动画覆盖相机活动预览

Question

我正在努力在我正在编码的Android练习应用中的相机预览活动上实现像动画(上下)这样的扫描仪线.

我已经成功地使动画代码在单个活动中工作 - 没有相机预览.无论我如何尝试我在stackoverflow或网上搜索的所有东西,我总是得到相机预览,但不是动画叠加.

这是我的xml文件:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
android:background="@android:color/transparent"
android:layout_centerInParent="true">

<SurfaceView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/imageView"
    android:src="@drawable/scanline"
    android:contentDescription="@string/scanline"
    android:layout_gravity="left|center_vertical"
    android:layout_alignParentStart="true"
    android:layout_alignParentEnd="true"
    android:background="@android:color/transparent"
    android:baselineAlignBottom="false"/>

<com.app.arsinoe.ui.widget.CameraPreview
    android:id="@+id/camera_preview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@android:color/transparent" />

<Button
    android:layout_width="156dp"
    android:layout_height="27dp"
    android:text="@string/exit_button"
    android:id="@+id/aboardButton2"
    android:layout_gravity="bottom|left"
    android:clickable="true"
    android:background="#4e0612"
    android:textColor="@android:color/white"
    android:textStyle="bold"
    android:alpha="1"
    android:paddingEnd="@dimen/activity_horizontal_margin"
    android:paddingStart="@dimen/activity_vertical_margin"
    android:onClick="exitButton"/>

<Button
    android:layout_width="310dp"
    android:layout_height="27dp"
    android:text="@string/scan_button"
    android:id="@+id/scanButton"
    android:layout_gravity="bottom|right"
    android:clickable="true"
    android:textColor="@android:color/white"
    android:textStyle="bold"
    android:alpha="1"
    android:background="#1b4a6c"
    android:paddingEnd="@dimen/activity_horizontal_margin"
    android:paddingStart="@dimen/activity_vertical_margin"
    android:onClick="scanButton"/>
</FrameLayout>

这是我的扫描仪线动画活动的工作代码:

public class ScanActivity extends Activity{


private View view;

protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.scan_activity);

    final Context readySnanner = this;
    Handler mHandler = new Handler();

    Runnable
            makeToast = new Runnable() {
        public void run() {
            Toast.makeText(readySnanner,
                    "Bla bla bla...", Toast.LENGTH_LONG).show();
        }
    };
    mHandler.postDelayed(makeToast, 4000);


    Toast.makeText(ScanActivity.this,"Bla bla... Please wait",      Toast.LENGTH_SHORT).show();


    ImageView animatedImage = (ImageView) findViewById(R.id.imageView);

    Animation animation
            = AnimationUtils.loadAnimation(this, R.anim.topdown);
    if (animation != null) {
        animatedImage.startAnimation(animation);}


    final int SPLASH_TIME;// 4 seconds
    SPLASH_TIME = 4 * 1000;


    boolean b;
    b = new Handler().postDelayed(new Runnable() {

        @Override
        public void run() {
        }
    }, SPLASH_TIME);
}


public void exitButton(View view) {

    this.finish();
    System.exit(0);
}

public void scanButton(View view) {

    Intent intent = new Intent(ScanActivity.this,
            B.class);
    startActivity(intent);
    ScanActivity.this.finish();
}

这是我的CameraActivity工作代码:

public class CameraActivity extends Activity {

private Camera camera;
private View view;
SurfaceView animatedImage;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.scan_activity);
    setResult(RESULT_CANCELED);
    // Camera may be in use by another activity or the system or not available   at all
    try {
        camera = getCameraInstance();
    } catch (Exception e) {
        e.printStackTrace();
    }
    if(cameraAvailable(camera)){
        initCameraPreview();
    } else {
        finish();
    }
}

// Show the camera view on the activity
private void initCameraPreview() {
    CameraPreview cameraPreview = (CameraPreview) findViewById(R.id.camera_preview);
    cameraPreview.init(camera);}

我不知道如何使用提供的xml文件将这两个活动作为单个活动一起运行.请帮助一个新手,因为我被困在这些问题上5天了!

我很抱歉没有提供图像来描述我正在尝试编码的内容,但我的声誉很小.任何回应,最好是工作样本,将不胜感激.

编辑

下图描绘了活动的布局:

红线应在动画中上下移动,超出相机预览.这是在ImageView中编码和工作,但不适用于CameraPreview.

这是我的CameraPreview活动,编辑为Juan-devtopia.coop建议:

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

private Context context;
private Camera camera;

public CameraPreview(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}

public CameraPreview(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public CameraPreview(Context context, Camera camera) {
    super(context);
    this.context = context;
    this.camera = camera;
}

public void init(Camera camera) {
    this.camera = camera;
    initSurfaceHolder();
}

@SuppressWarnings("deprecation") // needed for < 3.0
private void initSurfaceHolder() {
    SurfaceHolder holder = getHolder();
    if (holder != null) {
        holder.addCallback(this);
    }
    if (holder != null) {
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
    initCamera(holder);
}

private void initCamera(SurfaceHolder holder) {
    try {
        camera.setPreviewDisplay(holder);
        camera.startPreview();
    } catch (Exception ignored) {
    }
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}

public void setContext(Context context) {
    this.context = context;
}


public class Animation extends Activity {

    ImageView animatedImage = (ImageView) findViewById(R.id.imageView);

    android.view.animation.Animation animation;

    {
        animatedImage.startAnimation(animation);
        animation = AnimationUtils.loadAnimation(this, R.anim.topdown);
    }

 }

在编译并在设备上运行时,在logcat中我得到一个"java.lang.RuntimeException:无法实例化活动",由"引起:java.lang.InstantiationException:com.app.myapp.ui.widget.CameraPreview"引起.建议？

Answer 1

将其放置ImageView在与预览相同的布局中，以便它呈现在预览之上。然后将这两个代码放在同一个活动中，初始化相机预览的代码和动画动画的代码ImageView

将其视为布局中的CameraPreview另一个。View

换句话说，您初始化相机预览，就像在代码中一样，但也在那里启动动画，让您的初始化相机方法如下所示：

 // Show the camera view on the activity and show overlay animation
    private void initCameraPreview() {
        CameraPreview cameraPreview = (CameraPreview) findViewById(R.id.view);
        cameraPreview.init(camera);


        ImageView animatedImage = (ImageView) findViewById(R.id.imageView);
        Animation animation = AnimationUtils.loadAnimation(this, R.anim.rotate);
        animatedImage.startAnimation(animation);
    }

请注意，我更改了 id 和动画，因为我必须重新创建它来测试它。布局仅包含表面和图像视图，将图像视图放置在代码中的更下方（意味着它将在表面视图 上渲染）。

在我的代码示例中（我将其上传到 gitHub ），ic_launcher 只是在相机预览上旋转，但我假设使用您的动画并确保它循环而不是仅动画一次，应该可以工作。