android headphone volume

Android Bottom -up headphone Plug and audio channel switching instanceBecause headphones are used as separate headsets, the events are reported separately. The detection of headphone jacks on the Android system layer is based on /sys/class/switch/h2w/state values (in 4.4.4_r2 For example in Wiredaccessorymanager.java).

Android Potential Development headphone plug connection to audio channel switch exampleBecause you are using headphones with a separate headset, you have to escalate the event separately. The detection of headphone jacks on the Android system layer is inferred based on The value of the/sys/class/switch/h2w/state (in 4

To detect headphone insertion and removal under Android, you need to create a broadcastreceiver, used to listen for "Android.intent.action.HEADSET_PLUG" broadcasts. implementation steps:1. Create a broadcastreceiver subclass and override the OnReceive () method,in this method, the processing logic after receiving the broadcast is written;2. Create an activity class that uses Registerreceiver () in the OnCre

Android game background music audio volume control, android volume control Game sound effects are the music we use to play games. This is also a must-have for every game. However, if the background music you play is interrupted, we can use getCurrentPosition () this method is used to determine the audio playback offset

Android volume key monitoring and android Volume monitoring Conclusion: The following two methods can be used to obtain the volume key. During the test, we found that When KeyEvent. KEYCODE_VOLUME_UP is held down all the time, Samsung's tablet counts to 200, and this event i

1,:2, Code:Mainactivity.java PackageCom.hero.zhaoq.seekbarchangeddemo;ImportAndroid.content.BroadcastReceiver;ImportAndroid.content.Context;ImportAndroid.content.Intent;ImportAndroid.content.IntentFilter;ImportAndroid.database.ContentObserver;ImportAndroid.media.AudioManager;ImportAndroid.os.Handler;Importandroid.support.v7.app.AppCompatActivity;ImportAndroid.os.Bundle;ImportAndroid.util.Log;ImportAndroid.widget.SeekBar;/** * Android implements Seekba

; Normally in the audio and video interface to adjust the volume of the stream is Stream_music, back to luncher adjust is stream_voice_call, but this switch a little delay streamoverride.sdelayms, resulting in the exit tone, After the video interface is adjusted immediately, the change is still the size of the Stream_music:You can modify the/frameworks/base/media/java/android/media/audioservice.java file /*

Android android source code case when adding the volume plus/minus button in the navigation bar, Android android Some Android devices do not have a volume adjustment button for the enti

Android sliding scroll bar to adjust the volume, android scroll bar Use scroll bar sliding to control the volume: Definition: 1 private SeekBar mseekBarvolume； The following code is used: 1 // adjust the volume -- begin ------------------------- 2 //

Some Android devices do not have an entity's volume adjustment button, or from the point of view of protecting the body keys, you need to add a volume plus minus adjustment button to the virtual keys in the navigation bar.Here I recommend the more good Android source fragment website: http://code.662p.com/list/173_1.ht

In the past two days, due to a customer's requirement, the volume key on the status bar of the MID portrait screen is removed. So I tried to modify it, succeeded, and shared my experience. Take a look at the modified one, as shown below. Horizontal screen: there is a volume plus or minus key Portrait screen: The volume plus or minus key is removed Then let's

Learn Lei Feng, a good example, the next tutorial in this series, will be through unity to achieve some of the common features of the Android side,It is important not to refer to the jar package or the AAR package in the Asset/plugins/android directory.1 usingSystem.Collections;2 usingSystem.Collections.Generic;3 usingUnityengine;4 5 Public classVolume:monobehaviour {6 7 8 Private Const stringCurrentvo

the files in that directory are stored in the system memory.I learned from this chapter that, regardless of which version of the Linux kernel, the methods and procedures for developing Linux drivers are basically the same, As long as you have mastered the driver development of a Linux kernel version (recommended using the Linux2.6 or linux3.x kernel version), other Linux kernel versions are easy to master.GUN C is also a must-know technology for learning Linux drivers. GUN c is an extension to

Android deep exploration and HAL-driven development (Volume 1)-Chapter 7, android-driven developmentRelationship between applications, libraries, kernels, and drivers From top to bottom, a software system can be divided into applications, libraries, operating systems (kernels), and drivers. Developers can focus on what they are familiar with. For adjacent layers,

Android deep exploration and HAL-driven development (Volume 1)-Chapter 8: android-driven developmentBuzzer type and working principle The buzzer also becomes PWM (Pulse Width Modulation). The basic principle is to control the opening and stopping of the buzzer through the pulse. It is a very effective technology that uses the digital output of a microcontroller

(int quality) Set video quality, Low, medium, and High (Mediaplayer.videoquality_low, Mediaplayer.videoquality_medium, Mediaplayer.videoquality_high), The default is low (most fluid). 2.11 public void Setsubshown (Boolean shown) Set whether captions are displayed 2.12 public void Setaudiotrack (int audioindex) Set the audio track, which must be a getaudiotrackmap (String) return value. 2.13 public void SetVolume (float leftvolume, float rightvolume) Set stereo sound

The example in this article describes how Android uses Audiomanager to modify the volume of the system. Share to everyone for your reference, specific as follows: Here are a few audiomanager ways to adjust the volume. The first is to get the Audiomanager instance: Audiomanager am= (Audiomanager) Getsystemservice (Context.audio_service); There are

Main. xml layout File Android: orientation = "vertical" android: layout_width = "fill_parent"Android: layout_height = "fill_parent">Android: layout_width = "fill_parent"Android: layout_height = "wrap_content"Android: text = "playi

I am often asked how to calculate the volume during recording. The iOS platform has APIs that can be called directly, but there is no good method on the Android platform, so we have to calculate it by ourselves. The demand for volume calculation is because many applications want to achieve some animation effects based on the

Android. media. AudioManager contains the cross-process AIDL call encapsulation for android. media. AudioService.Normal handling process:1. To adjust the volume, AudioManager indirectly calls AudioService. adjustStreamVolume to complete logical processing;2. AudioService calls VolumePanel to draw the volume adjustment