FlashLight应用程序无法连接到照相机服务

Question

这是我的密码：

我添加了一个github权限代码，但它仍然崩溃

我做了每一件事，但每次都会崩溃

我还在我的舱单上增加了对照相机的许可。

                    parameter = camera.getParameters();
                }
                @Override public void onPermissionDenied(PermissionDeniedResponse response) {
                    Toast.makeText(getApplicationContext(), "Permission Denied", Toast.LENGTH_SHORT).show();
                    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                    builder.setMessage("App needs permission to access camera")
                            .setPositiveButton("Granted", new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog, int id) {
                                    Intent myAppSettings = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + getPackageName()));
                                    myAppSettings.addCategory(Intent.CATEGORY_DEFAULT);
                                    myAppSettings.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                                    startActivity(myAppSettings);

                                }
                            }).setNegativeButton("Denied", new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                        }
                    }).create().show();
                }
                @Override public void onPermissionRationaleShouldBeShown(PermissionRequest permission, PermissionToken token)
                {[enter image description here][1]
                    token.continuePermissionRequest();
                }

            }).check();





    //getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
    textview = (TextView) findViewById(R.id.textView);
    flashLight = (ImageButton) findViewById(R.id.flash_light);

// setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT)；

    //askPermission(CAMERA,camera1);






    flashLight.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (!isFlashLightOn) {
                turnOnTheFlash();
            } else {
                turnOffTheFlash();
            }
        }
    });

logCat：

09-30 18:59:31.698 11339-11339/inducesmile.com.androidflashlightapp E/AndroidRuntime:致命异常:主要进程: inducesmile.com.androidflashlightapp，PID: 11339 java.lang.RuntimeException:无法恢复活动{inducesmile.com.androidflashlightapp/inducesmile.com.androidflashlightapp.MainActivity}：java.lang.RuntimeException:未能连接到照相机服务在android.app.ActivityThread.performResumeActivity(ActivityThread.java:3506) at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3546)在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2795) at android.app.ActivityThread.-wrap12(ActivityThread.java)在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527) at android.os.Handler.dispatchMessage(Handler.java:110)在android.app.ActivityThread.main(ActivityThread.java:6251)的android.os.Looper.loop(Looper.java:203)在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1073)的java.lang.reflect.Method.invoke(原生方法)在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934)，由: java.lang.RuntimeException:未能连接到照相机服务android.hardware.Camera.(Camera.java:647) at android.hardware.Camera.open(Camera.java:510)在inducesmile.com.androidflashlightapp.MainActivity.turnOffTheFlash(MainActivity.java:105) at inducesmile.com.androidflashlightapp.MainActivity.onResume(MainActivity.java:165)在android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1269) at android.app.Activity.performResume(Activity.java:6791)在android.app.ActivityThread.performResumeActivity(ActivityThread.java:3477) at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3546)在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2795)(在android.app.ActivityThread.-wrap12(ActivityThread.java))在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527)(在android.os.Handler.dispatchMessage(Handler.java:110))在android.app.ActivityThread.main(ActivityThread.java:6251)的android.os.Looper.loop(Looper.java:203)在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1073)的java.lang.reflect.Method.invoke(本地方法)在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934) 09-30 18:59:31.804 11339-11347/inducesmile.com.androidflashlightapp I/art: Enter循环。

Answer 1

几个月前，我还开发了一个基于手电筒传感器的应用程序。我已经为手电筒活动的代码(包括java和xml)创建了gist，而且它似乎运行得很好。看看下面的链接，看看它是否有帮助：

https://gist.github.com/robillo/b27d37be3262164ee7f5532230c28c5a

https://gist.github.com/robillo/71afef65923138ed9d6011e3bd216249

另外，尝试在onCreate()中的if块中处理活动的一部分，例如：

askForPermissions();
if(checkForPermission()){
    //Do your processing here
}

这些职能是：

void askForPermissions(){
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if(getActivity().checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
            getActivity().requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.READ_EXTERNAL_STORAGE}, PERMISSION_REQUEST_CODE);
        }
    }
}

boolean checkForPermission(){
    return Build.VERSION.SDK_INT >= Build.VERSION_CODES.M;
}

Answer 2

如果不看到您的turnOnTheFlash和turnOffTheFlash函数，很难判断，但我猜您在某些时候没有正确地释放相机，如文档所示。