Android 一体机研发之修改系统设置————屏幕亮度

Android 一体机研发之修改系统设置————声音

Android 一体机研发之修改系统设置————自动锁屏

前言

最近工作略微有点儿空闲，抽空给大家总结一下：近期一直搞得一体机app研发，适用于医疗渠道。

一体机找工厂定制了一下板子和系统，找他们fw后期app会以apk的形式封装到系统中，当然了开机logo也会封装进去。

在这版一体机，有一个可以更改系统设置的功能版块，记得之前总结过Android 调用系统设置，有兴趣的可以去看一下；这一篇将把部分功能做一个细分化讲解。

但是在调用系统设置的时候，有些系统功能让用户一看就和手机一样的功能，并且有些功能是我们不需要的，这里就需要我们自己去实现修改系统权限的功能。

接下来，会给大家出几篇一体机研发之修改系统设置系列文章，欢迎我们共同学习进步！

屏幕亮度

修改系统屏幕亮度这种操作还是挺常见的，一般在多媒体开发中多少会涉及到。

从上图中虽然很难看出效果展示，但是大概都能猜到功能的具体实现，就是通过seekBar来控制亮度的百分比。

如果想实现修改屏幕亮度功能，这里涉及了一个高级隐私权限，需要用户在app设置页面手动授权。

设计思路

1. AndroidManifest设置权限;

2. 获取系统屏幕亮度；

3. 修改系统Settings 中屏幕亮度（注册监听屏幕亮度变化），影响所有页面和App；

   3.1 判断权限

   3.2 有则修改屏幕亮度

   3.3 无则引导用户授权

具体实现

AndroidManifest设置权限

获取系统屏幕亮度

• Java

	/*** 获取app屏幕亮度** @param activity* @return*/public static int getScreenBrightness(Activity activity) {try {return Settings.System.getInt(activity.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS);} catch (Settings.SettingNotFoundException e) {e.printStackTrace();}return 0;}

• Kotlin

	/*** 获取系统屏幕亮度(0-255)*/private fun getScreenBrightness(): Int {try {return Settings.System.getInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS)} catch (e: SettingNotFoundException) {e.printStackTrace()}return 0}

修改系统Settings 中屏幕亮度，影响所有页面和App

注册监听 系统屏幕亮度变化

• Java

	private void registerContentObserver() {ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {contentResolver.registerContentObserver(Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS),true,mBrightnessObserver);}}

• Kotlin

	private fun registerContentObserver() {this.contentResolver?.registerContentObserver(Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS),true,mBrightnessObserver)}

监听系统亮度变化

• Java

	private ContentObserver mBrightnessObserver = new ContentObserver(new Handler()) {@Overridepublic void onChange(boolean selfChange) {super.onChange(selfChange);ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {mScreenBrightness = getScreenBrightness(BrightActivity.this);Log.e("监听亮度 >>>", "init: " + mScreenBrightness);updateNum(mScreenBrightness);setWindowBrightness(mScreenBrightness);}}};

• Kotlin

	private val mBrightnessObserver = object : ContentObserver(Handler(Looper.getMainLooper())) {override fun onChange(selfChange: Boolean) {super.onChange(selfChange)try {this@BrightnessActivity.contentResolver?.let {mScreenBrightness = Settings.System.getInt(it, Settings.System.SCREEN_BRIGHTNESS)updateNum(mScreenBrightness)setWindowBrightness(mScreenBrightness)}} catch (e: SettingNotFoundException) {e.printStackTrace()}}}

注销监听

• Java

	@Overrideprotected void onDestroy() {super.onDestroy();ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {contentResolver.unregisterContentObserver((ContentObserver) mBrightnessObserver);}}

• Kotlin

	override fun onDestroy() {super.onDestroy()//注销监听this.contentResolver?.unregisterContentObserver(mBrightnessObserver)}

通过seekBar修改系统Settings 中屏幕亮度

• Java

	brightBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {@RequiresApi(api = Build.VERSION_CODES.M)@Overridepublic void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {Log.e("动态屏幕亮度 >>>", "onProgressChanged: " + progress);mScreenBrightness = progress * ratio;if (Settings.System.canWrite(BrightActivity.this)) {setScreenBrightness(mScreenBrightness);updateNum(mScreenBrightness);} else {Toast.makeText(BrightActivity.this, "没有修改权限", Toast.LENGTH_SHORT).show();// 打开允许修改Setting 权限的界面Intent intent = new Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS, Uri.parse("package:"+ getPackageName()));startActivityForResult(intent,mRequestCode);}}@Overridepublic void onStartTrackingTouch(SeekBar seekBar) {}@Overridepublic void onStopTrackingTouch(SeekBar seekBar) {}});

