Adjust the screen brightness of an Android phone

Paste a code to adjust the screen brightness of your Android phone. For details, see:

public void setBrightness(int level) {ContentResolver cr = getContentResolver();Settings.System.putInt(cr, "screen_brightness", level);try {defaultLevel = Settings.System.getInt(cr, "screen_brightness");} catch (SettingNotFoundException e) {e.printStackTrace();}Window window = getWindow();LayoutParams attributes = window.getAttributes();float flevel = level;attributes.screenBrightness = flevel / 255;getWindow().setAttributes(attributes);}

In addition, the uimodemanager class provides the control system UI mode service. For details, refer:

{UiModeManager uim = (UiModeManager) getSystemService(Context.UI_MODE_SERVICE);int i = uim.getCurrentModeType();if (i != Configuration.UI_MODE_TYPE_CAR) {uim.enableCarMode(0);}uim.setNightMode(UiModeManager.MODE_NIGHT_YES);}

For the uimodemanager code, see:

package android.app;import android.content.Context;import android.content.res.Configuration;import android.os.RemoteException;import android.os.ServiceManager;import android.util.Log;/** * This class provides access to the system uimode services.  These services * allow applications to control UI modes of the device. * It provides functionality to disable the car mode and it gives access to the * night mode settings. *  * <p>These facilities are built on top of the underlying * {@link android.content.Intent#ACTION_DOCK_EVENT} broadcasts that are sent when the user * physical places the device into and out of a dock.  When that happens, * the UiModeManager switches the system {@link android.content.res.Configuration} * to the appropriate UI mode, sends broadcasts about the mode switch, and * starts the corresponding mode activity if appropriate.  See the * broadcasts {@link #ACTION_ENTER_CAR_MODE} and * {@link #ACTION_ENTER_DESK_MODE} for more information. *  * <p>In addition, the user may manually switch the system to car mode without * physically being in a dock.  While in car mode -- whether by manual action * from the user or being physically placed in a dock -- a notification is * displayed allowing the user to exit dock mode.  Thus the dock mode * represented here may be different than the current state of the underlying * dock event broadcast. * * <p>You do not instantiate this class directly; instead, retrieve it through * {@link android.content.Context#getSystemService * Context.getSystemService(Context.UI_MODE_SERVICE)}. */public class UiModeManager {    private static final String TAG = "UiModeManager";    /**     * Broadcast sent when the device's UI has switched to car mode, either     * by being placed in a car dock or explicit action of the user.  After     * sending the broadcast, the system will start the intent     * {@link android.content.Intent#ACTION_MAIN} with category     * {@link android.content.Intent#CATEGORY_CAR_DOCK}     * to display the car UI, which typically what an application would     * implement to provide their own interface.  However, applications can     * also monitor this Intent in order to be informed of mode changes or     * prevent the normal car UI from being displayed by setting the result     * of the broadcast to {@link Activity#RESULT_CANCELED}.     */    public static String ACTION_ENTER_CAR_MODE = "android.app.action.ENTER_CAR_MODE";        /**     * Broadcast sent when the device's UI has switch away from car mode back     * to normal mode.  Typically used by a car mode app, to dismiss itself     * when the user exits car mode.     */    public static String ACTION_EXIT_CAR_MODE = "android.app.action.EXIT_CAR_MODE";        /**     * Broadcast sent when the device's UI has switched to desk mode,     * by being placed in a desk dock.  After     * sending the broadcast, the system will start the intent     * {@link android.content.Intent#ACTION_MAIN} with category     * {@link android.content.Intent#CATEGORY_DESK_DOCK}     * to display the desk UI, which typically what an application would     * implement to provide their own interface.  However, applications can     * also monitor this Intent in order to be informed of mode changes or     * prevent the normal desk UI from being displayed by setting the result     * of the broadcast to {@link Activity#RESULT_CANCELED}.     */    public static String ACTION_ENTER_DESK_MODE = "android.app.action.ENTER_DESK_MODE";        /**     * Broadcast sent when the device's UI has switched away from desk mode back     * to normal mode.  Typically used by a desk mode app, to dismiss itself     * when the user exits desk mode.     */    public static String ACTION_EXIT_DESK_MODE = "android.app.action.EXIT_DESK_MODE";        /** Constant for {@link #setNightMode(int)} and {@link #getNightMode()}:     * automatically switch night mode on and off based on the time.     */    public static final int MODE_NIGHT_AUTO = Configuration.UI_MODE_NIGHT_UNDEFINED >> 4;        /** Constant for {@link #setNightMode(int)} and {@link #getNightMode()}:     * never run in night mode.     */    public static final int MODE_NIGHT_NO = Configuration.UI_MODE_NIGHT_NO >> 4;        /** Constant for {@link #setNightMode(int)} and {@link #getNightMode()}:     * always run in night mode.     */    public static final int MODE_NIGHT_YES = Configuration.UI_MODE_NIGHT_YES >> 4;    private IUiModeManager mService;    /*package*/ UiModeManager() {        mService = IUiModeManager.Stub.asInterface(                ServiceManager.getService(Context.UI_MODE_SERVICE));    }    /**     * Flag for use with {@link #enableCarMode(int)}: go to the car     * home activity as part of the enable.  Enabling this way ensures     * a clean transition between the current activity (in non-car-mode) and     * the car home activity that will serve as home while in car mode.  This     * will switch to the car home activity even if we are already in car mode.     */    public static final int ENABLE_CAR_MODE_GO_CAR_HOME = 0x0001;        /**     * Force device into car mode, like it had been placed in the car dock.     * This will cause the device to switch to the car home UI as part of     * the mode switch.     * @param flags Must be 0.     */    public void enableCarMode(int flags) {        if (mService != null) {            try {                mService.enableCarMode(flags);            } catch (RemoteException e) {                Log.e(TAG, "disableCarMode: RemoteException", e);            }        }    }    /**     * Flag for use with {@link #disableCarMode(int)}: go to the normal     * home activity as part of the disable.  Disabling this way ensures     * a clean transition between the current activity (in car mode) and     * the original home activity (which was typically last running without     * being in car mode).     */    public static final int DISABLE_CAR_MODE_GO_HOME = 0x0001;        /**     * Turn off special mode if currently in car mode.     * @param flags May be 0 or {@link #DISABLE_CAR_MODE_GO_HOME}.     */    public void disableCarMode(int flags) {        if (mService != null) {            try {                mService.disableCarMode(flags);            } catch (RemoteException e) {                Log.e(TAG, "disableCarMode: RemoteException", e);            }        }    }    /**     * Return the current running mode type.  May be one of     * {@link Configuration#UI_MODE_TYPE_NORMAL Configuration.UI_MODE_TYPE_NORMAL},     * {@link Configuration#UI_MODE_TYPE_DESK Configuration.UI_MODE_TYPE_DESK}, or     * {@link Configuration#UI_MODE_TYPE_CAR Configuration.UI_MODE_TYPE_CAR},     */    public int getCurrentModeType() {        if (mService != null) {            try {                return mService.getCurrentModeType();            } catch (RemoteException e) {                Log.e(TAG, "getCurrentModeType: RemoteException", e);            }        }        return Configuration.UI_MODE_TYPE_NORMAL;    }    /**     * Sets the night mode.  Changes to the night mode are only effective when     * the car or desk mode is enabled on a device.     *     * <p>The mode can be one of:     * <ul>     *   <li><em>{@link #MODE_NIGHT_NO}<em> - sets the device into notnight     *       mode.</li>     *   <li><em>{@link #MODE_NIGHT_YES}</em> - sets the device into night mode.     *   </li>     *   <li><em>{@link #MODE_NIGHT_AUTO}</em> - automatic night/notnight switching     *       depending on the location and certain other sensors.</li>     * </ul>     */    public void setNightMode(int mode) {        if (mService != null) {            try {                mService.setNightMode(mode);            } catch (RemoteException e) {                Log.e(TAG, "setNightMode: RemoteException", e);            }        }    }    /**     * Returns the currently configured night mode.     *     * @return {@link #MODE_NIGHT_NO}, {@link #MODE_NIGHT_YES}, or     *  {@link #MODE_NIGHT_AUTO}.  When an error occurred -1 is returned.     */    public int getNightMode() {        if (mService != null) {            try {                return mService.getNightMode();            } catch (RemoteException e) {                Log.e(TAG, "getNightMode: RemoteException", e);            }        }        return -1;    }}