谷歌视觉API条码扫描器删除相机视图

目前,我正在开发一个条码阅读器android应用程序与谷歌视觉API。我需要启动相机预览时,按钮被点击,直到按钮被点击屏幕应该是空的白色屏幕。当我尝试做这个相机预览的同时,屏幕上也出现了如何解决这个问题请帮助我。

public class MainActivity extends AppCompatActivity implements BarcodeRetriever {

// use a compound button so either checkbox or switch widgets work.


private static final String TAG = "BarcodeMain";


BarcodeCapture barcodeCapture;

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


    barcodeCapture = (BarcodeCapture) getSupportFragmentManager().findFragmentById(barcode);
    barcodeCapture.setRetrieval(this);


    findViewById(R.id.refresh).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            barcodeCapture.setShowDrawRect(true)
                    .setSupportMultipleScan(false)
                    .setTouchAsCallback(true)
                    .shouldAutoFocus(true)
                    .setShowFlash(true)
                    .setBarcodeFormat(Barcode.ALL_FORMATS)
                    .setCameraFacing(false ? CameraSource.CAMERA_FACING_FRONT : CameraSource.CAMERA_FACING_BACK)
                    .setShouldShowText(true);

            barcodeCapture.resume();
            barcodeCapture.refresh(true);
        }
    });

}


@Override
public void onRetrieved(final Barcode barcode) {
    Log.d(TAG, "Barcode read: " + barcode.displayValue);
    runOnUiThread(new Runnable() {
        @Override
        public void run() {

            AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this)
                    .setTitle("code retrieved")
                    .setMessage(barcode.displayValue);
            builder.show();
        }
    });
    barcodeCapture.stopScanning();


}

@Override
public void onRetrievedMultiple(final Barcode closetToClick, final List<BarcodeGraphic> barcodeGraphics) {
    runOnUiThread(new Runnable() {
        @Override
        public void run() {
            String message = "Code selected : " + closetToClick.displayValue + "\n\nother " +
                    "codes in frame include : \n";
            for (int index = 0; index < barcodeGraphics.size(); index++) {
                Barcode barcode = barcodeGraphics.get(index).getBarcode();
                message += (index + 1) + ". " + barcode.displayValue + "\n";
            }
            AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this)
                    .setTitle("code retrieved")
                    .setMessage(message);
            builder.show();
        }
    });

}

@Override
public void onBitmapScanned(SparseArray<Barcode> sparseArray) {
    for (int i = 0; i < sparseArray.size(); i++) {
        Barcode barcode = sparseArray.valueAt(i);
        Log.e("value", barcode.displayValue);
    }

}

@Override
public void onRetrievedFailed(String reason) {

}

@Override
public void onPermissionRequestDenied() {

}

我的activity\u main.xml文件

   <?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=".MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@+id/actions"
        android:layout_weight="1"
        android:gravity="center">

        <fragment
            android:id="@+id/barcode"
       android:name="com.google.android.gms.samples.vision.barcodereader.BarcodeCapture"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            app:gvb_auto_focus="true"
            app:gvb_code_format="code_39|aztec"
            app:gvb_flash="false"
            app:gvb_rect_colors="@array/rect_color" />
    </RelativeLayout>

    <LinearLayout
        android:id="@+id/actions"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:orientation="vertical"
        android:paddingLeft="16dp"
        android:layout_gravity="center_vertical"
        android:gravity="center_vertical"
        android:padding="20dp"
        android:paddingRight="16dp">

        <RelativeLayout
            android:id="@+id/refresh"
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:layout_marginLeft="40dp"
            android:layout_marginRight="40dp"
            android:layout_gravity="center_vertical"
            android:gravity="center_vertical"
            android:background="@drawable/circle_layout_for_start_scan">

        </RelativeLayout>
    </LinearLayout>
</RelativeLayout>