• Kotlin

	seekBar.setOnSeekBarChangeListener(object : SeekBar.OnSeekBarChangeListener {override fun onProgressChanged(seekBar: SeekBar?, progress: Int, fromUser: Boolean) {Log.i("onProgressChanged----", "" + progress)mScreenBrightness = progress * ratio//判断是否有修改系统设置权限if (Settings.System.canWrite(this@BrightnessActivity)) {setScreenBrightness(mScreenBrightness)updateNum(mScreenBrightness)} else {Toast.makeText(this@BrightnessActivity, "没有修改权限", Toast.LENGTH_SHORT).show()// 打开允许修改系统设置权限的页面val intent = Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS, Uri.parse("package:$packageName"))startActivityForResult(intent, mRequestCode)}}override fun onStartTrackingTouch(seekBar: SeekBar?) {}override fun onStopTrackingTouch(seekBar: SeekBar?) {}})

用户已授权，设置屏幕亮度

• Java

 	/*** 设置系统屏幕亮度，影响所有页面和app* 注意：这种方式是需要手动权限的（android.permission.WRITE_SETTINGS）*/private final void setScreenBrightness(int brightness) {//先检测调节模式setScreenManualMode();//再设置Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, brightness);}private final void setScreenManualMode() {try {//获取当前系统亮度调节模式int mode = Settings.System.getInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS_MODE);//如果是自动，则改为手动if (mode == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC) {Settings.System.putInt(getContentResolver(),Settings.System.SCREEN_BRIGHTNESS_MODE,Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);}} catch (Settings.SettingNotFoundException var2) {var2.printStackTrace();}}

• Kotlin

 	/*** 设置系统屏幕亮度，影响所有页面和app* 注意：这种方式是需要手动权限的（android.permission.WRITE_SETTINGS）*/private fun setScreenBrightness(brightness: Int) {try {//先检测调节模式setScreenManualMode()//再设置Settings.System.putInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS, brightness)} catch (e: SettingNotFoundException) {e.printStackTrace()}}/*** 设置系统亮度调节模式(SCREEN_BRIGHTNESS_MODE)* SCREEN_BRIGHTNESS_MODE_MANUAL 手动调节* SCREEN_BRIGHTNESS_MODE_AUTOMATIC 自动调节*/private fun setScreenManualMode() {try {//获取当前系统亮度调节模式val mode = Settings.System.getInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS_MODE)//如果是自动，则改为手动if (mode == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC) {Settings.System.putInt(this.contentResolver,Settings.System.SCREEN_BRIGHTNESS_MODE,Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL)}} catch (e: SettingNotFoundException) {e.printStackTrace()}}

监听系统按键

	//监听系统按键@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {switch (keyCode) {case KeyEvent.KEYCODE_VOLUME_DOWN:if (mScreenBrightness > ratio) {mScreenBrightness -= ratio;} else {mScreenBrightness = 1;}Log.e("Down >>>", "onKeyDown: " + mScreenBrightness);setWindowBrightness(mScreenBrightness);updateNum(mScreenBrightness);return true;case KeyEvent.KEYCODE_VOLUME_UP:if (mScreenBrightness < (255 - ratio)) {mScreenBrightness += ratio;} else {mScreenBrightness = 255;}Log.e("Up >>>", "onKeyDown: " + mScreenBrightness);setWindowBrightness(mScreenBrightness);updateNum(mScreenBrightness);return true;/* case KeyEvent.KEYCODE_VOLUME_MUTE:return true;*/}return super.onKeyDown(keyCode, event);}

