cellselection.js

javascript 很酷的类库

/*
 * Isomorphic SmartClient
 * Version 6.5 (2008-04-30)
 * Copyright(c) 1998-2007 Isomorphic Software, Inc. All rights reserved.
 * "SmartClient" is a trademark of Isomorphic Software, Inc.
 *
 * [e-mail]
 *
 * http://smartclient.com/license
 */

 





//>	@class	CellSelection
//
//	Maintains a representation of selection over a 2-dimensional grid of objects.<br>
//  Automtatically created to manage cell-selection on +link{class:CubeGrid} widgets.
//
// @visibility Analytics
// @treeLocation Client Reference/System/Selection
//<
//	When you create a CellSelection object, set:
// <ul>
//		<li>cellSelection.data - to an array of records referenced by this selection
//		<li>cellSelection.numCols - to the number of columns/fields covered by this selection
//		<li>cellSelection.selectionProperty - to an alternative name for the selection property,
//			if you need to access this property manually
// </ul>

//	Implementation:
//		A uniquely-named selection property is added to each row/record of the data.
//		This property holds an array of numbers, one for each "chunk" of 32 columns,
//		whose bits (0-31) represent the selection state of the cell in the corresponding
//		column/field.

//	TODO:
//		* special case selectSingleCell/deselectSingleCell when we know only one cell can be selected
//		* convert 'select all' to not actually select all, but rather to set a bit?
//		* maybe also special case row/col selection for performance?
//		* hardcode COL_SELECTION_FLAGS table

//
//	create the CellSelection class
//
isc.ClassFactory.defineClass("CellSelection");



isc.CellSelection.addClassProperties({
	_selectionID : 0,			//>	@classAttr	isc.CellSelection._selectionID		(number : 0 : IRWA)
								//			number to generate a unique ID and selectionProperty for each selection
								//		@group	selection
                                //      @visibility internal
								//<
								
	COL_SELECTION_FLAGS : null	// generate when the first cellSelection is instantiated
});



isc.CellSelection.addClassMethods({

generateFlagTable : function () {
	isc.CellSelection.COL_SELECTION_FLAGS = [];
	for (var i = 0; i < 32; i++)
		isc.CellSelection.COL_SELECTION_FLAGS[i] = Math.pow(2,i);
}

});



isc.CellSelection.addProperties( {
	data:null,
	numCols:0,
	selectionProperty:null,
	_dirty:true,
	_selectedCells:[],
	lastSelectedCell:[],
	changedCells:[]	
});



isc.CellSelection.addMethods({



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~ Setup ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

//>	@attr	cellSelection.data  (Array | List: null : IRW)
//    Array (or +link{class:List}) of records to be referenced by this cell selection
//  @visibility serverSelection
//  @group selection
//<

//>	@attr	cellSelection.numCols (number : null : IRW)
//      the number of columns/fields covered by this selection
//  @visibility internal
//  @group selection
//<

//>	@attr	cellSelection.selectionProperty (string : null : IRWA)
//      A name for the selection property.  This property will be set on the records in this
//      selection's data, and used to determine whether records are selected or not.
//      Automatically generated if not specified.
//  @visibility serverSelection
//  @group selection
//<

//>	@method	cellSelection.init()    (A)
//  Initialize this selection instance.<br>
//  Note: if the <code>data</code> property is not set at init time, it should be passed to
//  the selection using the <code>selection.setData</code> method
//
//		@group	selection
//
//		@param	[all arguments]	(object)	objects with properties to override from default
// @visibility serverSelection
//<
init : function () {
	if (!isc.CellSelection.COL_SELECTION_FLAGS) isc.CellSelection.generateFlagTable();
	
	// get unique ID and selection properties
	if (!this.selectionProperty) this.selectionProperty = "_cellSelection_"+isc.CellSelection._selectionID++;

	// set the data object so we get notification for add and delete, etc.
	//	NOTE: if the data object wasn't set, use a new arrays
	this.setData((this.data ? this.data : []));
},



//>	@method	cellSelection.setData()     (A)
//			Initialize selection data.<br><br>
//			Call this method to associate the selection with a different data object.<br>
//          <i>Note: No need to call this if the contents of the selection's data is modified</i>
//		@group	selection
//		@param		newData	(array)		new data to maintain selection in
// @visibility serverSelection
//<
setData : function (newData) {		

	// if we are currently pointing to data, stop observing it
	if (this.data != null) this.ignoreData(this.data);	

	// remember the new data
	this.data = newData;

	// observe the new data so we will update automatically when it changes
	if (this.data != null) this.observeData(this.data);
},


	
//>	@method	cellSelection.observeData()	(A)
//			Observe methods on the data so we change our state.
//			Called automatically by cellSelection.setData().
//		@group	selection
//
//	@param	data	(array)		new data to be observed
// @visibility internal
//<
observeData : function (data) {
	this.observe(data, "dataChanged", "observer._dirty = true");
},



//>	@method	cellSelection.ignoreData()	(A)
//			Stop observing methods on data when it goes out of scope.
//			Called automatically by setData
//		@group	selection
//
//		@param	data	(array)		old data to be ignored
// @visibility internal
//<
ignoreData : function (data) {
	this.ignore(data, "dataChanged");
},



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~ Selection Tests ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



