让相机灯闪烁
Make camera light flash
我想让相机闪光灯。我的代码将使它在按下一个按钮时闪烁得很好,但如果我在它完成闪烁之前再次按下按钮,它会使我的应用程序崩溃。我想我需要以某种方式检查它是否仍在闪烁,然后再尝试再次启动闪光灯。
public class BlinkBack {
public static void blink(MainActivity ma){
if (ma.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)){
final Camera mCamera = Camera.open();
new CountDownTimer(5000, 100) {
int counter = 0;
public void onTick(long millisUntilFinished) {
if (counter % 2 == 0) {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(params);
mCamera.startPreview();
}
else {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
}
counter++;
}
public void onFinish() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
mCamera.release();
}
}.start();
}
}
}
我找到了自己的答案。最终相机 mCamera = Camera.open();有一个未经检查的 RunTimeException 所以我只是用 try catch 吃了那个异常并修复了它
public class BlinkBack {
public static void blink(MainActivity ma){
if (ma.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)){
try {
final Camera mCamera = Camera.open();
new CountDownTimer(5000, 100) {
int counter = 0;
public void onTick(long millisUntilFinished) {
if (counter % 2 == 0) {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(params);
mCamera.startPreview();
}
else {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
}
counter++;
}
public void onFinish() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
mCamera.release();
}
}.start();
}
catch (Exception e) {
e.printStackTrace();
}
}
}
}
我想让相机闪光灯。我的代码将使它在按下一个按钮时闪烁得很好,但如果我在它完成闪烁之前再次按下按钮,它会使我的应用程序崩溃。我想我需要以某种方式检查它是否仍在闪烁,然后再尝试再次启动闪光灯。
public class BlinkBack {
public static void blink(MainActivity ma){
if (ma.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)){
final Camera mCamera = Camera.open();
new CountDownTimer(5000, 100) {
int counter = 0;
public void onTick(long millisUntilFinished) {
if (counter % 2 == 0) {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(params);
mCamera.startPreview();
}
else {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
}
counter++;
}
public void onFinish() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
mCamera.release();
}
}.start();
}
}
}
我找到了自己的答案。最终相机 mCamera = Camera.open();有一个未经检查的 RunTimeException 所以我只是用 try catch 吃了那个异常并修复了它
public class BlinkBack {
public static void blink(MainActivity ma){
if (ma.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)){
try {
final Camera mCamera = Camera.open();
new CountDownTimer(5000, 100) {
int counter = 0;
public void onTick(long millisUntilFinished) {
if (counter % 2 == 0) {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(params);
mCamera.startPreview();
}
else {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
}
counter++;
}
public void onFinish() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
mCamera.setParameters(params);
mCamera.stopPreview();
mCamera.release();
}
}.start();
}
catch (Exception e) {
e.printStackTrace();
}
}
}
}