内容

• 特性
• 信号
• 方法
• 详细描述

Animation QML Type

所有 QML 动画的基 更多...

import 语句：	import QtQuick 2.7
继承者：	AnchorAnimation , Animator , ParallelAnimation , ParentAnimation , PathAnimation , PauseAnimation , PropertyAction , PropertyAnimation , ScriptAction ，和 SequentialAnimation

• 所有成员列表，包括继承成员

特性

• alwaysRunToEnd : bool
• loops : int
• paused : bool
• running : bool

信号

• started ()
• stopped ()

方法

• complete ()
• pause ()
• restart ()
• resume ()
• start ()
• stop ()

详细描述

The Animation type cannot be used directly in a QML file. It exists to provide a set of common properties and methods, available across all the other animation types that inherit from it. Attempting to use the Animation type directly will result in an error.

特性文档编制

alwaysRunToEnd : bool

This property holds whether the animation should run to completion when it is stopped.

If this true the animation will complete its current iteration when it is stopped - either by setting the running property to false, or by calling the stop() 方法。 complete() method is not effected by this value.

This behavior is most useful when the loops property is set, as the animation will finish playing normally but not restart.

By default, the alwaysRunToEnd property is not set.

注意： alwaysRunToEnd has no effect on animations in a Transition.

loops : int

This property holds the number of times the animation should play.

默认情况下， loops is 1: the animation will play through once and then stop.

If set to Animation.Infinite, the animation will continuously repeat until it is explicitly stopped - either by setting the running property to false, or by calling the stop() 方法。

In the following example, the rectangle will spin indefinitely.

Rectangle {
    width: 100; height: 100; color: "green"
    RotationAnimation on rotation {
        loops: Animation.Infinite
        from: 0
        to: 360
    }
}
							

paused : bool

This property holds whether the animation is currently paused.

The paused property can be set to declaratively control whether or not an animation is paused.

Animations can also be paused and resumed imperatively from JavaScript using the pause() and resume() 方法。

By default, animations are not paused.

running : bool

This property holds whether the animation is currently running.

The running property can be set to declaratively control whether or not an animation is running. The following example will animate a rectangle whenever the MouseArea is pressed.

Rectangle {
    width: 100; height: 100
    NumberAnimation on x {
        running: myMouse.pressed
        from: 0; to: 100
    }
    MouseArea { id: myMouse }
}
									

Likewise, the running property can be read to determine if the animation is running. In the following example the Text item will indicate whether or not the animation is running.

NumberAnimation { id: myAnimation }
Text { text: myAnimation.running ? "Animation is running" : "Animation is not running" }
									

Animations can also be started and stopped imperatively from JavaScript using the start() and stop() 方法。

By default, animations are not running. Though, when the animations are assigned to properties, as property value sources using the on syntax, they are set to running by default.

信号文档编制

started ()

This signal is emitted when the animation begins.

It is only triggered for top-level, standalone animations. It will not be triggered for animations in a Behavior or Transition, or animations that are part of an animation group.

相应处理程序是 onStarted .

stopped ()

This signal is emitted when the animation ends.

The animation may have been stopped manually, or may have run to completion.

It is only triggered for top-level, standalone animations. It will not be triggered for animations in a Behavior or Transition, or animations that are part of an animation group.

若 alwaysRunToEnd is true, this signal will not be emitted until the animation has completed its current iteration.

相应处理程序是 onStopped .

方法文档编制

complete ()

Stops the animation, jumping to the final property values

If the animation is not running, calling this method has no effect. The running property will be false following a call to complete() .

不像 stop() , complete() immediately fast-forwards the animation to its end. In the following example,

Rectangle {
    NumberAnimation on x { from: 0; to: 100; duration: 500 }
}
												

调用 stop() at time 250ms will result in the x property having a value of 50, while calling complete() will set the x property to 100, exactly as though the animation had played the whole way through.

pause ()

Pauses the animation

If the animation is already paused or not running , calling this method has no effect. The paused property will be true following a call to pause() .

restart ()

Restarts the animation

This is a convenience method, and is equivalent to calling stop() and then start() .

resume ()

Resumes a paused animation

If the animation is not paused or not running , calling this method has no effect. The paused property will be false following a call to resume() .

start ()

Starts the animation

If the animation is already running, calling this method has no effect. The running property will be true following a call to start() .

stop ()

Stops the animation

If the animation is not running, calling this method has no effect. Both the running and paused properties will be false following a call to stop() .

Normally stop() stops the animation immediately, and the animation has no further influence on property values. In this example animation

Rectangle {
    NumberAnimation on x { from: 0; to: 100; duration: 500 }
}
																	

was stopped at time 250ms, the x property will have a value of 50.

However, if the alwaysRunToEnd property is set, the animation will continue running until it completes and then stop. The running property will still become false immediately.