//>	@method	cellSelection.cellIsSelected()
//			Return true if a particular item is selected
//		@group	selection
//
//		@param	rowNum	(number)	row index of the cell to check
//      @param  colNum  (number)    column index of the cell to check
//		@return		(boolean)	true == object is selected
//								false == object is not selected
// @group selection
// @visibility Analytics
//<
cellIsSelected : function (rowNum, colNum) {
	var row = this.data[rowNum],
		rowSelection = (row ? row[this.selectionProperty] : null),
		rowChunkSelection = (rowSelection ? rowSelection[Math.floor(colNum/32)] : null),
		colSelectionFlag = isc.CellSelection.COL_SELECTION_FLAGS[colNum%32];
	return (rowChunkSelection != null && ((rowChunkSelection & colSelectionFlag) != 0));
},



rowHasSelection : function (rowNum) {
	var row = this.data[rowNum],
		rowSelection = (row ? row[this.selectionProperty] : null),
		numRowChunks = Math.ceil(this.numCols/32);
		
	// if row doesn't exist or row selection property is null/zero, return false
	if (!row || !row[this.selectionProperty]) return false;
	
	// otherwise check each chunk of the row for a selection (true == nonzero value)
	for (var i = 0; i < numRowChunks; i++) {
		if (rowSelection[i]) return true;
	}
	// made it through all row chunks with no selection, so return false
	return false;
},


colHasSelection : function (colNum) {
	if (colNum > this.numCols - 1) return false;
	
	var colSelectionFlag = isc.CellSelection.COL_SELECTION_FLAGS[colNum%32],
		rowChunkNum = Math.floor(colNum/32);
	
	// iterate through all rows of data	
    var rows = this.data,
        numRows = rows.length;
	for (var i = 0; i < numRows; i++) {
	
		// get selection property for the current row
		var rowSelection = rows[i][this.selectionProperty];
		
		// if selection property exists, selection chunk is nonzero, and the flag for this column is set, return true
		if (rowSelection && rowSelection[rowChunkNum] && ((rowSelection[rowChunkNum] & colSelectionFlag) != 0))
			return true;
	}
	// made it through all rows with no selection, so return false
	return false;
},


//>	@method	cellSelection.anySelected()
//			Is anything in the list selected?
//		@group	selection
//
//		@return		(boolean)	true == at least one item is selected
//								false == nothing at all is selected
// @visibility Analytics
// @group selection
//<
anySelected : function () {
	var	numRowChunks = Math.ceil(this.numCols/32);

	// iterate through all rows of data
    var rows = this.data,
        numRows = rows.length;

	for (var i = 0; i < numRows; i++) {
	
		// get selection property for the current row
		var rowSelection = rows[i][this.selectionProperty];
		if (!rowSelection) continue;
		
		// check each chunk of the row for a selection (true == nonzero value)
		for (var j = 0; j < numRowChunks; j++) {
			if (rowSelection[j]) return true;
		}
	}
	// made it through all rows with no selection, so return false
	return false;
},



//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~ Selection Getters ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

//>	@method	cellSelection.getSelectedCells()
//  Returns an array of the currently selected cells.  Each cell is returned as a 2 element
//  array in the form <code>[rowNum, colNum]</code>.
// @group  selection
// @return (array)  an array of the selected cells, as 2 element arrays 
// @visibility Analytics
// @group selection
//<
getSelectedCells : function () {
	// first see if we already have a clean list of selected cells
	if (!this._dirty) return this._selectedCells;

	var selectedCells = [],
		colSelectionFlags = isc.CellSelection.COL_SELECTION_FLAGS,
		numRowChunks = Math.ceil(this.numCols/32),
        rows = this.data,
        numRows = rows.length,
        rowSelection;

	// iterate through all rows of data
	for (var i = 0; i < numRows; i++) {
	
		// get selection property for the current row
		rowSelection = rows[i][this.selectionProperty];
		if (!rowSelection) continue;
		
		// iterate through all chunks in this row
		for (var j = 0, rowChunkSelection, numColsInChunk; j < numRowChunks; j++) {
			// get selection flags for this chunk
			rowChunkSelection = rowSelection[j];
			if (!rowChunkSelection) continue;
			
			// how many columns in this chunk (32 for all but the last chunk)
			// NOTE: should use this.numCols%32 for non-chunked CellSelection too
			numColsInChunk = (j == numRowChunks - 1 && this.numCols%32 != 0) ? this.numCols%32 : 32;
			
			// iterate through the flags to find the selected cells in this chunk
			for (var k = 0; k < numColsInChunk; k++) {
				if ((rowChunkSelection & colSelectionFlags[k]) != 0) {
					selectedCells[selectedCells.length] = [i,j*32+k];
				}
			}
		}
	}
		
	// cache and return the list of selected cells
	this._selectedCells = selectedCells;
	this._dirty = false;
	return selectedCells;
},


//	returns an array containing the numbers of all rows that have at least one cell selected
getSelectionRowNums : function () {
	var selectionRowNums = [],
		numRowChunks = Math.ceil(this.numCols/32), 
        rows = this.data, 
        numRows = rows.length, 
        rowSelection;

	// iterate through all rows of data
	for (var i = 0; i < numRows; i++) {
	
		// get selection property for the current row
		rowSelection = rows[i][this.selectionProperty];
		if (!rowSelection) continue;
		
		// iterate through chunks in this row
		for (var j = 0, numColsInChunk; j < numRowChunks; j++) {
			// if any selection flags are set, add the current row's number to the list we'll return
			if (rowSelection[j]) {