textareaitem.js

javascript 很酷的类库

    
                // disable native autoComplete 
                (this._getAutoCompleteSetting() != "native" ? " AUTOCOMPLETE=OFF " : ""),
        
                // enable / disable native spellcheck in Moz
                // Same setting in Safari - see comments in TextItem.js
                ((isc.Browser.isMoz || isc.Browser.isSafari) ? 
                    (this.getBrowserSpellCheck() ? " spellcheck=true" : " spellcheck=false") :
                    null),
        
                " WRAP=", this.wrap,
    
                " TABINDEX=", this._getElementTabIndex(),
                (this.showTitle == false && this.accessKey != null ? 
                    " ACCESSKEY=" + this.accessKey : ""),
                    
                // If this browser supports the "input" event write out a handler for it.
                (this._willHandleInput ? " ONINPUT='" + this.getID() + "._handleInput()'" 
                                       : null),
                                       
                // If the readonly property is set, set it on the handle too
                (this.readOnly ? " READONLY=TRUE" : null),
                                        
                // Ensure we pass events through the ISC event handling system.
                " handleNativeEvents=false></TEXTAREA>"
			);
        }
            
        //this.logWarn("textArea HTML:"+ output);
		return output.release();
	},
    
    // Override _nativeElementBlur to fire 'change' explicitly in response to blur rather than
    // relying on the native 'ONCHANGE' handler method
    // (as with textItem)
    _nativeElementBlur : function (element, itemID) {
        var returnVal = this.Super("_nativeElementBlur", arguments);
        
        if (this.changeOnBlur) this.form.elementChanged(this);
        else {
            var elementValue = this.getElementValue();
            // unmap the value if necessary 
            if (this.mapDisplayToValue) {
                elementValue = this.mapDisplayToValue(elementValue);
            }
            if (this._value != elementValue) this.form.elementChanged(this);
        }
        
        return returnVal;
    },

	//>	@method	textAreaItem.getElementStyleHTML()	(I)
    //      	Get the HTML string used to set the visual characteristics for a textArea item.
    //          This includes the STYLE=... & CLASS=... properties to be written into this
    //          form item's element.
	//			This varies by platform, as we attempt to make Netscape think in pixels rather than 
    //          characters and rows
	//
	//		@group	appearance
	//		@return	(string)    String of HTML containing STYLE=... & CLASS=... properties for 
    //                          this items element.
	//
	//<
	getElementStyleHTML : function () {
        
        var width = this.getTextBoxWidth(),
            height = this.getTextBoxHeight();

        return isc.StringBuffer.concat(
            " CLASS='" + this.getTextBoxStyle(),
            
            (isc.Browser.isMoz && this.wrap.toLowerCase() != "off" ? 
                      "' ROWS=10 COLS=10" : "'"),
            " STYLE='",
            // Ensure there's no margin(helps with sizing and v-alignment with icons)
            
            (isc.Browser.isIE ? "margin-top:-1px;margin-bottom:-1px;margin-left:0px;margin-right:0px;" 
                              : "margin:0px;"),                    
            (isc.isA.Number(width) 	? "WIDTH:" + width + "px;" : ""),
            (isc.isA.Number(height)	? "HEIGHT:" + height + "px;" : ""),
            // text align property, known to be supported in IE6 and Moz/Firefox on
            // Windows, not supported on Safari 1.2
            (this.textAlign ? "text-align:" + this.textAlign + ";" : ""),
             // In Mozilla we must use the 'moz-user-focus' css property to govern
             // whether this element can recieve focus or not.
             (isc.Browser.isMoz ? 
                    "-moz-user-focus:" + (this._getElementTabIndex() > 0 ? "normal;" 
                                                                        : "ignore;") :
                    ""),
            "' ");
    },
	
