Android VideoView总结

文章目录

[Android VideoView总结](#Android VideoView总结)
- 概述
- 实现
- - FullVideoView
  - 代码

Android VideoView总结

概述

VideoView 是 Android 原生轻量级视频播放控件，基于系统 MediaPlayer 封装，自动完成初始化、渲染、状态监听、资源回收，无需底层适配，是原生轻量视频播放最优方案。

实现

FullVideoView

VideoView 在 measure 阶段有个"自动等比修正"逻辑：例如：当宽高都是固定值（match_parent + 200dp）时，它会悄悄把自身尺寸改成和视频原始比例一致------比如 16:9 视频在 200dp 高的横条里，实际宽度会被算成 200dp × 16/9，导致左右多出一截黑底，看起来就是"视频没铺满"。

就算你设了裁剪模式，它也只是在缩放后的 view 尺寸内有效，view 本身先缩了，自然铺不满。

kotlin 复制代码

class FillVideoView @JvmOverloads constructor(
    context: Context,
    attrs: AttributeSet? = null,
    defStyleAttr: Int = 0
) : VideoView(context, attrs, defStyleAttr) {

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        val width = MeasureSpec.getSize(widthMeasureSpec)
        val height = MeasureSpec.getSize(heightMeasureSpec)
        // 始终用布局给定的宽高，不做 VideoView 默认的等比缩放修正
        setMeasuredDimension(width, height)
    }
}

代码

dart 复制代码

class MainActivity : AppCompatActivity() {
    private lateinit var videoView: FillVideoView
    private lateinit var tvProgress: TextView
    private lateinit var loadingView: ProgressBar
    private lateinit var tvBuffering: TextView
    private lateinit var btnStop: Button
    private lateinit var btnStartPause: Button
    private lateinit var btnVolumeUp: Button
    private lateinit var btnVolumeDown: Button
    private lateinit var btnVolumeMax: Button
    private lateinit var btnVolumeMute: Button

    private val audioManager by lazy { getSystemService(AUDIO_SERVICE) as android.media.AudioManager }
    private val handler = Handler(Looper.getMainLooper())
    private lateinit var progressRunnable: Runnable

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initView()
        initVideoView()
        initProgressListener()
    }

    private fun initView() {
        loadingView = findViewById(R.id.loading_view)
        videoView = findViewById(R.id.video_view)
        tvProgress = findViewById(R.id.tv_progress)
        tvBuffering = findViewById(R.id.tv_buffering)
        btnStartPause = findViewById(R.id.btn_start_pause)
        btnStop = findViewById(R.id.btn_stop)
        btnVolumeUp = findViewById(R.id.btn_volume_up)
        btnVolumeDown = findViewById(R.id.btn_volume_down)
        btnVolumeMax = findViewById(R.id.btn_volume_max)
        btnVolumeMute = findViewById(R.id.btn_volume_mute)

        btnStartPause.setOnClickListener {
            if (videoView.isPlaying) {
                // 暂停操作
                pauseVideo()
            } else {
                // 播放操作
                playVideo()
            }
        }
        btnStop.setOnClickListener {
            stopVideo()
        }
        btnVolumeUp.setOnClickListener { volumeUp() }
        btnVolumeDown.setOnClickListener { volumeDown() }
        btnVolumeMax.setOnClickListener { volumeMax() }
        btnVolumeMute.setOnClickListener { volumeMute() }
    }

    /**
     * 设置url
     */
    private fun setVideoUrl() {
        val videoUrl =
            "https://stream7.iqilu.com/10339/upload_transcode/202002/09/20200209104902N3v5Vpxuvb.mp4"
        videoView.setVideoURI(videoUrl.toUri())
    }

    /**
     * 播放视频
     */
    private fun playVideo() {
        btnStartPause.text = "暂停"
        videoView.start()
    }

    /**
     * 暂停
     */
    private fun pauseVideo() {
        btnStartPause.text = "播放"
        videoView.pause()
    }

    /**
     * 停止
     */
    private fun stopVideo() {
        videoView.stopPlayback()
        btnStartPause.text = "播放"
        tvProgress.text = null
        tvBuffering.text = null
        setVideoUrl()
    }

    /**
     * 增加音量
     */
    private fun volumeUp() {
        audioManager.adjustStreamVolume(
            AudioManager.STREAM_MUSIC,
            AudioManager.ADJUST_RAISE,
            AudioManager.FLAG_SHOW_UI
        )
    }

    /**
     * 减少音量
     */
    private fun volumeDown() {
        audioManager.adjustStreamVolume(
            AudioManager.STREAM_MUSIC,
            AudioManager.ADJUST_LOWER,
            AudioManager.FLAG_SHOW_UI
        )
    }

    /**
     * 最大音量
     */
    private fun volumeMax() {
        val maxVol = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC)
        audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, maxVol, AudioManager.FLAG_SHOW_UI)
    }

    /**
     * 静音
     */
    private fun volumeMute() {
        audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, 0, AudioManager.FLAG_SHOW_UI)
    }

    private fun showLoading() {
        loadingView.visibility = View.VISIBLE
    }

    private fun hideLoading() {
        loadingView.visibility = View.GONE
    }

    private fun initVideoView() {
        videoView.setOnInfoListener { _, what, _ ->
            when (what) {
                MediaPlayer.MEDIA_INFO_BUFFERING_START -> {
                    // 播放中缓冲不足（重新缓冲）
                    tvBuffering.text = "缓冲中"
                    showLoading()
                }

                MediaPlayer.MEDIA_INFO_BUFFERING_END -> {
                    tvBuffering.text = "缓冲完成"
                    hideLoading()
                }
            }
            true
        }

        // 首次加载（prepare 阶段）遮罩默认可见，黑屏期间显示 loading
        videoView.setOnPreparedListener { mp ->
            // 保持屏幕常量
            window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)

            // 设置视频画面在渲染区域里的缩放方式
            mp.setVideoScalingMode(MediaPlayer.VIDEO_SCALING_MODE_SCALE_TO_FIT_WITH_CROPPING)

            hideLoading()

            btnStartPause.text = "暂停"
        }

        videoView.setOnErrorListener { _, what, extra ->
            hideLoading()
            tvBuffering.text = "播放出错（what=$what, extra=$extra）"
            true
        }

        // 循环播放
        videoView.setOnCompletionListener {
            Log.e("TAG", "播放完成")
        }

        setVideoUrl()
        playVideo()
    }

    private fun initProgressListener() {
        progressRunnable = Runnable {
            if (videoView.isPlaying) {
                val current = videoView.currentPosition
                val total = videoView.duration
                if (total > 0) {
                    val progress = (current.toFloat() / total * 100).toInt()
                    tvProgress.text = "进度：${progress}"
                    if (progress >= 100) {
                        handler.removeCallbacksAndMessages(null)
                    }
                }
            }
            handler.postDelayed(progressRunnable, 1000L)
        }
        handler.post(progressRunnable)
    }

    override fun onResume() {
        super.onResume()
        videoView.resume()
    }

    override fun onPause() {
        super.onPause()
        videoView.pause()
    }

    override fun onDestroy() {
        super.onDestroy()
        videoView.stopPlayback()
        window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
    }
}