如何在鼠标单击时设置可拖动事件?

时间:2013-11-06 04:32:45

标签: javascript html5 html5-canvas kineticjs

当我同时点击并拖动鼠标左键和鼠标键时,我可以设置舞台的可拖动事件。

1 个答案:

答案 0 :(得分:2)

如果你想阻止拖动,直到左右两边都有。按下右键,你可以设置一个形状的dragBoundFunc来限制所有拖动,直到你说它可以拖动(当你看到两个按钮都关闭时)

这是关于dragBoundFunc的链接:

http://www.html5canvastutorials.com/kineticjs/html5-canvas-drag-and-drop-shapes-horizontally-or-vertically-tutorial/

以下是一些入门代码:

// add properties to tell whether left/right buttons are currently down

myShape.leftIsDown=false;
myShape.rightIsDown=false;

// add mousedown to set the appropriate button flag to true

myShape.on("mousedown",function(event){
    if(event.button==0){this.leftIsDown=true;}
    if(event.button==2){this.rightIsDown=true;}
});

// add mouseup to set the appropriate button flag to false

myShape.on("mouseup",function(event){
    if(event.button==0){this.leftIsDown=false;}
    if(event.button==2){this.rightIsDown=false;}
});

// add a dragBoundFunc to the shape
// If both buttons are pressed, allow dragging
// If both buttons are not pressed, prevent dragging

dragBoundFunc: function(pos) {
    if(this.leftIsDown && this.rightIsDown){
        // both buttons are down, ok to drag
        return { pos }
    }else{
        // both buttons aren't down, refuse to drag
        return {
          x: this.getAbsolutePosition().x,
          y: this.getAbsolutePosition().y
        }
    }
}