Video QML 类型

用于展示指定视频的方便类型。更多...

import 语句：	import QtMultimedia 5.15
继承：	Item

所有成员列表，包括继承成员

特性

audioRole : enumeration
autoLoad : bool
autoPlay : bool
availability : enumeration
bufferProgress : real
customAudioRole : string
duration : int
error : enumeration
errorString : string
fillMode : enumeration
flushMode : enumeration
hasAudio : bool
hasVideo : bool
loops : int
metaData : object
muted : bool
notifyInterval : int
orientation : int
playbackRate : real
playbackState : enumeration
playlist : Playlist
position : int
seekable : bool
source : url
status : enumeration
volume : real

信号

paused ()
playing ()
stopped ()

方法

pause ()
play ()
seek ( offset )
stop ()
supportedAudioRoles ()

详细描述

视频 is a convenience type combining the functionality of a MediaPlayer 和 VideoOutput into one. It provides simple video playback functionality without having to declare multiple types.

Video {
    id: video
    width : 800
    height : 600
    source: "video.avi"
    MouseArea {
        anchors.fill: parent
        onClicked: {
            video.play()
        }
    }
    focus: true
    Keys.onSpacePressed: video.playbackState == MediaPlayer.PlayingState ? video.pause() : video.play()
    Keys.onLeftPressed: video.seek(video.position - 5000)
    Keys.onRightPressed: video.seek(video.position + 5000)
}

视频 supports untransformed, stretched, and uniformly scaled video presentation. For a description of stretched uniformly scaled presentation, see the fillMode property description.

另请参阅 MediaPlayer and VideoOutput .

特性文档编制

audioRole : enumeration

This property holds the role of the audio stream. It can be set to specify the type of audio being played, allowing the system to make appropriate decisions when it comes to volume, routing or post-processing.

The audio role must be set before setting the source property.

可以检索支持的值，采用 supportedAudioRoles() .

值可以是之一：

MediaPlayer .UnknownRole - the role is unknown or undefined.
MediaPlayer .MusicRole - music.
MediaPlayer .VideoRole - soundtrack from a movie or a video.
MediaPlayer .VoiceCommunicationRole - voice communications, such as telephony.
MediaPlayer .AlarmRole - alarm.
MediaPlayer .NotificationRole - notification, such as an incoming e-mail or a chat request.
MediaPlayer .RingtoneRole - ringtone.
MediaPlayer .AccessibilityRole - for accessibility, such as with a screen reader.
MediaPlayer .SonificationRole - sonification, such as with user interface sounds.
MediaPlayer .GameRole - game audio.
MediaPlayer .CustomRole - The role is specified by customAudioRole .

customAudioRole is cleared when this property is set to anything other than CustomRole.

该特性在 Qt 5.6 引入。

autoLoad : bool

This property indicates if loading of media should begin immediately.

Defaults to true, if false media will not be loaded until playback is started.

autoPlay : bool

This property determines whether the media should begin playback automatically.

Setting to true also sets autoLoad to true 。默认为 false .

availability : enumeration

Returns the availability state of the video instance.

This is one of:

值	描述
MediaPlayer .Available	The video player is available to use.
MediaPlayer .Busy	The video player is usually available, but some other process is utilizing the hardware necessary to play media.
MediaPlayer .Unavailable	There are no supported video playback facilities.
MediaPlayer .ResourceMissing	There is one or more resources missing, so the video player cannot be used. It may be possible to try again at a later time.

bufferProgress : real

This property holds how much of the data buffer is currently filled, from 0.0 (empty) to 1.0 (full).

customAudioRole : string

This property holds the role of the audio stream when the backend supports audio roles unknown to Qt. It can be set to specify the type of audio being played, allowing the system to make appropriate decisions when it comes to volume, routing or post-processing.

The audio role must be set before setting the source property.

audioRole is set to CustomRole when this property is set.

该特性在 Qt 5.11 引入。

duration : int

This property holds the duration of the media in milliseconds.

If the media doesn't have a fixed duration (a live stream for example) this will be 0.

error : enumeration

This property holds the error state of the video. It can be one of:

MediaPlayer . NoError - there is no current error.
MediaPlayer .ResourceError - the video cannot be played due to a problem allocating resources.
MediaPlayer .FormatError - the video format is not supported.
MediaPlayer .NetworkError - the video cannot be played due to network issues.
MediaPlayer .AccessDenied - the video cannot be played due to insufficient permissions.
MediaPlayer .ServiceMissing - the video cannot be played because the media service could not be instantiated.

errorString : string

This property holds a string describing the current error condition in more detail.

fillMode : enumeration

Set this property to define how the video is scaled to fit the target area.

