如何使LED手电筒在通话接收时闪烁

Question

我正在尝试使LED闪光灯在设备收到来电时闪烁。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();
}
}

但是即使在我参加或拒绝呼叫后，眨眼也不会停止，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，因此您可能会获得 ANR。要停止 LED 闪烁，请在接听或拒绝呼叫时中断线程，并放置一个 for 循环中断以退出循环。