布局中的SurfaceView

Question

所以我已经做了很多搜索,但似乎无法找到我的SurfaceView无法显示的确切原因.这里有一些关于我正在做的事情的背景:

我有一个水平设置的线性布局.它包含一个ImageView,然后是一个垂直的线性布局,最后是另一个ImageView.在垂直线性布局中,有三件事:顶部的另一个ImageView,一个扩展的SurfaceView(称为MagnetView)和一个下面的ImageView.

这是xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal" >

 <!-- Left Magnetrak -->

 <ImageView
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:src="@drawable/vectorparts_01"
    android:adjustViewBounds="true" />

<!-- Middle Linear Layout -->        
<LinearLayout 
    android:layout_width="0dip"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:layout_weight="1">

    <!-- Top Bar with Lifes and Score counter -->
    <RelativeLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true">

    <ImageView
    android:adjustViewBounds="true"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:src="@drawable/vectorparts_22"/>

    <!-- Score counter -->
    <TextView
    android:id="@+id/myImageViewText"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentRight="true"
    android:layout_marginRight="10dp"
    android:layout_marginTop="5dp"
    android:gravity="center"
    android:text="000000000000"
    android:textColor="#000000" />

    <!-- Life1 -->
     <ImageView
        android:id = "@+id/life1"
        android:adjustViewBounds="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/vectorparts_13" 
        android:layout_alignParentLeft="true"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="1dp"
        android:gravity="center" />

     <!-- Life2 -->
     <ImageView
        android:id = "@+id/life2"
        android:adjustViewBounds="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/vectorparts_13" 
        android:layout_toRightOf="@id/life1"
        android:layout_marginTop="1dp"
        android:layout_marginLeft="1dp"
        android:gravity="center" />

     <!-- Life3 -->
     <ImageView
        android:id = "@+id/life3"
        android:adjustViewBounds="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/vectorparts_13" 
        android:layout_toRightOf="@id/life2"
        android:layout_marginTop="1dp"
        android:layout_marginLeft="1dp"
        android:gravity="center" />

    </RelativeLayout>

    <!-- SurfaceView -->
    <LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:id="@+id/middlesurface">

    </LinearLayout>

     <!-- Bottom Bar -->   
    <RelativeLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true"> 

    <ImageView
    android:adjustViewBounds="true"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:src="@drawable/vectorparts_02"/>


    </RelativeLayout>


</LinearLayout>

<!-- Right Magnetrak -->
   <ImageView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:src="@drawable/vectorparts_01"
android:adjustViewBounds="true" />

基本上,我希望MagnetView显示(或打孔)我把它放在布局中.但它没有显示.事实上,SurfaceView显示的唯一时间是我将活动的setContentView()显式设置为SurfaceView,取消其他所有内容.

这是实际的活动:

public class Magnetraks extends Activity {

MagnetView midSurf;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    midSurf = new MagnetView(this);
    LinearLayout midLL = new LinearLayout(this);

    midLL.findViewById(R.id.middlesurface);
    midLL.addView(midSurf);

    setContentView(R.layout.main);

    //Debugging purposes: run to see if middleSurface view is showing up when on its own.
    //setContentView(midSurf);


}

@Override
protected void onResume() {
 // TODO Auto-generated method stub
 super.onResume();
 midSurf.resume();
}

@Override
protected void onPause() {
 // TODO Auto-generated method stub
 super.onPause();
 midSurf.pause();
}

我应该将SurfaceView放在布局xml的顶部吗？我必须设置更多属性吗？我可以将SurfaceView叠加在其他所有内容上,使其半透明并绘制我需要的内容吗？任何帮助将不胜感激,因为我似乎无法掌握SurfaceViews的工作原理.它似乎是我的View层次结构的一部分,但随后文档告诉我它们完全不同.

谢谢.

编辑04/17/2012

提供更多信息:我的xml UI Designer在我的扩展SurfaceView类的中间显示了一个大框,称为MagnetView.我用红色概述了它.(Stackoverflow不允许我发布图片)

UI Designer视图( http://24.media.tumblr.com/tumblr_m2mmqvBNwW1qcreoco1_500.jpg)http://24.media.tumblr.com/tumblr_m2mmqvBNwW1qcreoco1_500.jpg

这是MagnetView(SurfaceView)类:

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.PixelFormat;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class MagnetView extends SurfaceView implements Runnable, SurfaceHolder.Callback{
Thread mThread;
SurfaceHolder mSurfaceHolder;
volatile boolean running = false;

//Creates new surface view as well as a new surfaceholder, which allows access to the surface
public MagnetView (Context context){
    super(context);

    mSurfaceHolder = getHolder();
            mSurfaceHolder.addCallback(this);
    //this.setZOrderOnTop(true);
    //getHolder().setFormat(PixelFormat.TRANSLUCENT);


}

public void resume(){
    running = true;
    mThread = new Thread(this);
    mThread.start();
}

public void pause(){
       boolean retry = true;
       running = false;
       while(retry){
        try {
         mThread.join();
         retry = false;
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
       }
}

@Override
public void run() {
  // TODO Auto-generated method stub
    while(running){
        if(mSurfaceHolder.getSurface().isValid()){
            Canvas canvas = mSurfaceHolder.lockCanvas();
            //... actual drawing on canvas

            canvas.drawARGB(100, 255, 255, 80);

            mSurfaceHolder.unlockCanvasAndPost(canvas);
        }
    }
}


@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {
    // TODO Auto-generated method stub

}

@Override
public void surfaceCreated(SurfaceHolder holder) {
    // TODO Auto-generated method stub
    this.resume();

}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    // TODO Auto-generated method stub

}

}

Answer 1

我只是简单地说明了这些变化.

1. 使用LinearLayout替换xml中的表面视图.

       <LinearLayout 
          android:id="@+id/middleSurface"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
       />
   

2. 获取线性布局的实例

   LinearLayout surface =(LinearLayout)findViewById(R.id.surface);

3. 将曲面视图的实例添加到LinearLayout

   surface.addView(new MagnetView(this));

在setContentView(R.layout.main)之后应该执行2,3个步骤;