使用Ext的Grid,Form,Dialog来实现分页列表,创建,修改,删除功能

在WEB 应用中,大部分的页面都可以被分为:列表,创建,读取,更新,删除.在Ext的文档中心提供了一个非常好的例子,一个行内编辑的表格.然而,在现实中,行 内编辑的表格是远远不够的,还需要用不同的方式来展示表单.下面的例子中向你展示如何在表格中创建/更新一个对话框表单.

列表功能

首先是是一个权限列表页,它包含分页,查询/过滤功能,创建和删除功能.

先定义数据源:

this.ds = new Ext.data.Store({
                    proxy : new Ext.data.HttpProxy({ url : '/wit/data.shtml' }), //'/wit/data.shtml' 一个读取数据列表的Action
                    reader : new Ext.data.JsonReader({ //使用JSON传输入数据
                        root : 'roleList',
                        totalProperty : 'totalCount',
                        id : 'id'
                    },
                    // 定义字段映射
                    [
                        {
                            name : 'id',
                            mapping : 'id',
                            type : 'string'
                        },
                        {
                            name : 'name',
                            mapping : 'name',
                            type : 'string'
                        },
                        {
                            name : 'description',
                            mapping : 'description',
                            type : 'string'
                        },
                        {
                            name : 'createDate',
                            mapping : 'createDate',
                            type : 'string'
                        },
                        {
                            name : 'updateDate',
                            mapping : 'updateDate',
                            type : 'string'
                        }
                    ]),
                    remoteSort : true
                });
                this.ds.load({ params:{ start : 0, limit : 20 } });

指定数据的来源位置,解析的方式,以及字段的映射.

接下来是表格中表头的定义,匹配上面的字段:

this.cm = new Ext.grid.ColumnModel([
                    {
                        header : '#',
                        dataIndex : 'id',
                        width : 30,
                        sortable : 1
                    },
                    {
                        header : '名称',
                        dataIndex : 'name',
                        width : 140,
                        sortable : 1
                    },
                    {
                        header : '描述',
                        dataIndex : 'description',
                        width : 140,
                        sortable : 1
                    },
                    {
                        header : '创建日期',
                        dataIndex : 'createDate',
                        width : 150,
                        sortable : 1
                    },
                    {
                        header : '修改日期',
                        dataIndex : 'updateDate',
                        width : 150,
                        sortable : 1
                    }
                ]);

再定义一下Grid:

this.grid = new Ext.grid.Grid('htmlGridPanel', {
                    ds : Grid.ds,
                    cm : Grid.cm,
                    enableColLock : false,
                    autoSizeColumns : true,
                    loadMask : true
                });
                this.grid.render();

现在,就可以看到简单的表格了.功能还有待完善.

接下来,在表格的头部面板处,添加过滤/查询的下拉菜单:

this.gridHead = this.grid.getView().getHeaderPanel(true);
                this.toolbar = new Ext.Toolbar(this.gridHead);
                this.filterBtn = new Ext.Toolbar.MenuButton({
                    icon : '../images/class.gif',
                    cls : 'x-btn-text-icon',
                    text : '选择过滤器',
                    tooltip : '选择一个过滤器',
                    menu : { items : [
                        new Ext.menu.CheckItem({ text : '编号', value : 'id', checked : true, group : 'filter', checkHandler : this.onItemCheck}),
                        new Ext.menu.CheckItem({ text : '名称', value : 'name', checked : false, group : 'filter', checkHandler : this.onItemCheck}),
                        new Ext.menu.CheckItem({ text : '描述', value : 'description', checked : false, group : 'filter', checkHandler : this.onItemCheck})
                    ]},
                    minWidth : 105
                });               
                this.toolbar.add(this.filterBtn);       
                this.filter = Ext.get(this.toolbar.addDom({
                    tag : 'input',
                    type : 'text',
                    size : '30',
                    value : '',
                    style : 'background : #F0F0F9;'
                }).el);
                this.filter.on('keypress', function(e) {
                    if (e.getKey() == e.ENTER && this.getValue().length > 0) {
                        Grid.ds.load({ params : { start : 0, limit : 20 }});
                    }
                });   

在表格的底部面板添加分页,添加,删除按钮:

this.gridFoot = this.grid.getView().getFooterPanel(true);               
                this.paging = new Ext.PagingToolbar(this.gridFoot, this.ds, {
                    pageSize : 20,
                    displayInfo : true,
                    displayMsg : '共有 {2} 条记录.当前显示 {0} - {1}条记录.',
                    emptyMsg : '没有记录!'
                });
                this.paging.add('-', {
                    pressed : true,
                    enableToggle : true,
                    text : '添加',
                    cls : '',
                    toggleHandler : this.doAdd
                });
                this.paging.add('-', {
                    pressed : true,
                    enableToggle : true,
                    text : '删除',
                    cls : '',
                    toggleHandler : this.doDel
                });

在分页中,你需要在从服务器端加载数据之前发送过滤的字段和值:

this.ds.on('beforeload', function() {
                    Grid.ds.baseParams = {
                        filterValue : Grid.filter.getValue(),
                        filterTxt : Grid.filterBtn.getText()
                    };
                });
从服务器端返回的列表的JSON结果如下:

