表单程序生成的布局为 XML 中的布局 android

Question

最近学习了android例子的代码，是录音的例子，有两个自定义的classes扩展按钮eg.RecordButton和PlayButton

代码如下：

public class AudioRecordTest extends Activity
{
    private static final String LOG_TAG = "AudioRecordTest";
    private static String mFileName = null;

    private RecordButton mRecordButton = null;
    private MediaRecorder mRecorder = null;

    private PlayButton   mPlayButton = null;
    private MediaPlayer   mPlayer = null;

    class RecordButton extends Button {
        boolean mStartRecording = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onRecord(mStartRecording);
                if (mStartRecording) {
                    setText("Stop recording");
                } else {
                    setText("Start recording");
                }
                mStartRecording = !mStartRecording;
            }
        };

        public RecordButton(Context ctx) {
            super(ctx);
            setText("Start recording");
            setOnClickListener(clicker);
        }
    }

    class PlayButton extends Button {
        boolean mStartPlaying = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onPlay(mStartPlaying);
                if (mStartPlaying) {
                    setText("Stop playing");
                } else {
                    setText("Start playing");
                }
                mStartPlaying = !mStartPlaying;
            }
        };

        public PlayButton(Context ctx) {
            super(ctx);
            setText("Start playing");
            setOnClickListener(clicker);
        }
    }



    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        LinearLayout ll = new LinearLayout(this);
        mRecordButton = new RecordButton(this);
        ll.addView(mRecordButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        mPlayButton = new PlayButton(this);
        ll.addView(mPlayButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        setContentView(ll);
    }


}

我想改成XML，但是return找不到class的错误

 Suppressed: java.lang.ClassNotFoundException: com.example.user.test.MainActivity.RecordButton

Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available

并且在XML设计器视图中，它还有一个

 java.lang.LinkageError (loader attempt a duplicate class definition for name : RecordButton)

这是我尝试构建的 XML：

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center"
    tools:context=".MainActivity">

    <com.example.user.test.MainActivity.RecordButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/rec_btn" />

    <com.example.user.test.MainActivity.PlayButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/play_btn" />

</LinearLayout>

有没有我遗漏的东西，我检查了包名是正确的。我该如何解决？

更新：清单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.user.test" >

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

Answer 1

首先，尝试 classical clean/rebuild 项目。它将确保您的代码确实存在问题，而不是调试器

然后，我建议你在不同的文件中声明你的两个 classes，它会更具可读性，而且使用内部 classes 时更容易出现问题。

我看到您的问题与此 post 中的问题有关：extend button android, xml layout，您是否尝试了给定的答案？

I understand "(included into another class)" as you have an inner class RecordButton.

Assuming your package is AudioRecordTest.test (which would be a very bad name choice) and your RecordButton class is an inner class of AudioRecord.class, you need to use:

BTW: any particular reason you create it as an inner class instead of having it separate?

您正在为按钮使用内部 class。那么你必须使用它的方式是不同的。使用之前的 post 或将您的 class 添加到不同的 java 文件中。

表单程序生成的布局为 XML 中的布局 android

Form program generated layout to XML layout in android

java

xml

android

xml-layout