Android獲取並設置Activity的亮度

此API只適合Android 2.1以上版本：

[java]

1. /**
2. * 判斷是否開啟了自動亮度調節
3. *
4. * @param aContext
5. * @return
6. */
7. public static boolean isAutoBrightness(ContentResolver aContentResolver) {
8. boolean automicBrightness = false;
9. try {
10. automicBrightness = Settings.System.getInt(aContentResolver,
11. Settings.System.SCREEN_BRIGHTNESS_MODE) == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC;
12. } catch (SettingNotFoundException e) {
13. e.printStackTrace();
14. }
15. return automicBrightness;
16. }
18. /**
19. * 獲取屏幕的亮度
20. *
21. * @param activity
22. * @return
23. */
24. public static int getScreenBrightness(Activity activity) {
25. int nowBrightnessValue = 0;
26. ContentResolver resolver = activity.getContentResolver();
27. try {
28. nowBrightnessValue = android.provider.Settings.System.getInt(
29. resolver, Settings.System.SCREEN_BRIGHTNESS);
30. } catch (Exception e) {
31. e.printStackTrace();
32. }
33. return nowBrightnessValue;
34. }
36. /**
37. * 設置亮度
38. *
39. * @param activity
40. * @param brightness
41. */
42. public static void setBrightness(Activity activity, int brightness) {
43. // Settings.System.putInt(activity.getContentResolver(),
44. // Settings.System.SCREEN_BRIGHTNESS_MODE,
45. // Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
46. WindowManager.LayoutParams lp = activity.getWindow().getAttributes();
47. lp.screenBrightness = Float.valueOf(brightness) * (1f / 255f);
48. activity.getWindow().setAttributes(lp);
49. }
51. /**
52. * 停止自動亮度調節
53. *
54. * @param activity
55. */
56. public static void stopAutoBrightness(Activity activity) {
57. Settings.System.putInt(activity.getContentResolver(),
58. Settings.System.SCREEN_BRIGHTNESS,
59. Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
60. }
62. /**
63. * 開啟亮度自動調節
64. *
65. * @param activity
66. */
67. public static void startAutoBrightness(Activity activity) {
68. Settings.System.putInt(activity.getContentResolver(),
69. Settings.System.SCREEN_BRIGHTNESS_MODE,
70. Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC);
71. }
73. /**
74. * 保存亮度設置狀態
75. *
76. * @param resolver
77. * @param brightness
78. */
79. public static void saveBrightness(ContentResolver resolver, int brightness) {
80. Uri uri = android.provider.Settings.System
81. .getUriFor("screen_brightness");
82. android.provider.Settings.System.putInt(resolver, "screen_brightness",
83. brightness);
84. resolver.notifyChange(uri, null);
85. }

[java]

1. sSeekBar = (SeekBar) findViewById(R.id.seek_bar);
2. sSeekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
4. @Override
5. public void onStopTrackingTouch(SeekBar seekBar) {
6. // TODO Auto-generated method stub
7. }
9. @Override
10. public void onStartTrackingTouch(SeekBar seekBar) {
12. }
14. @Override
15. public void onProgressChanged(SeekBar seekBar, int progress,
16. boolean fromUser) {
17. if (progress < 10) {
18. } else {
19. setBrightness(Test2Activity.this, progress);
20. }
21. }
22. });
24. //獲取當前亮度的位置
25. int a =getScreenBrightness(this);
26. sSeekBar.setProgress(a);

1. <SeekBar
2. android:id="@+id/seek_bar"
3. android:layout_width="200dp"
4. android:layout_height="wrap_content"
5. android:layout_alignParentBottom="true"
6. android:max="255"
7. android:maxHeight="8dp"
8. android:minHeight="8dp"
9. android:paddingBottom="5dp"
10. android:paddingLeft="13dp"
11. android:paddingRight="13dp"
12. android:progress="0"
13. />