{"roleList":[{"id":21,"description":"description21","name":"puras21","createDate":"Fri Sep 07 15:54:44 CST 2007","updateDate":"Fri Sep 07 15:54:44 CST 2007"},{"id":40,"description":"description40","name":"puras40","createDate":"Fri Sep 07 15:54:44 CST 2007","updateDate":"Fri Sep 07 15:54:44 CST 2007"}],"totalCount":2}

删除

删除方法如下:

doDel : function() {
                var c = Grid.grid.getSelections();
                if (c.length > 0)
                    Ext.MessageBox.confirm('消息', '确认要删除所选记录?', Grid.doDelProc);
                else
                    Ext.MessageBox.alert('警告', '最少需要选择一条记录!');   
            },
            doDelProc : function(btn) {
                if (btn == 'yes') {
                    if (Grid.grid.getSelectionModel().hasSelection()) {
                        var ids = new Array();
                        var records = Grid.grid.getSelectionModel().getSelections();
                        for (var i = 0, len = records.length; i < len; i++) {
                            ids[ids.length] = records[i].id;
                        }
                        Ext.lib.Ajax.request(
                            'GET',
                            '/wit/delete.shtml?ids=' + ids,
                            {
                                success : Grid.onSuccess,
                                failure : function(form, action) { Ext.MessageBox.alert('消息', '删除失败!');}
                            },
                            null
                        );
                    }
                }
            },
            onSuccess : function(o) {
                var response = function(json) {
                    try {
                        return eval('(' + json + ')');
                    } catch(e) {}
                    return null;
                }(o.responseText);
                if (response.failure && response.failure == true) {
                    Ext.MessageBox.alert('消息', response.info);
                }
                Grid.ds.reload();
            }

通过Ajax的形式提交到服务器端.如果删除失败,则将失败信息显示给用户.onSuccess可以用于添,删,改三个功能的处理.返回的JSON数据结构如下:

"{success : true, info : '删除成功!'}"

前面已经把列表,分页,删除等部分说完了,这里再把创建和修改说说,基本的功能就差不多了.

创建

在这里,创建和修改者是用Dialog的形式来做的,首先则需要创建相应的DIV:

<!-- add div -->
    <div id="a-addInstance-dlg" style="visibility:hidden;">
        <div class="x-dlg-hd">添加权限</div>
        <div class="x-dlg-bd">
            <div id="a-addInstance-inner" class="x-layout-inactive-content">
                <div id="a-addInstance-form"></div>
            </div>
        </div>       
    </div>

之后就是在这个DIV里创建Form了,直接用Ext的Form组件:

createNewForm : function() {       
                this.name_tf = new Ext.form.TextField({
                    fieldLabel : '名称',
                    name : 'name',
                    allowBlank : false
                });
                this.description_tf = new Ext.form.TextField({
                    fieldLabel : '描述',
                    name : 'description'
                });
                this.addForm = new Ext.form.Form({
                    labelAlign : 'right',
                    url : '/wit/add.shtml'
                });
                this.addForm.column({
                    width : 430,
                    labelWidth : 120,
                    style : 'margin-left : 8px; margin-top : 8px;'
                });
                this.addForm.fieldset(
                    {id : 'desc', legend : '请填写字段值'},
                    Grid.name_tf,
                    Grid.description_tf
                );
                this.addForm.applyIfToFields({ width : 255 });
                this.addForm.render('a-addInstance-form');
                this.addForm.end();
            }

之后别忘了在加载的时候调用这个方法:

this.createNewForm();

Form窗体定义完,现在可以处理前面说的过那个创建按钮的事件了,在这里事件处理的方法名为doAdd:

doAdd : function() {
                if (!Grid.addInstanceDlg) {
                    Grid.addInstanceDlg = Grid.createNewDialog('a-addInstance-dlg');
                    Grid.addInstanceDlg.addButton('重置', Grid.resetForm, Grid.addInstanceDlg);
                    Grid.addInstanceDlg.addButton('保存', Grid.saveNewForm, Grid.addInstanceDlg);
                    var layout = Grid.addInstanceDlg.getLayout();
                    layout.beginUpdate();
                    var t = new Ext.ContentPanel('a-addInstance-inner', {title : 'create account'});
                    layout.add('center', new Ext.ContentPanel('a-addInstance-inner', {title : '添加权限'}));
                    layout.endUpdate();           
                }                   
                Grid.addInstanceDlg.show();           
            }

首先用Grid.createNewDialog创建一个LayoutDialog,之后再把添加里的特有的按钮加上去,然后更新一下Dialog的布局,把它显示出来,这时就可以看到添加的窗体了:

Grid.createNewDialog用于创建和修改时创建对话框,代码如下:

createNewDialog : function(title) {
                var newDialog = new Ext.LayoutDialog(title, {
                    modal : true,
                    autoTabs : true,
                    proxyDrag : true,
                    resizable : false,
                    width : 480,
                    height : 302,
                    shadow : true,
                    center : {
                        autoScroll : true,
                        tabPosition : 'top',
                        closeOnTab : true,
                        closeOnTab : true,
                        alwaysShowTabs : false
                    }
                });
                newDialog.addKeyListener(27, newDialog.hide, newDialog);
                newDialog.addButton('取消', function() { newDialog.hide(); } );
                return newDialog;           
            }

如 果添加成功,则自动关闭这个Dialog,并重新加载列表,如果添加失败,只是简单的弹出一个对话框,提示失败,其实这里可以做的更人性化一些,可以在服 务器端传回错误的原因,比如某字段有问题,可以红色显示出其输入框等等.这里服务端返回的JSON数据与删除返回的一样.

