Question

以下Android代码应修改“Hello World！”语句今天说“今天是8月7日”，并在一年中的任何其他日子说“错误”。但是，我得到的只是“Hello World！”奇怪的是，我在完全新的程序上以完全相同的方式运行代码，但没有在类FirstFragment中嵌套类CheckDate。我试图通过删除FirstFragment类来解决这个问题，但是这导致了我的MainActivity类中的错误，我用它为应用程序创建了侧边栏应用程序。我可以做些什么来保持侧边栏，并让应用程序修改文本“Hello World！”它应该说什么？

FIRST FRAGMENT

if (wbPart.WorkbookStylesPart.Stylesheet.NumberingFormats != null) {

First Fragment $ CheckDate.xml

package com.example.gcsd.gcsdapp;

import android.app.Fragment;
import android.icu.util.Calendar;
import android.icu.util.GregorianCalendar;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.app.FragmentManager;
import android.widget.TextView;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;
import android.icu.util.GregorianCalendar;
import android.icu.util.Calendar;

public class FirstFragment extends Fragment {

View myView;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup 
container, Bundle savedInstanceState) {
myView = inflater.inflate(R.layout.home, container, false);
return myView;

}

public class CheckDate extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    TextView textView = (TextView) findViewById(R.id.textView);

    GregorianCalendar cal = new GregorianCalendar();

    System.out.println(cal.get(Calendar.DATE)); //prints 4
    System.out.println(cal.get(Calendar.MONTH) + 1); //this starts at 0, not 1. Therefore, add 1
    System.out.println(cal.get(Calendar.YEAR)); //2017

    if ((cal.get(Calendar.DAY_OF_MONTH) + 0 == 4) && (cal.get(Calendar.MONTH) + 1 == 8)) { //Is it the fourth of the month of 2017?
        System.out.println("TODAY IS AUGUST FOURTH");
        textView.setText("TODAY IS AUGUST FOURTH");
    } else {
        System.out.println("ERROR");
        textView.setText("ERROR");
    }

}
}
}

主要活动

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.gcsd.gcsdapp.FirstFragment$CheckDate">

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textView"
android:text="Hello World!"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />

</RelativeLayout>

Answer 1

用以下代码替换您的First Fragment类

package com.example.gcsd.gcsdapp;

    import android.app.Fragment;
    import android.icu.util.Calendar;
    import android.icu.util.GregorianCalendar;
    import android.os.Bundle;
    import android.support.annotation.Nullable;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.support.v4.app.FragmentManager;
    import android.widget.TextView;
    import android.os.Bundle;
    import android.widget.TextView;
    import android.icu.util.GregorianCalendar;
    import android.icu.util.Calendar;

    public class FirstFragment extends Fragment {

    View myView;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup 
    container, Bundle savedInstanceState) {
    myView = inflater.inflate(R.layout.checkdate, container, false);

        TextView textView = (TextView) myView.findViewById(R.id.textView);

        GregorianCalendar cal = new GregorianCalendar();

        System.out.println(cal.get(Calendar.DATE)); //prints 4
        System.out.println(cal.get(Calendar.MONTH) + 1); //this starts at 0, not 1. Therefore, add 1
        System.out.println(cal.get(Calendar.YEAR)); //2017

        if ((cal.get(Calendar.DAY_OF_MONTH) + 0 == 4) && (cal.get(Calendar.MONTH) + 1 == 8)) { //Is it the fourth of the month of 2017?
            System.out.println("TODAY IS AUGUST FOURTH");
            textView.setText("TODAY IS AUGUST FOURTH");
        } else {
            System.out.println("ERROR");
            textView.setText("ERROR");
        }
    return myView;

    }
  }

我的应用程序不会修改嵌套在另一个类中的文本吗？

1 个答案: