Question

我使用运行相机的库。需要确保相机全屏工作。为此，请写下

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Initialize and start the bar code recognition.
        initializeAndStartBarcodeScanning();
    }



public void initializeAndStartBarcodeScanning() {
            // Switch to full screen.
            getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
            supportRequestWindowFeature(Window.FEATURE_NO_TITLE);

            // We instantiate the automatically adjusting barcode picker that will
            // choose the correct picker to instantiate. Be aware that this picker
            // should only be instantiated if the picker is shown full screen as the
            // legacy picker will rotate the orientation and not properly work in
            // non-fullscreen.
            ScanditSDKAutoAdjustingBarcodePicker picker = new ScanditSDKAutoAdjustingBarcodePicker(
                    this, sScanditSdkAppKey, ScanditSDKAutoAdjustingBarcodePicker.CAMERA_FACING_BACK);

            // Add both views to activity, with the scan GUI on top.
            setContentView(picker);
            mBarcodePicker = picker;

            // Register listener, in order to be notified about relevant events
            // (e.g. a successfully scanned bar code).
            mBarcodePicker.getOverlayView().addListener(this);

            // Show a search bar in the scan user interface.
            mBarcodePicker.getOverlayView().showSearchBar(true);
        }

并收到错误

02-03 16:08:59.089    6890-6890/com.skip.client.customer E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.skip.client.customer, PID: 6890
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.skip.client.customer/com.skip.client.customer.activities.ScanActivity}: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2318)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2396)
            at android.app.ActivityThread.access$800(ActivityThread.java:139)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1293)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:149)
            at android.app.ActivityThread.main(ActivityThread.java:5268)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: android.util.AndroidRuntimeException: requestFeature() must be called before adding content
            at com.android.internal.policy.impl.PhoneWindow.requestFeature(PhoneWindow.java:249)
            at android.app.Activity.requestWindowFeature(Activity.java:3371)
            at android.support.v7.app.ActionBarActivityDelegateBase.supportRequestWindowFeature(ActionBarActivityDelegateBase.java:460)
            at android.support.v7.app.ActionBarActivity.supportRequestWindowFeature(ActionBarActivity.java:194)
            at com.skip.client.customer.activities.ScanActivity.initializeAndStartBarcodeScanning(ScanActivity.java:53)
            at com.skip.client.customer.activities.ScanActivity.onCreate(ScanActivity.java:30)
            at android.app.Activity.performCreate(Activity.java:5411)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2270)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2396)
            at android.app.ActivityThread.access$800(ActivityThread.java:139)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1293)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:149)
            at android.app.ActivityThread.main(ActivityThread.java:5268)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
            at dalvik.system.NativeStart.main(Native Method)

行上的错误

supportRequestWindowFeature(Window.FEATURE_NO_TITLE);

如果我在方法之前调用此行，则所有工作

@Override
    protected void onCreate(Bundle savedInstanceState) {
        supportRequestWindowFeature(Window.FEATURE_NO_TITLE); 
        super.onCreate(savedInstanceState);
        // Initialize and start the bar code recognition.
        initializeAndStartBarcodeScanning();
    }

但是你不能这样做？我是对的吗？

Answer 1

因为您在supportRequestWindowFeature之前调用了super.onCreate，所以无需在initializeAndStartBarcodeScanning方法中再次调用它。

@Override
    protected void onCreate(Bundle savedInstanceState) {
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, 
                             WindowManager.LayoutParams.FLAG_FULLSCREEN);
            supportRequestWindowFeature(Window.FEATURE_NO_TITLE);
        super.onCreate(savedInstanceState);
        // Initialize and start the bar code recognition.
        initializeAndStartBarcodeScanning();
    }
public void initializeAndStartBarcodeScanning() {
 .....
}

尝试删除Window.FEATURE_NO_TITLE时出错

1 个答案: