我一直在为安卓制作一个手电筒应用程序,遇到了一些问题,并能够解决这些问题。但现在,当我运行该应用程序时,它会加载到我的HTC one上,并运行良好,直到我第四次按下手电筒电源按钮。我可以按一次,它就会打开。我按第二次,它会关闭。我按了第三次,它又会打开。我按第四次,它不会关闭?帮助
public class MainActivity extends Activity {
ImageButton powerButton;
private Camera camera;
private boolean isFlashOn;
private boolean hasFlash;
Parameters params;
@TargetApi(Build.VERSION_CODES.ECLAIR)
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
powerButton = (ImageButton) findViewById(R.id.power_button);
hasFlash = getApplicationContext().getPackageManager()
.hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
if (!hasFlash) {
AlertDialog alert = new AlertDialog.Builder(MainActivity.this)
.create();
alert.setTitle("Notice");
alert.setMessage("I'm sorry, your device doesn't support flashlight!");
alert.setButton("Done", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
alert.show();
return;
}
getCamera();
toggleButtonImage();
powerButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (isFlashOn) {
turnOffFlash();
} else {
turnOnFlash();
}
}
});
}
private void getCamera() {
if (camera == null) {
try {
camera = Camera.open();
params = camera.getParameters();
} catch (RuntimeException e) {
Log.e("Failed to open camera. Alert: ", e.getMessage());
}
}
}
public void turnOnFlash() {
if (!isFlashOn) {
if (camera == null || params == null) {
return;
}
params = camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_TORCH);
camera.setParameters(params);
camera.startPreview();
isFlashOn = true;
toggleButtonImage();
}
}
private void turnOffFlash() {
if (isFlashOn) {
if (camera == null || params == null) {
return;
}
params = camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_OFF);
camera.setParameters(params);
camera.stopPreview();
isFlashOn = false;
toggleButtonImage();
}
}
private void toggleButtonImage(){
if(isFlashOn){
powerButton.setImageResource(R.drawable.flashlight_on);
}else{
powerButton.setImageResource(R.drawable.flashlight_off);
}
}
@Override
protected void onDestroy() {
super.onDestroy();
}
@Override
protected void onPause() {
super.onPause();
turnOffFlash();
}
@Override
protected void onRestart() {
super.onRestart();
}
@Override
protected void onResume() {
super.onResume();
if(hasFlash)
turnOffFlash();
}
@Override
protected void onStart() {
super.onStart();
getCamera();
}
@Override
protected void onStop() {
super.onStop();
if (camera != null) {
camera.release();
camera = null;
}
}
'清单-http://pastebin.com/Tw6LTemP'Activity_min.xml-http://pastebin.com/Tga1agN7
至于您描述的症状,可能是SurfaceView崩溃。请从logcat发布您的错误日志。
此外,你在onResume((中的代码对我来说没有意义(尽管,这不是你问题的直接原因,对于你问题的原因,请再次查看你的日志(:
@Override
protected void onResume() {
super.onResume();
if(hasFlash)
turnOffFlash();
}
我想你的意思是说如果(isFlashOn(关闭Flash((;但即使你纠正了这一点,那仍然是错误的。
我用来关闭手电筒的代码是:
private void turnOffFlash() {
if (isFlashOn) {
if (camera == null || params == null) {
return;
}
params = camera.getParameters();
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
camera.setParameters(params);
camera.stopPreview();
isFlashOn = false;
}
}