删除焦点按钮

Question

我这里有两个按钮，放大和缩小。我遇到的问题是当我点击几次时（+）它会坚持并继续缩放。

以下是HTML的代码：

            <button id="zoom-in" class="btn-zoom-in" type="button" title="zoom in"></button>
            <button id="zoom-out" class="btn-zoom-out" type="button" title="zoom out" onmouseup="this.blur();"></button>
            <button id="zoom-default" class="btn-zoom-default" type="button" title="Default"></button>

放大功能：

    function zoomIn()
    {
        var activeObject = canvas.getActiveObject();
        if(activeObject!=null)
        {
            if(activeObject==textGroup)
            {   

                if(nameTextObject!=null)
                {
                    nameTextObject.setFontSize(parseInt(nameTextObject.fontSize)+1);
                    nameTextObject.setCoords();
                    wrapText(nameTextObject,true);
                }
                if(dedicationTextObject!=null)
                {
                    dedicationTextObject.setFontSize(parseInt(dedicationTextObject.fontSize)+1);
                    dedicationTextObject.setCoords();
                    wrapText(dedicationTextObject,true);
                }
                if(signatureObject!=null)
                {
                    signatureObject.setFontSize(parseInt(signatureObject.fontSize)+1);
                    signatureObject.setCoords();
                }
                setTextGroup();
                textGroup.setCoords();
                canvas.renderAll();
            }
            if(activeObject.type=='image')
            {
                var height = activeObject.getHeight();
                activeObject.scaleToHeight(height+10);
                activeObject.centerV();
                activeObject.centerH();
                //activeObject.setCoords();
                canvas.renderAll();
            }
            if(activeObject.type=='text')
            {


                    if(activeObject!=signatureObject)
                    {
                        activeObject.setFontSize(parseInt(activeObject.fontSize)+1);
                        canvas.renderAll();
                        wrapText(activeObject,true);
                    }

            }
        }
        restrictScaling(false);
        if(productType=='cylindrical')
        {
                getPreview();
        }
    }