AS3 将键盘事件更改为鼠标事件答案

【问题标题】：AS3 changing KeyboardEvents to MouseEventsAS3 将键盘事件更改为鼠标事件
【发布时间】：2015-02-08 14:08:05
【问题描述】：

我正在使用 Adobe Flash CS6 学习 AS3，我正在编写一个使用 KeyboardEvents 创建带有动画的移动对象的教程，它运行良好，但现在我想更改它，以便我可以使用屏幕 (MouseEvents) 来移动角色，但我不知道该怎么做。

var movingRight;
var movingLeft;

function onKeyPress(e:KeyboardEvent):void
{
    if(e.keyCode == Keyboard.RIGHT){
        movingRight=1;
    }
    else if(e.keyCode == Keyboard.LEFT){
        movingLeft=1;
    }
}

【问题讨论】：

标签： actionscript-3 flash

【解决方案1】：

要使用按钮移动character，您必须使用两个MouseEvents：按下按钮时的MouseEvent.MOUSE_DOWN事件和释放按钮时的MouseEvent.MOUSE_UP，所以你可以这样做：

LeftBTN.addEventListener(MouseEvent.MOUSE_DOWN, LeftBTN_onPress);
LeftBTN.addEventListener(MouseEvent.MOUSE_UP, LeftBTN_onRelease);
function LeftBTN_onPress(e:MouseEvent):void
{
    movingLeft = 1;
}
function LeftBTN_onRelease(e:MouseEvent):void
{
    character.gotoAndStop(1);
    movingLeft = 0;
}

RightBTN.addEventListener(MouseEvent.MOUSE_DOWN, RightBTN_onPress);
RightBTN.addEventListener(MouseEvent.MOUSE_UP, RightBTN_onRelease);
function RightBTN_onPress(e:MouseEvent):void
{
    movingRight = 1;
}
function RightBTN_onRelease(e:MouseEvent):void
{
    character.gotoAndStop(4);
    movingRight = 0;
}

您也可以像这样为所有事件侦听器使用一个函数：

stage.addEventListener(KeyboardEvent.KEY_DOWN, move_character);
stage.addEventListener(KeyboardEvent.KEY_UP, move_character);
LeftBTN.addEventListener(MouseEvent.MOUSE_DOWN, move_character);
LeftBTN.addEventListener(MouseEvent.MOUSE_UP, move_character);
RightBTN.addEventListener(MouseEvent.MOUSE_DOWN, move_character);
RightBTN.addEventListener(MouseEvent.MOUSE_UP, move_character);

function move_character(e:*){

    var event_type:String = e.type;                     // get event type : to identify which kind of event is fired
    var current_target:String = e.currentTarget.name;   // get target name : to identify the target of the fired event

    switch (event_type){

        case MouseEvent.MOUSE_DOWN :

            if(current_target == 'LeftBTN') movingLeft = 1;
            else movingRight = 1;

            break;

        case MouseEvent.MOUSE_UP:

            if(current_target == 'LeftBTN'){
                character.gotoAndStop(1);
                movingLeft = 0;
            } else {
                character.gotoAndStop(4);
                movingRight = 0;
            }           
            break;      

        case KeyboardEvent.KEY_DOWN:

            if (e.keyCode == Keyboard.RIGHT){           
                movingRight = 1;            
            } else if (e.keyCode == Keyboard.LEFT) {            
                movingLeft = 1;         
            }           
            break;

        case KeyboardEvent.KEY_UP:

            if (e.keyCode == Keyboard.LEFT) {           
                character.gotoAndStop(1);
                movingLeft = 0;         
            } else if (e.keyCode == Keyboard.RIGHT) {           
                character.gotoAndStop(4);
                movingRight = 0;            
            }
            break;
    }

}

或者，使用e 参数作为Event：

function move_character(e:Event){

    var event_type:String = e.type;                     // get event type : to identify which kind of event is fired
    var current_target:String = e.currentTarget.name;   // get target name : to identify the target of the fired event
    var key_code:Number;

    switch (event_type){

        case MouseEvent.MOUSE_DOWN :

            if(current_target == 'LeftBTN') movingLeft = 1;
            else movingRight = 1;

            break;

        case MouseEvent.MOUSE_UP:

            if(current_target == 'LeftBTN'){
                character.gotoAndStop(1);
                movingLeft = 0;
            } else {
                character.gotoAndStop(4);
                movingRight = 0;
            }           
            break;      

        case KeyboardEvent.KEY_DOWN:

            key_code = KeyboardEvent(e).keyCode;

            if (key_code == Keyboard.RIGHT){     
                movingRight = 1;            
            } else if (key_code == Keyboard.LEFT) {            
                movingLeft = 1;         
            }           
            break;

        case KeyboardEvent.KEY_UP:

            key_code = KeyboardEvent(e).keyCode;

            if (key_code == Keyboard.LEFT) {           
                character.gotoAndStop(1);
                movingLeft = 0;         
            } else if (key_code == Keyboard.RIGHT) {           
                character.gotoAndStop(4);
                movingRight = 0;            
            }
            break;
    }

}

希望能有所帮助。

【讨论】：

投了反对票。该方法作为无类型参数，这是不好的做法。既然所有事件都从 Event 继承，为什么不将参数输入为 Event？
@BotMaster 我同意你的观点，但我尽量做到简单，因为 OP 在 AS3 的世界中是新的。我将编辑我的答案以添加它。

【解决方案2】：

在舞台上放两个按钮，命名为 btnRight 和 btnLeft，然后使用这段代码

btnLeft.addEventListener(MouseEvent.CLICK, onButtonClick, false, 0, true);
btnRight.addEventListener(MouseEvent.CLICK, onButtonClick, false, 0, true);

function onButtonClick(evt:MouseEvent) {
    if (evt.target == btnLeft) movingLeft = 1;
    else movingRight = 1;
}

我还建议只使用一个名为movingDirection 的变量，它可以是1、0 或-1 :)

【讨论】：