Description:
This example shows how you can change brightness settings on device through coding.
Algorithm:
1.) Create a new project by File-> New -> Android Project name it BrightnessExample.
2.) Set write permission to devic’s settings in manifest file. Write following into your manifest file:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="10" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:label="@string/app_name"
android:name=".BrightnessExample" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<uses-permission android:name="android.permission.WRITE_SETTINGS"/>
</manifest>
3.) Write following into your main.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Set BackLight of the App" />
<SeekBar
android:id="@+id/backlightcontrol"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margin="10px"
android:max="100"
android:progress="50" />
<TextView
android:id="@+id/backlightsetting"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="0.50" />
<Button
android:id="@+id/updatesystemsetting"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Update Settings.System.SCREEN_BRIGHTNESS" />
</LinearLayout>
4.) Run for output.
Steps:
1.) Create a project named BrightnessExample and set the information as stated in the image.
Build Target: Android 2.3.3
Application Name: BrightnessExample
Package Name: com.example
Activity Name: BrightnessExample
Min SDK Version: 10
2.) Open BrightnessExample.java file and write following code there:
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.TextView;
public class BrightnessExample extends Activity {
/** Called when the activity is first created. */
float BackLightValue = 0.5f; //dummy default value
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
SeekBar BackLightControl = (SeekBar)findViewById(R.id.backlightcontrol);
final TextView BackLightSetting = (TextView)findViewById(R.id.backlightsetting);
Button UpdateSystemSetting = (Button)findViewById(R.id.updatesystemsetting);
UpdateSystemSetting.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
int SysBackLightValue = (int)(BackLightValue * 255);
android.provider.Settings.System.putInt(getContentResolver(),
android.provider.Settings.System.SCREEN_BRIGHTNESS,
SysBackLightValue);
}});
BackLightControl.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener(){
@Override
public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) {
// TODO Auto-generated method stub
BackLightValue = (float)arg1/100;
BackLightSetting.setText(String.valueOf(BackLightValue));
WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
layoutParams.screenBrightness = BackLightValue;
getWindow().setAttributes(layoutParams);
}
@Override
public void onStartTrackingTouch(SeekBar arg0) {
}
@Override
public void onStopTrackingTouch(SeekBar arg0) {
}});
}
}
3.) Compile and build the project.
Output
No related posts.
