用仿ActionScript的语法来编写html5——第六篇，TextField与输入框
一，对比
1,html5中
首先看看在html5的canvas中的文字显示
var canvas = document.getElementById("myCanvas");
var context = canvas.getContext("2d");
context.font = "40pt Calibri";
context.fillStyle = "#0000ff";
context.fillText("文字测试!", 50, 150);在html中输入框就不用说了，需要用到input标签
<input type="text" id="myTextbox" />
2,在as中
//文字显示 var txt:TextField = new TextField(); txt.text = "文字测试!"; txt.x = 50; txt.y = 50; addChild(txt); //输入框 var txt:TextField = new TextField(); txt.type = TextFieldType.INPUT; txt.x = 50; txt.y = 50; addChild(txt);
二,编写js类库后的代码
//文字显示 var txt = new LTextField(); txt.x = 100; txt.text = "TextField 测试"; addChild(txt); //输入框 var txt1 = new LTextField(); txt1.x = 100; txt1.y = 50; txt1.setType(LTextFieldType.INPUT); addChild(txt1);
三,实现方法
文字显示非常简单，只需要建立一个LTextField类和一个show方法就可以了function LTextField(){
var self = this;
self.objectindex = ++LGlobal.objectIndex;
self.type = "LTextField";
self.texttype = null;
self.x = 0;
self.y = 0;
self.text = "";
self.font = "utf-8";
self.size = "11";
self.color = "#000000";
self.textAlign = "left";
self.textBaseline = "middle";
self.lineWidth = 1;
self.stroke = false;
self.visible=true;
}
LTextField.prototype = {
show:function (cood){
if(cood==null)cood={x:0,y:0};
var self = this;
if(!self.visible)return;
LGlobal.canvas.font = self.size+"pt "+self.font;
LGlobal.canvas.textAlign = self.textAlign;
LGlobal.canvas.textBaseline = self.textBaseline;
LGlobal.canvas.lineWidth = self.lineWidth;
if(self.stroke){
LGlobal.canvas.strokeStyle = self.color;
LGlobal.canvas.strokeText(self.text,parseFloat(cood.x) + parseFloat(self.x),
parseFloat(cood.y) + parseFloat(self.y) + parseFloat(self.size));
}else{
LGlobal.canvas.fillStyle = self.color;
LGlobal.canvas.fillText(self.text,parseFloat(cood.x) + parseFloat(self.x),
parseFloat(cood.y) + parseFloat(self.y) + parseFloat(self.size));
}
}
}代码不难理解，就是调用show方法的时候，把它画在canvas上面而已，
关键是输入框，因为html中，输入框是一个标签，怎么把这个标签画到canvas上？或者说canvas可以直接现实输入框？
这个我不太清楚，如果有高手知道的话，希望能告诉偶一声，
我现在说一说我的做法，我是在textField是input的时候，先画一个矩形方框，然后利用div，把textbox直接显示在相应的位置上
我的html里一开始只有下面代码
<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>仿ActionScript测试-TextField</title> <script type="text/javascript" src="../legend/legend.js"></script> <script type="text/javascript" src="./js/Main.js"></script> </head> <body> <div id="mylegend">页面读取中……</div> </body> </html>
然后，利用javascript写入一个canvas和一个textbox，作为准备工作
LGlobal.object = document.getElementById(id); LGlobal.object.innerHTML='<div id="' + LGlobal.id + '_inittxt" style="position:absolute;margin:0px 0px 0px 0px;width:'+width+'px;height:'+height+'px;">数据读取中……</div>' + '<div style="position:absolute;margin:0px 0px 0px 0px;z-index:0;"> <canvas id="' + LGlobal.id + '_canvas">您的浏览器不支持HTML5</canvas></div>'+ '<div id="' + LGlobal.id + '_InputText" style="position:absolute;margin:0px 0px 0px 0px;z-index:10;display:none;"> <input type="text" id="' + LGlobal.id + '_InputTextBox" /></div>'; LGlobal.canvasObj = document.getElementById(LGlobal.id+"_canvas"); LGlobal.inputBox = document.getElementById(LGlobal.id + '_InputText'); LGlobal.inputTextBox = document.getElementById(LGlobal.id + '_InputTextBox'); LGlobal.inputTextField = null;
一开始将textbox隐藏，然后的做法是，当点击我画的矩形方框的时候，将它显示到矩形方框上面，然后当点击其他地方的时候，把输入的内容赋值给textField后隐藏textbox
具体做法不多说了，下面是完整的LTextField代码，或者你一会儿可以直接鼠标右健看完整代码function LTextField(){
var self = this;
self.objectindex = ++LGlobal.objectIndex;
self.type = "LTextField";
self.texttype = null;
self.x = 0;
self.y = 0;
self.text = "";
self.font = "utf-8";
self.size = "11";
self.color = "#000000";
self.textAlign = "left";
self.textBaseline = "middle";
self.lineWidth = 1;
self.stroke = false;
self.visible=true;
}
LTextField.prototype = {
show:function (cood){
if(cood==null)cood={x:0,y:0};
var self = this;
if(!self.visible)return;
if(self.texttype == LTextFieldType.INPUT){
self.inputBackLayer.show({x:self.x+cood.x,y:self.y+cood.y});
if(LGlobal.inputBox.name == "input"+self.objectindex){
LGlobal.inputBox.style.marginTop = (self.y+cood.y) + "px";
LGlobal.inputBox.style.marginLeft = (self.x+cood.x) + "px";
}
}
LGlobal.canvas.font = self.size+"pt "+self.font;
LGlobal.canvas.textAlign = self.textAlign;
LGlobal.canvas.textBaseline = self.textBaseline;
LGlobal.canvas.lineWidth = self.lineWidth;
if(self.stroke){
LGlobal.canvas.strokeStyle = self.color;
LGlobal.canvas.strokeText(self.text,parseFloat(cood.x) + parseFloat(self.x),
parseFloat(cood.y) + parseFloat(self.y) + parseFloat(self.size));
}else{
LGlobal.canvas.fillStyle = self.color;
LGlobal.canvas.fillText(self.text,parseFloat(cood.x) + parseFloat(self.x),
parseFloat(cood.y) + parseFloat(self.y) + parseFloat(self.size));
}
},
setType:function(type){
var self = this;
if(self.texttype != type && type == LTextFieldType.INPUT){
self.inputBackLayer = new LSprite();
self.inputBackLayer.graphics.drawRect(1,"black",[0, 0, 150, 20],true,"#cccccc");
self.inputBackLayer.addEventListener(LMouseEvent.MOUSE_DOWN, function(){
if(self.texttype != LTextFieldType.INPUT)return;
LGlobal.inputBox.style.display = "";
LGlobal.inputBox.name = "input"+self.objectindex;
LGlobal.inputTextField = self;
LGlobal.inputTextBox.value = self.text;
});
}else{
self.inputBackLayer = null;
}
self.texttype = type;
},
mouseEvent:function (event,type,cood){
if(cood==null)cood={x:0,y:0};
var self = this;
if(self.inputBackLayer == null)return;
self.inputBackLayer.mouseEvent(event,type,{x:self.x+cood.x,y:self.y+cood.y});
}
}以上就是用仿ActionScript的语法来编写html5——第六篇，TextField与输入框的内容，更多相关内容请关注PHP中文网（m.sbmmt.com）！