完整操作

• Java

/*** @author 拉莫帅* @date 2023/2/8* @address* @Desc 修改系统亮度*/
public class BrightActivity extends Activity {/*** 非系统签名应用，引导用户手动授权修改Settings 权限**/private int mRequestCode = 1;private SeekBar brightBar;//当前屏幕亮度private int mScreenBrightness = 0;//每次加减的比例private int ratio = 25;private ContentObserver mBrightnessObserver = new ContentObserver(new Handler()) {@Overridepublic void onChange(boolean selfChange) {super.onChange(selfChange);ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {mScreenBrightness = getScreenBrightness(BrightActivity.this);Log.e("监听亮度 >>>", "init: " + mScreenBrightness);updateNum(mScreenBrightness);setWindowBrightness(mScreenBrightness);}}};@RequiresApi(api = Build.VERSION_CODES.M)@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_bright);init();registerContentObserver();setListener();}private void init() {brightBar = findViewById(R.id.brightBar);ImageView back = findViewById(R.id.back);TextView title = findViewById(R.id.title);title.setText("亮度");//获取当前亮度mScreenBrightness = getScreenBrightness(BrightActivity.this);Log.e("当前亮度 >>>", "init: " + mScreenBrightness);updateNum(mScreenBrightness);back.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {finish();}});}private void registerContentObserver() {ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {contentResolver.registerContentObserver(Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS),true,mBrightnessObserver);}}@Overrideprotected void onDestroy() {super.onDestroy();ContentResolver contentResolver = getContentResolver();if (contentResolver != null) {contentResolver.unregisterContentObserver((ContentObserver) mBrightnessObserver);}}private void setListener() {brightBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {@RequiresApi(api = Build.VERSION_CODES.M)@Overridepublic void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {Log.e("动态屏幕亮度 >>>", "onProgressChanged: " + progress);mScreenBrightness = progress * ratio;if (Settings.System.canWrite(BrightActivity.this)) {setScreenBrightness(mScreenBrightness);updateNum(mScreenBrightness);} else {Toast.makeText(BrightActivity.this, "没有修改权限", Toast.LENGTH_SHORT).show();// 打开允许修改Setting 权限的界面Intent intent = new Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS, Uri.parse("package:"+ getPackageName()));startActivityForResult(intent,mRequestCode);}}@Overridepublic void onStartTrackingTouch(SeekBar seekBar) {}@Overridepublic void onStopTrackingTouch(SeekBar seekBar) {}});}@RequiresApi(api = Build.VERSION_CODES.M)@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);if (requestCode == mRequestCode) {if (Settings.System.canWrite((Context) BrightActivity.this)) {setScreenBrightness(mScreenBrightness);updateNum(mScreenBrightness);} else {Toast.makeText((Context) this, "您已拒绝修系统Setting的屏幕亮度权限", Toast.LENGTH_SHORT).show();}}}/*** 获取app屏幕亮度** @param activity* @return*/public static int getScreenBrightness(Activity activity) {try {return Settings.System.getInt(activity.getContentResolver(), Settings.System.SCREEN_BRIGHTNESS);} catch (Settings.SettingNotFoundException e) {e.printStackTrace();}return 0;}/*** 更新页面显示** @param mScreenBrightness*/private final void updateNum(int mScreenBrightness) {//四舍五入int i = (int) Math.floor(mScreenBrightness / ratio);brightBar.setProgress(i);}/*** 设置系统屏幕亮度，影响所有页面和app* 注意：这种方式是需要手动权限的（android.permission.WRITE_SETTINGS）*/private final void setScreenBrightness(int brightness) {//先检测调节模式setScreenManualMode();//再设置Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, brightness);}private final void setScreenManualMode() {try {//获取当前系统亮度调节模式int mode = Settings.System.getInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS_MODE);//如果是自动，则改为手动if (mode == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC) {Settings.System.putInt(getContentResolver(),Settings.System.SCREEN_BRIGHTNESS_MODE,Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);}} catch (Settings.SettingNotFoundException var2) {var2.printStackTrace();}}/*** 设置当前应用屏幕亮度，只当前有效*/private final void setWindowBrightness(int brightness) {Window window = this.getWindow();WindowManager.LayoutParams lp = window.getAttributes();lp.screenBrightness = (float) brightness / 255.0F;window.setAttributes(lp);}//监听系统按键@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {switch (keyCode) {case KeyEvent.KEYCODE_VOLUME_DOWN:if (mScreenBrightness > ratio) {mScreenBrightness -= ratio;} else {mScreenBrightness = 1;}Log.e("Down >>>", "onKeyDown: " + mScreenBrightness);setWindowBrightness(mScreenBrightness);updateNum(mScreenBrightness);return true;case KeyEvent.KEYCODE_VOLUME_UP:if (mScreenBrightness < (255 - ratio)) {mScreenBrightness += ratio;} else {mScreenBrightness = 255;}Log.e("Up >>>", "onKeyDown: " + mScreenBrightness);setWindowBrightness(mScreenBrightness);updateNum(mScreenBrightness);return true;/* case KeyEvent.KEYCODE_VOLUME_MUTE:return true;*/}return super.onKeyDown(keyCode, event);}
}