	//>	@method	textAreaItem.mapValueToDisplay()	(A)
	//	Map from the internal value for this item to the display value.
	//		@group	drawing
	//		@param	internalValue		(string)	Internal value for this item.
	//		@return	(string)	Displayed value corresponding to internal value.
	//<
	mapValueToDisplay : function (internalValue, a,b,c,d) {
        var value = this.invokeSuper(isc.TextAreaItem, "mapValueToDisplay", internalValue, a,b,c,d);
        // always display the empty string for null values, rather than "null" or "undefined"
        if (value == null) value = isc.emptyString;
        return value;
        
	},
	
	//>	@method	textAreaItem.mapDisplayToValue()	(A)
	//	Map from a the display value for this item to the internal value.
	//		@group	drawing
	//
	//		@param	displayValue	(string)	Value displayed to the user.
	//		@return	(string)	Internal value corresponding to that display value.
	//<
	mapDisplayToValue : function (displayValue) {
		var value = this._unmapKey(displayValue);
        // if the value to be saved is an empty string, map it to 'null' if necessary
        if (isc.is.emptyString(value)) value = this._emptyStringValue;
        return value;
        
	},
    
    // override 'setValue' to update the data value to store when the element value is set to 
    // the empty string.
    // See Text item setValue override for full description
    setValue : function (value) {

        
        var undef;
        if (value !== undef && (value == null || isc.is.emptyString(value))) 
            this._emptyStringValue = value;

        // Also clear out the '_hasEditedValue' flag, used to handle line break conversions
        // (See comments by the 'lineBreakValue' property)
        delete this._hasEditedValue;
        return this.Super("setValue", arguments);
            

    },

    // Override 'updateValue()' to set a flag on this item marking it as having been edited.
    // This is used by 'getValue()' to determine whether we should convert line breaks to
    // the lineBreakValue for this item.
    updateValue : function () {
        this._hasEditedValue = true;
        return this.Super("updateValue", arguments);
    },
    
    // Override getValue() to convert any line break characters to this.lineBreakValue.
    // See comments by this.lineBreakValue definition for why we do this.
    getValue : function () {
        var value = this.Super("getValue", arguments);
        if (this._hasEditedValue && isc.isA.String(value)) {
            // replace every line break with our line break char string
            if (!this._lineBreakValueRegex) 
                this._lineBreakValueRegex = new RegExp("(\\r\\n|[\\r\\n])", "g");
            value = "" + value;    
            value = value.replace(this._lineBreakValueRegex, this.lineBreakValue);
        }
        
        return value;
    },
    
    // SCROLLING
    // Add support for programmatic scrolling of TextAreas
    
    
    
    getScrollHeight : function () {
        var element = this._getTextBoxElement();
        if (element == null) return this.getHeight();
        
        return element.scrollHeight;
    },
    
    getScrollWidth : function () {
        var element = this._getTextBoxElement();
        if (element == null) return this.getWidth();
        
        return element.scrollWidth;    
    },
    
    _hscrollOn : function () {
        var element = this._getTextBoxElement();
        return element && element.scrollWidth > element.clientWidth;
    },

    _vscrollOn : function () {
        var element = this._getTextBoxElement();
        return element && element.scrollHeight > element.clientHeight;
    },    
    
    getScrollTop : function () {
        var element = this._getTextBoxElement();
        if (element == null) return 0;
        return element.scrollTop;
    },
    
    getScrollLeft : function () {
        var element = this._getTextBoxElement();
        if (element == null) return 0;
        return element.scrollLeft;
    },
    
    scrollTo : function (left, top) {
        var element = this._getTextBoxElement();
        if (element == null) return;
        if (left != null) element.scrollLeft = left;
        if (top != null) element.scrollTop = top;        
    },
    
    scrollToTop : function () {
        this.scrollTo(null, 0);
    },

    scrollToBottom : function () {
        var maxScroll = this.getScrollHeight() - this.getInnerHeight();
        if (maxScroll >= 0) {
            if (this._hscrollOn()) maxScroll += this.form.getScrollbarSize();
            this.scrollTo(null, maxScroll);
        }
    }

});