android – 无法在片段中启动qrCode Camera scanner

我有两个碎片,其中一个我想要一个QRcode扫描仪(使用ZXingScannerView).但是,相机无法启动,我只能看到黑屏.这是我的实现：

QRCodeReaderFragment.java

private ZXingScannerView mScannerView;
private LinearLayout qrCameraLayout;

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

@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {

    View fragmentView =  inflater.inflate(R.layout.fragment_qr_code_reader,container,false);

    qrCameraLayout = (LinearLayout) fragmentView.findViewById(R.id.ll_qrcamera);

    mScannerView = new ZXingScannerView(getActivity().getApplicationContext());

    mScannerView.setLayoutParams(new LinearLayout.LayoutParams(
            LinearLayout.LayoutParams.MATCH_PARENT,LinearLayout.LayoutParams.MATCH_PARENT));

    qrCameraLayout.addView(mScannerView);

    return fragmentView;
}

fragment_qr_code_reader.xml

<FrameLayout 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"
    tools:context="com.letsguang.android.shoppingmalltenant.fragment.QrCodeReaderFragment"
    android:id="@+id/fl_qrcamera"
    >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:id="@+id/ll_qrcamera"
        android:orientation="vertical">




    </LinearLayout>

</FrameLayout>

解决方法

您没有设置视图.根据 https://github.com/dm77/barcodescanner的文档,您必须在onResume / onPause中启动/停止相机：

@Override
public void onResume() {
    super.onResume();
    mScannerView.setResultHandler(this);
    mScannerView.startCamera();
}

@Override
public void onPause() {
    super.onPause();
    mScannerView.stopCamera();
}