Question

当设备接到来电时，我试图让LED闪光灯闪烁。这就是我在服务类中的做法。

public class MyService extends Service {
Camera cam = null;
boolean offhook = false;

@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {

    String state = intent.getStringExtra("state");

    if (TelephonyManager.EXTRA_STATE_RINGING.equals(state)) {
        if (getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH) && !offhook) {


                String myString = "01010101010101010101";
                long blinkDelay = 50;



                for (int i = 0; i < myString.length(); i++) {
                    if (myString.charAt(i) == '0') {
                        // params.setFlashMode(Camera.Parameters.FLASH_MODE_ON);
                        cam = Camera.open();
                        Camera.Parameters p = cam.getParameters();
                        p.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
                        cam.setParameters(p);
                    } else {
                        // params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
                        offhook = true;
                        if (cam != null) {
                            cam.stopPreview();
                            cam.release();
                            cam = null;
                        }
                        this.stopSelf();
                    }

                    try {
                        Thread.sleep(blinkDelay);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }



        }
    }

    if (TelephonyManager.EXTRA_STATE_IDLE.equals(state)) {
        if (!offhook) {
            if (cam != null) {
                cam.release();
                cam = null;
            }
            this.stopSelf();
        } else {
            offhook = false;
        }
    }

    if (TelephonyManager.EXTRA_STATE_OFFHOOK.equals(state)) {
        offhook = true;
        if (cam != null) {
            cam.stopPreview();
            cam.release();
            cam = null;
        }
        this.stopSelf();
    }

    return super.onStartCommand(intent, flags, startId);
}

@Override
public void onDestroy() {
    if (cam != null) {
        cam.release();
        cam = null;
    }
    super.onDestroy();
}
}

但即使在我参加或拒绝接听电话之后，眨眼也没有停止，因为它处于for循环中。我该怎么做？

Answer 1

不要在onStartCommand中编写代码，因为此方法将在主线程上执行，因此很可能会得到ANR。要停止LED闪烁，请在应答或拒绝呼叫时中断线程，并使循环中断退出循环。

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1 个答案: