我在三星Galaxy相机上测试我的相机应用程序，但我正在尝试开启Flash 获取 开启手电筒时出现异常< / em> ，因为我在catch块中使用此消息..
Note:- Camera always in running mode
为什么我无法在我的应用中 ON Flash ，我使用两个不同的按钮，一个用于 捕获图像 ，仅次于 控制闪光灯 （ON＆amp; OFF）。
行号 199 是：
mCamera.setParameters(p);
行号 140 是：
turnOnFlashLight();
CameraLauncherActivity.java -
flashButton = (ImageButton) findViewById(R.id.btnFlash);
Log.d(CameraLauncherActivity.LOG_TAG, "SingleAngelActivityButton :: " + viewButton);
flashButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (isFlashOn) {
// turn off flash
turnOffFlashLight();
} else {
// turn on flash
turnOnFlashLight();
}
}
});
cd = new ConnectionDetector(getApplicationContext());
// Check if Internet present
if (!cd.isConnectingToInternet()) {
// Internet Connection is not present
alert.showAlertDialog(CameraLauncherActivity.this, "Internet Connection Error",
"Please connect to working Internet connection", false);
// stop executing code by return
return;
}
checkFlash();
// calling background thread
new LoadSingleTrack().execute();
}
@SuppressWarnings("deprecation")
public void checkFlash()
{
/*
* First check if device is supporting flashlight or not
*/
hasFlash = getApplicationContext().getPackageManager()
.hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
if (!hasFlash) {
// device doesn't support flash
// Show alert message and close the application
AlertDialog alert = new AlertDialog.Builder(CameraLauncherActivity.this)
.create();
alert.setTitle("Error");
alert.setMessage("Sorry, your device doesn't support flash light!");
alert.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// closing the application
finish();
}
});
alert.show();
return;
}
}
public void turnOnFlashLight() {
try {
if (getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)) {
Parameters p = mCamera.getParameters();
p.setFlashMode(Parameters.FLASH_MODE_TORCH);
mCamera.setParameters(p);
isFlashOn = true;
toggleButtonImage();
}
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(getBaseContext(), "Exception throws in turning on flashlight.", Toast.LENGTH_SHORT).show();
}
}
public void turnOffFlashLight() {
try {
if (getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)) {
isFlashOn = false;
toggleButtonImage();
}
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(getBaseContext(), "Exception throws in turning off flashlight.", Toast.LENGTH_SHORT).show();
}
}
private void toggleButtonImage(){
if(isFlashOn){
flashButton.setImageResource(R.drawable.green_button);
}else{
flashButton.setImageResource(R.drawable.red_button);
}
}
private Camera getCameraInstance() {
Camera camera = null;
try {
camera = Camera.open(0);
} catch (Exception e) {
// cannot get camera or does not exist
}
if(camera!=null){
Camera.Parameters parameters = camera.getParameters();
camera.setParameters(parameters);
}
return camera;
}
PreviewSurface.java -
public class PreviewSurface extends SurfaceView implements
SurfaceHolder.Callback {
public static final String LOG_TAG = "CameraPreview";
private SurfaceHolder mSurfaceHolder;
private Camera mCamera;
// Constructor that obtains context and camera
@SuppressWarnings("deprecation")
public PreviewSurface(Context context, Camera camera) {
super(context);
this.mCamera = camera;
this.mSurfaceHolder = this.getHolder();
this.mSurfaceHolder.addCallback(this);
this.mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
this.mSurfaceHolder.setFixedSize(100, 100);
}
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
try {
Camera.Parameters parameters = mCamera.getParameters();
if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE)
{
parameters.set("orientation", "portrait");
mCamera.setDisplayOrientation(90);
parameters.setRotation(90);
mCamera.setPreviewDisplay(surfaceHolder);
mCamera.startPreview();
}
else
{
// This is an undocumented although widely known feature
parameters.set("orientation", "landscape");
// For Android 2.2 and above
mCamera.setDisplayOrientation(0);
// Uncomment for Android 2.0 and above
parameters.setRotation(0);
}
mCamera.setPreviewDisplay(surfaceHolder);
mCamera.startPreview();
} catch (IOException e) {
// left blank for now
}
}
@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
mCamera.stopPreview();
mCamera.release();
}
@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int format,
int width, int height) {
try {
Camera.Parameters parameters = mCamera.getParameters();
if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
parameters.set("orientation", "portrait");
mCamera.setDisplayOrientation(90);
parameters.setRotation(90);
}
else {
// This is an undocumented although widely known feature
parameters.set("orientation", "landscape");
// For Android 2.2 and above
mCamera.setDisplayOrientation(0);
// Uncomment for Android 2.0 and above
parameters.setRotation(0);
}
mCamera.setPreviewDisplay(surfaceHolder);
mCamera.startPreview();
} catch (IOException e) {
// left blank for now
}
}
}
日志说：
12-17 18:12:56.485: W/System.err(18918): java.lang.RuntimeException: setParameters failed
12-17 18:12:56.485: W/System.err(18918): at android.hardware.Camera.native_setParameters(Native Method)
12-17 18:12:56.485: W/System.err(18918): at android.hardware.Camera.setParameters(Camera.java:1475)
12-17 18:12:56.485: W/System.err(18918): at com.example.camera.CameraLauncherActivity.turnOnFlashLight(CameraLauncherActivity.java:199)
12-17 18:12:56.485: W/System.err(18918): at com.example.camera.CameraLauncherActivity$4.onClick(CameraLauncherActivity.java:140)
12-17 18:12:56.485: W/System.err(18918): at android.view.View.performClick(View.java:4223)
12-17 18:12:56.485: W/System.err(18918): at android.view.View$PerformClick.run(View.java:17275)
12-17 18:12:56.485: W/System.err(18918): at android.os.Handler.handleCallback(Handler.java:615)
12-17 18:12:56.485: W/System.err(18918): at android.os.Handler.dispatchMessage(Handler.java:92)
12-17 18:12:56.485: W/System.err(18918): at android.os.Looper.loop(Looper.java:137)
12-17 18:12:56.485: W/System.err(18918): at android.app.ActivityThread.main(ActivityThread.java:4921)
12-17 18:12:56.485: W/System.err(18918): at java.lang.reflect.Method.invokeNative(Native Method)
12-17 18:12:56.485: W/System.err(18918): at java.lang.reflect.Method.invoke(Method.java:511)
12-17 18:12:56.485: W/System.err(18918): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1036)
12-17 18:12:56.485: W/System.err(18918): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:803)
12-17 18:12:56.485: W/System.err(18918): at dalvik.system.NativeStart.main(Native Method)
12-17 18:13:29.370: W/IInputConnectionWrapper(18918): getSelectedText on inactive InputConnection
12-17 18:13:29.375: W/IInputConnectionWrapper(18918): setComposingText on inactive InputConnection