改变屏幕Brightness(亮度)

http://www.eoeandroid.com/forum-redirect-tid-66701-goto-lastpost.html#lastpost

看到论坛上有很多问亮度的问题(只能改变当前的Activity的问题，这个程序可以改变整个System的亮度)希望可以给朋友们带来帮助.

package com.jimmy;import android.app.Activity;import android.os.Bundle;import android.provider.Settings;import android.view.Window;import android.view.WindowManager;import android.widget.SeekBar;import android.widget.TextView;import android.widget.SeekBar.OnSeekBarChangeListener;public class MyActivity extends Activity {        /** Called when the activity is first created. */        TextView textView;        @Override        public void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                setContentView(R.layout.main);                textView = (TextView) findViewById(R.id.MyTextView);                updateToggles();        }        private void updateToggles() {                // TODO Auto-generated method stub                SeekBar seekBar = (SeekBar) findViewById(R.id.MySeekBar);                seekBar.setProgress((int) (android.provider.Settings.System.getInt(                                getContentResolver(),                                android.provider.Settings.System.SCREEN_BRIGHTNESS, 255) ));                seekBar.setOnSeekBarChangeListener(seekListener);        }        private OnSeekBarChangeListener seekListener = new OnSeekBarChangeListener() {                public void onProgressChanged(SeekBar seekBar, int progress,                                boolean fromUser) {                        if (fromUser) {                                Integer tmpInt = seekBar.getProgress();                                System.out.println(tmpInt);                                // 51 (seek scale) * 5 = 255 (max brightness)                                // Old way                                android.provider.Settings.System.putInt(getContentResolver(),                                                android.provider.Settings.System.SCREEN_BRIGHTNESS,                                                tmpInt); // 0-255                                tmpInt = Settings.System.getInt(getContentResolver(),                                                Settings.System.SCREEN_BRIGHTNESS, -1);                                // Cupcake way..... sucks                                WindowManager.LayoutParams lp = getWindow().getAttributes();                                // lp.screenBrightness = 1.0f;                                // Float tmpFloat = (float)tmpInt / 255;                                if (0<= tmpInt && tmpInt <= 255) {                                        lp.screenBrightness = tmpInt;                                }                                                                                                getWindow().setAttributes(lp);                        }                }                @Override                public void onStartTrackingTouch(SeekBar seekBar) {                        // TODO Auto-generated method stub                        // put awesomeness here                }                @Override                public void onStopTrackingTouch(SeekBar seekBar) {                        // TODO Auto-generated method stub                        // and here too                }        };}

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"        android:orientation="vertical" android:layout_width="fill_parent"        android:layout_height="fill_parent" android:background="@color/white">        <TextView android:id="@+id/MyTextView"                android:layout_width="fill_parent" android:layout_height="wrap_content"                android:text="亮度是:" />                        <SeekBar                android:layout_gravity="center_horizontal"                android:id="@+id/MySeekBar"                android:paddingLeft="5.0dip"                android:paddingRight="5.0dip"                android:layout_width="fill_parent"                android:layout_height="150dip"                android:layout_marginTop="10.0dip"                android:layout_marginBottom="10.0dip"                android:max="255"                >        </SeekBar></LinearLayout>

权限:

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"        package="com.jimmy" android:versionCode="1" android:versionName="1.0">        <application android:icon="@drawable/icon" android:label="@string/app_name">                <activity android:name=".MyActivity" android:label="@string/app_name">                        <intent-filter>                                <action android:name="android.intent.action.MAIN" />                                <category android:name="android.intent.category.LAUNCHER" />                        </intent-filter>                </activity>        </application>        <uses-sdk android:minSdkVersion="5" />        <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>        <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>        <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>        <uses-permission android:name="android.permission.BATTERY_STATS"></uses-permission>        <uses-permission android:name="android.permission.DEVICE_POWER"></uses-permission>        <uses-permission android:name="android.permission.SET_DEBUG_APP"></uses-permission>        <uses-permission android:name="android.permission.CHANGE_CONFIGURATION"></uses-permission>        <uses-permission android:name="android.permission.WRITE_SETTINGS"></uses-permission>        <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission></manifest> 

1 楼 NevoCao 2011-11-17 哥们，按照你这样写的，不能调节亮度咋回事？调到最左端能黑屏，其他的无反应