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我是Android新手,并试图自己学习.但我正在与Fragments度过艰难时期.我正在创建一个简单的应用程序来学习片段.我觉得这看起来很傻但我真的无法让它发挥作用.

我想要做的只是点击Fragment_One中的按钮(buttonSayHi),Fragment_One应该被Fragment_Two取代.

我不确定何时调用Fragment代码以及我应该在哪里编写代码来调用第二个片段.我收到错误:无法启动Activity组件.

但是,如果我丢弃按钮的监听器并且片段显示在活动中,则代码可以正常工作.

我做了大量的研究,阅读developer.android.com上的片段教程以及Lars Vogella的教程.我认为我的概念并不清楚.

任何帮助将不胜感激.

以下是代码:

activity_main.xml中

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/frameLayoutFragmentContainer"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

</FrameLayout>

fragment_one.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <EditText
        android:id="@+id/editTextPersonName"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName" >

        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/buttonSayHi"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Say Hi" 
        android:onClick="onButtonClicked"/>

</LinearLayout>

fragment_two.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/textViewResult"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="I will say Hi!" />

</LinearLayout>

MainActivity.java

package com.example.fragmenttutorial;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import …

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@Override
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仅当我点击“图表”区域时，才会显示该图表。我用谷歌搜索，但是找不到解决方案。以下是代码：

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        YAxis …