利用GSensor让屏幕实现360度旋转 - liangshengyang的专栏 - CSDN博客

1、您还未登录!|CSDN 首页资讯论坛博客下载搜索更多公告:CSDN 社区招聘.Net 开发工程师、运营专员,UI 设计师在Android 的Settings-Sound and Display 中有Orientation 这一设置项,反转手机,手机屏幕会随之旋转,一般只可以旋转90度。这一settings 设置是在文件SoundAndDisplaySettings.java 中,该项对应串为:view plaincopy to clipboardprint?1. private static final String KEY_ACCELEROMETER = accelerom 其默认值保存在x

2、ml 文件中,默认是Enable 。UI 程序初始化时会根据其值是框中打勾(代码在onCreate 函数中:view plaincopy to clipboardprint?1. protected void onCreate(Bundle savedInstanceState 2. 3. mAccelerometer = (CheckBoxPreference findPreferenc CELEROMETER; 4. mAccelerometer.setPersistent(false; 5. 6. 当用户改变了该值时,会保存起来: 利用GSensor 让屏幕实现360度旋转 收藏lian

3、gshengyang 的专栏登录注册空间博客好友相册留言用户操作留言 发消息 加为 ,ID :liangshengyang 共5242次访问,排名2万外人,关注者4人。,qq:,的文章原创 18 篇翻译 0 篇转载 1 篇评论 9 篇订阅我的博客2011/5/19利用GSensor 让屏幕实现360度旋转 - lia view plaincopy to clipboardprint?1. public boolean onPreferenceTreeClick(PreferenceScreen prefeeen, Preference preference 2. 3. else if (pre

4、ference = mAccelerometer 4. Settings.System.putInt(getContentResolver(,5. Settings.System.ACCELEROMETER_ROTATION6. mAccelerometer.isChecked( ? 1 : 0;7. 8. 文件frameworks/policies/base/phone/com/android/internal/policy/eWindowManager.java中的SettingsServer会随时监控其值,对用户设置:view plaincopy to clipboardprint?1.

5、 public void update( 2. ContentResolver resolver = mContext.getContentRe3. boolean updateRotation = false;4. synchronized (mLock 5. 6. int accelerometerDefault = Settings.System.getIn,7. Settings.System.ACCELEROMETER_ROTATIOULT_ACCELEROMETER_ROTATION;8. if (mAccelerometerDefault != accelerometerDefa

6、u9. mAccelerometerDefault = accelerometerDefau10. updateOrientationListenerLp(;11. 12. 13. 上述是设置生效流程。当Orientation设置Enable时,会发生什么呢?liangshengyang的公告文章分类AndroidC/C+/LinuxGitGstreamer存档2011年02月(52011年01月(12010年11月(12010年09月(42010年08月(12010年07月(72011/5/19利用GSensor让屏幕实现360度旋转 - lia在PhoneWindowManager.jav

7、a有个Listener,它会根据Sensor判别出的,调用WindowManager.setRotation让屏幕进行旋转。另外,当应用程序屏幕旋转时则不会旋转,见函数needSensorRunningLp(。view plaincopy to clipboardprint?1. class MyOrientationListener extends WindowOrientationListen2. MyOrientationListener(Context context 3. super(context;4. 5.6. Override7. public void onOrientati

8、onChanged(int rotation 8. / Send updates based on orientation value9. if (true Log.i(TAG, onOrientationChanged, rotation co +rotation;10. try 11. mWindowManager.setRotation(rotation, false,12. mFancyRotationAnimation;13. catch (RemoteException e 14. / Ignore15. 16. 17. 18. MyOrientationListener mOri

9、entationListener;19. boolean useSensorForOrientationLp(int appOrientation 20. if (appOrientation = ActivityInfo.SCREEN_ORIENTATIOR 21. return true;22. 23. if (mAccelerometerDefault != 0 & (24. appOrientation = ActivityInfo.SCREEN_ORIENTATR |25. appOrientation = ActivityInfo.SCREEN_ORIENTATPECIFIED 2

10、6. return true;27. 28. return false;29. 30.31. /*32. * We always let the sensor be switched on by default exce33. * the user has explicitly disabled sensor based rotation or34. * screen is switched off.35. */36. boolean needSensorRunningLp( 37. if (mCurrentAppOrientation = ActivityInfo.SCREEN_ORN_SE

11、NSOR 38. / If the application has explicitly requested to follow t39. / orientation, then we need to turn the sensor or.40. return true;41. 42. if (mAccelerometerDefault = 0 43. / If the setting for using the sensor by default is ena44. / we will always leave it on. Note that the user could45. / a w

12、indow that forces an orientation that does not u46. / sensor and in theory we could turn it off. howeverext47. / turning it on we wont have a good value for the cu48. / orientation for a little bit, which can cause orientati49. / changes to lag, so wed like to keep it always on. (50. / still be turn

13、ed off when the screen is off.51. return false;52. 53. return true;54. 在WindowOrientationListener(见文件javaframeworks/base/core/ja d/view/WindowOrientationListener.java中会监听Sensor的值,对旋行判断,然后调用抽象方法onOrientationChanged,因此,只要在子类重新实现这个函数即可对四个不同方向做出响应(见上面让屏幕旋转即是一遗憾的是在Donut和clair中,对旋转方向的识别只给出了90度旋转,在了一个270度旋

14、转,不支持180度即倒立的操作。可以在修改下面代码,判断来自于Gsensor的值,识别出旋转方向:view plaincopy to clipboardprint?1. public void onSensorChanged(SensorEvent event 2. float values = event.values;3. float X = values_DATA_X;4. float Y = values_DATA_Y;5. float Z = values_DATA_Z;6. float OneEightyOverPi = 57.29577957855f;7. float gravi

15、ty = (float Math.sqrt(X*X+Y*Y+Z*Z;8. float zyangle = (floatMath.asin(Z/gravity*OneEightyOve9. int rotation = -1;10. if (zyangle = PIVOT_LO11. / Check orientation only if the phone is flat enough12. / Dont trust the angle if the magnitude is small compae y value13. float angle = (floatMath.atan2(Y, -

16、X * OneEightyOver14. int orientation = 90 - (intMath.round(angle;15. / normalize to 0 - 359 range16. while (orientation = 360 17. orientation -= 360;18. 19. while (orientation = PL_LOWER & (orientation = LP_UP float threshold; float delta = zyangle - PIVOT; if (mSensorRotation = Surface.ROTATION_90

17、if (delta = threshold ? Surface.RO _0 : Surface.ROTATION_90; else if (delta 0 / Delta is negative else threshold = PL_UPPER-(PL_LF_UPPER * delta; threshold = PL_UPPER+(PL_LF_LOWER * delta; rotation = (orientation = LANDSCAPE_LOWER & (orien LP_LOWER rotation = Surface.ROTATION_90; else if (orientatio

18、n = PL_UPPER | (orientation = P T_LOWER rotation = Surface.ROTATION_0; if (rotation != -1 & (rotation != mSensorRotation mSensorRotation = rotation; 6/8 2011/5/19 利用GSensor让屏幕实现360度旋转 - lia 54. 55. 56. 57. onOrientationChanged(mSensorRotation; 在Froyo中，对上述算法进行了修改，让其报出270度的旋转方向。 发表于 2010年09月22日 11:10:00 | 评论( 1 | 举报 旧一篇:Android中Native代码SIGSEGV调试-调用堆栈解