VolumeDialog音量控制自定义

VolumeDialog音量控制自定义

1 使用自定义 AlertDialog 实现

2 window?.setFlags 设置 dialog 的样式

3 window?.attributes 设置 dialog 的位置

4 返回键监听，兼容机型需要使用 setOnKeyListener

5 按一次音量键回调多次的问题，KeyEvent.action 事件分 KeyEvent.ACTION_UP 和 KeyEvent.ACTION_DOWN

6 音量加减需要获取系统音量 max 值来手动控制，不同手机 max 值域不同

示例代码如下：

import android.app.Activity
import android.content.Context
import android.content.res.Resources
import android.media.AudioManager
import android.os.Bundle
import android.os.Handler
import android.os.Looper
import android.util.Log
import android.util.TypedValue
import android.view.Gravity
import android.view.KeyEvent
import android.view.WindowManager
import android.widget.ProgressBar
import androidx.appcompat.app.AlertDialog

/**
 * 声音调整控件
 */
class VolumeDialog(activity: Activity) : AlertDialog(activity, R.style.VolumeDialog) {
    companion object {
        private const val TAG = "VolumeDialog"

        @JvmStatic
        fun show(activity: Activity) {
            activity.let {
                if (activity.isFinishing) return
                VolumeDialog(activity).show()
            }
        }
    }

    private val volumeAudioManager = context.getSystemService(Context.AUDIO_SERVICE) as AudioManager
    private var volume = volumeAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC)
    private val maxVolume = volumeAudioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC)
    private val step = (maxVolume / 10).coerceAtLeast(1)
    private val delayMillis = 1500L

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.dialog_volume_progress)

        //实现Dialog区域外部事件可以传给Activity
        // FLAG_NOT_TOUCH_MODAL作用：即使该window可获得焦点情况下，仍把该window之外的任何event发送到该window之后的其他window
        window?.setFlags(
            WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL,
            WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
        )

        // FLAG_WATCH_OUTSIDE_TOUCH作用：如果点击事件发生在window之外，就会收到一个特殊的MotionEvent，为ACTION_OUTSIDE
        window?.setFlags(
            WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH,
            WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
        )

        // 顶部显示
        //        window?.setGravity(Gravity.TOP)
        val attrs = window?.attributes
        attrs?.apply {
            gravity = Gravity.TOP
            height = WindowManager.LayoutParams.WRAP_CONTENT
            width = WindowManager.LayoutParams.MATCH_PARENT
            y = TypedValue.applyDimension(
                TypedValue.COMPLEX_UNIT_DIP,
                35f,
                Resources.getSystem().displayMetrics
            ).toInt()
        }
        Log.d(TAG, "onCreate() called with: attrs = $attrs")
        window?.attributes = attrs
        // 按空白处不能取消
        setCanceledOnTouchOutside(false)
        // 初始化界面控件
        initView()
    }

    private var volumeProgressView: VolumeProgressView? = null
    private var progressBar: ProgressBar? = null

    private val _handler = Handler(Looper.getMainLooper())
    private val r = Runnable {
        try {
            dismiss()
        } catch (e: Exception) {
            // sometimes happens windows token error.
            e.printStackTrace()
        }
    }

    override fun dismiss() {
        _handler.removeCallbacks(r)
        super.dismiss()
    }

    private fun initView() {
        Log.d(TAG, "initView: ")
        volumeProgressView = findViewById(R.id.vpv_volume)
        progressBar = findViewById(R.id.pb_volume)

        refreshProgress(volume * 1f / maxVolume)

        // 解决不同机型版本兼容问题，onKeyDown 可能被拦截
        setOnKeyListener { _, keyCode, event ->
          Log.d(TAG, "setOnKeyListener: keyCode = $keyCode, event = $event")
          if (keyCode == KeyEvent.KEYCODE_VOLUME_UP || keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
              handleKeyEvent(keyCode, event)
              true
          } else {
              false
          }
         }
    }

    private fun refreshProgress(volumePercent: Float) {
        _handler.removeCallbacks(r)
        volumeProgressView?.setProgress(volumePercent)
        progressBar?.progress = (volumePercent * 1000).toInt()
        _handler.postDelayed(r, delayMillis)
    }


    private fun handleKeyEvent(keyCode: Int, event: KeyEvent): Boolean {
        Log.d(TAG, "handleKeyEvent: volume = $volume, maxVolume = $maxVolume, step = $step")
        if ((keyCode != KeyEvent.KEYCODE_VOLUME_UP && keyCode != KeyEvent.KEYCODE_VOLUME_DOWN) || event.action != KeyEvent.ACTION_DOWN) return false
        volume = if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) { // up
            if (volume == maxVolume) return true
            maxVolume.coerceAtMost(volume + step)
        } else { // down
            if (volume == 0) return true
            0.coerceAtLeast(volume - step)
        }
        val volumePercent = volume * 1f / maxVolume
        refreshProgress(volumePercent)

        // 变更声音
        volumeAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, volume, 0)
        Log.d(TAG, "handleKeyEvent: AudioManager set volume = $volume done.")

        return true
    }

    /**
     * 返回事件，仅拦截音量控制事件
     */
    override fun onKeyDown(keyCode: Int, event: KeyEvent): Boolean {
        Log.d(TAG, "onKeyDown() called with: keyCode = $keyCode, event = $event")
        return if (keyCode == KeyEvent.KEYCODE_VOLUME_UP || keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
            handleKeyEvent(keyCode, event)
            return true
        } else {
            super.onKeyDown(keyCode, event)
        }
    }
}

自定义Dialog的Style

 <style name="VolumeDialog" parent="android:style/Theme.Dialog">
    <!--背景颜色及和透明程度-->
    <item name="android:windowBackground">@android:color/transparent</item>
    <!--是否去除标题 -->
    <item name="android:windowNoTitle">true</item>
    <!--是否去除边框-->
    <item name="android:windowFrame">@null</item>
    <!--是否浮现在activity之上-->
    <item name="android:windowIsFloating">true</item>
    <!--是否模糊-->
    <item name="android:backgroundDimEnabled">false</item>
</style>