VideoOutput .Stretch - the video is scaled to fit
VideoOutput .PreserveAspectFit - the video is scaled uniformly to fit without cropping
VideoOutput .PreserveAspectCrop - the video is scaled uniformly to fill, cropping if necessary

Because this type is for convenience in QML, it does not support enumerations directly, so enumerations from VideoOutput are used to access the available fill modes.

The default fill mode is preserveAspectFit.

flushMode : enumeration

Set this property to define what 视频 should show when playback is finished or stopped.

VideoOutput .EmptyFrame - clears video output.
VideoOutput .FirstFrame - shows the first valid frame.
VideoOutput .LastFrame - shows the last valid frame.

The default flush mode is EmptyFrame.

该特性在 Qt 5.15 引入。

hasAudio : bool

This property holds whether the current media has audio content.

hasVideo : bool

This property holds whether the current media has video content.

loops : int

This property holds the number of times the media is played. A value of 0 or 1 means the media will be played only once; set to MediaPlayer.Infinite 以启用无限循环。

The value can be changed while the media is playing, in which case it will update the remaining loops to the new value.

默认为 1 .

该特性在 Qt 5.9 引入。

metaData : object

This property holds the meta data for the current media.

见 MediaPlayer.metaData for details about each meta data key.

另请参阅 QMediaMetaData .

muted : bool

此特性保持音频输出是否静音。

notifyInterval : int

The interval at which notifiable properties will update.

须申报特性是 position and bufferProgress .

The interval is expressed in milliseconds, the default value is 1000.

该特性在 Qt 5.9 引入。

orientation : int

The orientation of the 视频 in degrees. Only multiples of 90 degrees is supported, that is 0, 90, 180, 270, 360, etc.

playbackRate : real

This property holds the rate at which video is played at as a multiple of the normal rate.

playbackState : enumeration

This read only property indicates the playback state of the media.

MediaPlayer .PlayingState - the media is playing
MediaPlayer .PausedState - the media is paused
MediaPlayer .StoppedState - the media is stopped

The default state is MediaPlayer .StoppedState.

playlist : Playlist

此特性保持用于媒体播放器的播放列表。

设置播放列表特性重置 source 成空字符串。

该特性在 Qt 5.6 引入。

position : int

此特性保持当前的回放位置 (以毫秒为单位)。

要改变此位置，使用 seek() 方法。

另请参阅 seek() .

seekable : bool

This property holds whether the playback position of the video can be changed.

若 true，调用 seek() method will cause playback to seek to the new position.

source : url

此特性保持媒体的源 URL (统一资源定位符)。

Setting the source property clears the current playlist ，若有的话。

status : enumeration

This property holds the status of media loading. It can be one of:

MediaPlayer .NoMedia - no media has been set.
MediaPlayer .Loading - the media is currently being loaded.
MediaPlayer .Loaded - the media has been loaded.
MediaPlayer .Buffering - the media is buffering data.
MediaPlayer .Stalled - playback has been interrupted while the media is buffering data.
MediaPlayer .Buffered - the media has buffered data.
MediaPlayer .EndOfMedia - the media has played to the end.
MediaPlayer .InvalidMedia - the media cannot be played.
MediaPlayer .UnknownStatus - the status of the media cannot be determined.

volume : real

此特性保持音频音量。

按线性比例缩放的音量是从 0.0 (无声) 到 1.0 (全音量)。将钳制超出此范围的值。

默认音量为 1.0 .

通常，UI 音量控件应按非线性比例缩放。例如，使用对数比例缩放将产生感知响度的线性变化，这通常是用户期望的音量控制。见 QtMultimedia.convertVolume() 了解更多细节。

信号文档编制

paused ()

此信号发射，当暂停回放时。

相应处理程序是 onPaused .

注意： 相应处理程序是 onPaused .

playing ()

This signal is emitted when playback is started or continued.

相应处理程序是 onPlaying .

注意： 相应处理程序是 onPlaying .

stopped ()

此信号发射，当停止回放时。

相应处理程序是 onStopped .

注意： 相应处理程序是 onStopped .

方法文档编制

pause ()

暂停媒体回放。

play ()

开始媒体回放。

seek ( offset )

若 seekable property is true, seeks the current playback position to offset .

Seeking may be asynchronous, so the position property may not be updated immediately.

另请参阅 seekable and position .

stop ()

停止媒体回放。

supportedAudioRoles ()

返回支持的音频角色列表。

若不支持设置的音频角色，返回空列表。

该方法在 Qt 5.6 引入。

另请参阅 audioRole .