• Kotlin

class BrightnessActivity : AppCompatActivity() {//当前屏幕亮度private var mScreenBrightness: Int = 0//每次加减的比例private var ratio: Int = 25private var mRequestCode = 1override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_brightness)init()registerContentObserver()setListener()}private fun init() {mScreenBrightness = getScreenBrightness()updateNum(mScreenBrightness)}/*** 注册监听 系统屏幕亮度变化*/private fun registerContentObserver() {this.contentResolver?.registerContentObserver(Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS),true,mBrightnessObserver)}/*** 监听系统亮度变化*/private val mBrightnessObserver = object : ContentObserver(Handler(Looper.getMainLooper())) {override fun onChange(selfChange: Boolean) {super.onChange(selfChange)try {this@BrightnessActivity.contentResolver?.let {mScreenBrightness = Settings.System.getInt(it, Settings.System.SCREEN_BRIGHTNESS)updateNum(mScreenBrightness)setWindowBrightness(mScreenBrightness)}} catch (e: SettingNotFoundException) {e.printStackTrace()}}}override fun onDestroy() {super.onDestroy()//注销监听this.contentResolver?.unregisterContentObserver(mBrightnessObserver)}private fun setListener() {seekBar.setOnSeekBarChangeListener(object : SeekBar.OnSeekBarChangeListener {override fun onProgressChanged(seekBar: SeekBar?, progress: Int, fromUser: Boolean) {Log.i("onProgressChanged----", "" + progress)mScreenBrightness = progress * ratio//判断是否有修改系统设置权限if (Settings.System.canWrite(this@BrightnessActivity)) {setScreenBrightness(mScreenBrightness)updateNum(mScreenBrightness)} else {Toast.makeText(this@BrightnessActivity, "没有修改权限", Toast.LENGTH_SHORT).show()// 打开允许修改系统设置权限的页面val intent = Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS, Uri.parse("package:$packageName"))startActivityForResult(intent, mRequestCode)}}override fun onStartTrackingTouch(seekBar: SeekBar?) {}override fun onStopTrackingTouch(seekBar: SeekBar?) {}})}/*** 处理返回结果*/override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {super.onActivityResult(requestCode, resultCode, data)if (requestCode == mRequestCode) {if (Settings.System.canWrite(this@BrightnessActivity)) {setScreenBrightness(mScreenBrightness)updateNum(mScreenBrightness)} else {Toast.makeText(this@BrightnessActivity, "拒绝了权限", Toast.LENGTH_SHORT).show()}}}/*** 更新页面显示*/private fun updateNum(mScreenBrightness: Int) {//转float 取四舍五入val i: Int = (mScreenBrightness / (ratio.toFloat())).roundToInt()tv_brightness.text = i.toString()seekBar.progress = i}/*** 获取系统屏幕亮度(0-255)*/private fun getScreenBrightness(): Int {try {return Settings.System.getInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS)} catch (e: SettingNotFoundException) {e.printStackTrace()}return 0}/*** 设置系统屏幕亮度，影响所有页面和app* 注意：这种方式是需要手动权限的（android.permission.WRITE_SETTINGS）*/private fun setScreenBrightness(brightness: Int) {try {//先检测调节模式setScreenManualMode()//再设置Settings.System.putInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS, brightness)} catch (e: SettingNotFoundException) {e.printStackTrace()}}/*** 设置系统亮度调节模式(SCREEN_BRIGHTNESS_MODE)* SCREEN_BRIGHTNESS_MODE_MANUAL 手动调节* SCREEN_BRIGHTNESS_MODE_AUTOMATIC 自动调节*/private fun setScreenManualMode() {try {//获取当前系统亮度调节模式val mode = Settings.System.getInt(this.contentResolver, Settings.System.SCREEN_BRIGHTNESS_MODE)//如果是自动，则改为手动if (mode == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC) {Settings.System.putInt(this.contentResolver,Settings.System.SCREEN_BRIGHTNESS_MODE,Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL)}} catch (e: SettingNotFoundException) {e.printStackTrace()}}/*** 设置当前应用屏幕亮度，只当前有效*/private fun setWindowBrightness(brightness: Int) {val window = windowval lp = window.attributeslp.screenBrightness = brightness / 255.0fwindow.attributes = lp}
}

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