ActionScript-求as2.0小球弹跳效果代码

Answer 1

给你做了个demo 看看吧
主场景：800×600
小球：30×30
小球实例命名为ball_mc
在第一帧放以下代码：

var xSpeed:Number = 0;
var ySpeed:Number = 0;
var g:Number = 1;//重力常量
var upSpeed;
var runStatus = -1;// 1为上升过程 -1为下落过程
function runBall() {
ySpeed = 0;
ball_mc.onEnterFrame = function() {

if (runStatus == -1) {
if (ball_mc._y<400) {
ySpeed += g;
ball_mc._y = ball_mc._y+ySpeed;//向下为正方向
} else {
//delete ball_mc.onEnterFrame;
upSpeed = ySpeed;
ySpeed = 0;
runStatus = 1;
}
}
if (runStatus == 1) {
if (upSpeed>0) {
upSpeed -= g;
trace(upSpeed);
ball_mc._y = ball_mc._y-upSpeed;
} else {
runStatus = -1;
}
}
};
}
//-------------------------拖拽小球----------------------------
ball_mc.onPress = function() {
_root.ball_mc.startDrag();
delete ball_mc.onEnterFrame;
};
ball_mc.onRelease = function() {
_root.ball_mc.stopDrag();
runBall();
};
ball_mc.onReleaseOutside = function() {
_root.ball_mc.stopDrag();
runBall();
};

//---------------------------------主程序-------------------------------------------
runBall();