处理代码如下:

saveNewForm : function() {
                if (Grid.addForm.isValid()) {
                    Grid.addForm.submit({
                        waitMsg : '正在保存数据...',
                        reset : true,
                        failure : function(form, action) {
                            Ext.MessageBox.alert('友情提示', action.result.info);
                        },
                        success : function(form, action) {
                            Grid.addInstanceDlg.hide();
                            Grid.ds.reload();
                        }
                    });
                } else {
                    Ext.MessageBox.alert('错误', '字段填写不正确!');
                    Grid.name_tf.focus();
                }
            }

修改

修改则和创建差不多了,不同的有两点,一是事件是在列表的行上双击,来触发事件,弹出修改对话框,另一个则是需要在显示对话框的同时,把所要修改的记录的数据加载进来.

首先在列表加上事件捕捉:

this.grid.on('rowdblclick', this.onRowDbClick, this);   

下面则是处理这个事件的代码:

onRowDbClick : function(grid, rowIndex, e) {
                var selectId = this.ds.data.items[rowIndex].id;
                var roleData = new Ext.data.Store({
                    proxy : new Ext.data.HttpProxy({url : '/wit/edit.shtml?id=' + selectId}),
                    reader : new Ext.data.JsonReader({}, ['id', 'name', 'description']),
                    remoteSort : false
                });
                roleData.on('load', function() {
                    Grid.updateId = roleData.getAt(0).data['id'];
                    Grid.name_show.setValue(roleData.getAt(0).data['name']);
                    Grid.description_show.setValue(roleData.getAt(0).data['description']);
                    if (!Grid.updateInstanceDlg) {
                        Grid.updateInstanceDlg = Grid.createNewDialog('a-updateInstance-dlg');
                        Grid.updateInstanceDlg.addButton('保存', Grid.saveUpdateForm, Grid.updateInstanceDlg);
                        var layout = Grid.updateInstanceDlg.getLayout();
                        layout.beginUpdate();
                        layout.add('center', new Ext.ContentPanel('a-updateInstance-inner', {title : '修改权限'}));
                        layout.endUpdate();
                    }
                    Grid.updateInstanceDlg.show();
                });
                roleData.load();
            }

这里做了两件事,一个是把欲修改的数据加载到本地, 服务端返回的数据结构为:

([{"id":"12","description":"test role 12","name":"puras 12"}])

一个是将数据置入Form窗体的字段中,并将Dialog显示出来.修改的Form与创建的相似:

createEditForm : function() {
                this.name_show = new Ext.form.TextField({
                    fieldLabel : '名称',
                    name : 'name',
                    allowBlank : false
                });
                this.description_show = new Ext.form.TextField({
                    fieldLabel : '名称',
                    name : 'description'
                });
                this.editForm = new Ext.form.Form({
                    labelAlign : 'right',
                    url : '/wit/edit_ok.shtml'
                });
                this.editForm.column({width : 430, labelWidth : 120, style : 'margin-left : 8px; margin-top : 8px;'});
                this.editForm.fieldset(
                    {legend : '请更新字段值'},
                    Grid.name_show,
                    Grid.description_show
                );
                this.editForm.applyIfToFields({width : 255});
                this.editForm.render('a-updateInstance-form');
                this.editForm.end();
            }

这个Form对应的Div为:

<!-- update div -->
    <div id="a-updateInstance-dlg" style="visibility:hidden;">
        <div class="x-dlg-hd">修改权限</div>
        <div class="x-dlg-bd">
            <div id="a-updateInstance-inner" class="x-layout-inactive-content">
                <div id="a-updateInstance-form"></div>
            </div>
        </div>
    </div>

双击某条记录,则会弹出修改Dialog了,大概的样子如下:

修改的处理事件与添加类似,需要注意的地方就是ID是怎么传过去的:

saveUpdateForm : function() {
                if (Grid.editForm.isValid()) {
                    Grid.editForm.submit({
                        params : { id : Grid.updateId},
                        waitMsg : '正在更新数据...',
                        reset : false,
                        failure : function(form, action) {
                                Ext.MessageBox.alert('友情提示', action.result.info);
                            },
                        success : function(form, action) {
                            Grid.updateInstanceDlg.hide();
                            Grid.ds.reload();
                        }
                    });                   
                } else {
                    Ext.MessageBox.alert('错误', '字段填写不正确!');
                }
            }

到此就Over啦,列表,添,删,改都OK了.在没有做的时候,总是感觉找不到入口点,做完之后才发现,原来自己担心的问题,都不是问题,哈,想想,还是挺简单的.