bundle b = new Bundle();
                    b.putSerializable("UserValidateObject",userValidate);
                    b.putSerializable("BeneficiaryObject",beneficiaryDetails);
                    moneyTransferFragment.setArguments(b);

我想检索该对象的第二个片段的代码......

Bundle b = getArguments();
    userValidate =(UserValidate) b.getSerializable("UserValidateObject");
    Log.i("getuserValidate",userValidate.toString());

在日志中显示错误......

java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference