1)解决之道:

1.修改tabPanel

var tabs= new Ext.TabPanel({ 
        border: false,
            region:'center',
            id:'center',
            activeTab:0,
            items: [{ 

2.将tabPanel的每个子项设置为border布局,然后每个grid设置region为center

 var tabs= new Ext.TabPanel({ 
        border: false,
            region:'center',
            id:'center',
            activeTab:0,
            items: [{ 
                title: 'First tab', 
                //layout: 'fit', 
                layout:'border',
                items: [grid]
            },{ 
                title: 'Second tab' 
            }] 
        });

2)效果:

ext布局问题之tab panel内的gridpanel内容数据变多,出现滚动条_java

3)代码:

1.js

Ext.require('Ext.tab.*');
var tabs;
var tab1store;
var tab2mainStore;
var tab3mainStore;

Ext.onReady(function () {
    //tabl1
    Ext.tip.QuickTipManager.init();
    Ext.QuickTips.init();
    Ext.define('tab1Model', {
        extend: 'Ext.data.Model',
        fields: [
            //'title', 'forumtitle', 'forumid', 'username',
            //{ name: 'replycount', type: 'int' },
            //{ name: 'lastpost', mapping: 'lastpost', type: 'date', dateFormat: 'timestamp' },
            //'lastposter', 'excerpt', 'threadid'
            'ObjectID', 'Content', 'type', 'creator', 'createtime'
        ],
        idProperty: 'ObjectID'
    });

    // create the Data Store
    tab1store = Ext.create('Ext.data.Store', {
        pageSize: 2,
        model: 'tab1Model',
        remoteSort: true,
        proxy: {
            // load using script tags for cross domain, if the data in on the same domain as
            // this page, an HttpProxy would be better
            type: 'ajax',
            extraParams: { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val(), State: "Tempsave" },
            //type: 'json',
            url: '../../Ashx/GetCachetApplyWorkHighSpeed.ashx',
            reader: {
                //type: 'json' //返回数据类型为json格式
                root: 'data',
                totalProperty: 'totalCount'
            },
            // sends single sort as multi parameter
            simpleSortMode: true
        }
        //,
        //sorters: [{
        //    property: 'lastpost',
        //    direction: 'DESC'
        //}]
    });

    var pluginExpanded = true;
    var grid = Ext.create('Ext.grid.Panel', {
        //width: "100%",
        //height: 470,
        //autoHeight: false,
        region: 'center',
        title: 'tab1',
        header: false,
        store: tab1store,
        disableSelection: true,
        loadMask: true,
        viewConfig: {
            id: 'gv',
            trackOver: false,
            stripeRows: false,
            plugins: [{
                ptype: 'preview',
                bodyField: 'excerpt',
                expanded: true,
                pluginId: 'preview'
            }]
        },
        // grid columns
        columns: [{
            id: 'ObjectID',
            text: "用章事由",
            dataIndex: 'Content',
            flex: 1,
            renderer: function (value, metaData, record, rowIndex, colIndex, store) {
                return '<a href="cachetapply.html?CachetApplyID=' + record.data.ObjectID + '">' + value + '</a>';
            },
            sortable: false
        }, {
            text: "类型",
            dataIndex: 'type',
            width: 100,
            hidden: true,
            sortable: true
        }, {
            text: "时间",
            dataIndex: 'createtime',
            width: 250,
            align: 'right',
            sortable: true
        }, {
            text: "删除",
            xtype: 'actioncolumn',
            width: 100,
            sortable: false,
            menuDisabled: true,
            items: [{
                icon: '../../App_Themes/Glass/Images/Icon/delete.GIF',
                tooltip: '删除',
                scope: this,
                handler: function (grid, rowIndex) {
                    var objectid = tab1store.getAt(rowIndex).data.ObjectID;
                    Ext.MessageBox.confirm('提示', '确定删除吗?', function (btn) {
                        if (btn == "yes") {
                            Ext.Ajax.request({
                                method: 'get',
                                url: '../../Ashx/DeleteCachetApplyByObjeID.ashx',
                                params: { ObjectID: objectid },//jsonData: Ext.encode(list),
                                success: function (response) {
                                    Ext.Msg.alert("提示", "删除成功!");
                                    tab1store.reload();
                                
                                },
                                failure: function () {
                                    Ext.Msg.alert("错误", "与后台联系的时候出了问题。");
                                }
                            })
                        }
                    });
                    //insideGridStore.removeAt(rowIndex);
                }
            }]
        }],
        // paging bar on the bottom
        bbar: Ext.create('Ext.PagingToolbar', {
            store: tab1store,
            displayInfo: true,
            displayMsg: 'Displaying data {0} - {1} of {2}',
            emptyMsg: "No data to display"
        })
    });

    // trigger the data store load
    tab1store.loadPage(1);

    //tab1结束

    //tab2开始

    Ext.define('tab2Model', {
        extend: 'Ext.data.Model',
        fields: [
                { name: 'ObjectID' },
                { name: 'Content' },
                { name: 'type' },
                { name: 'creator' },
                { name: 'createdate' },
                { name: 'CategoryID' },
                { name: 'actor' },
                { name: 'url' },
                { name: 'dispatchid' }

        ]
    });

    tab2mainStore = Ext.create('Ext.data.ArrayStore', {
        model: 'tab2Model',
        autoLoad: true,
        proxy: {
            // load using script tags for cross domain, if the data in on the same domain as
            // this page, an HttpProxy would be better
            type: 'ajax',
            extraParams: { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val(), State: "Running" },
            //type: 'json',
            url: '../../Ashx/GetCachetApplyWorkHighSpeed.ashx',
            reader: {
                //type: 'json' //返回数据类型为json格式
                root: 'data',
                totalProperty: 'totalCount'
            },
            // sends single sort as multi parameter
            simpleSortMode: true
        }
    });

    function displayInnerGrid(renderId) {
        Ext.define('TestModel', {
            extend: 'Ext.data.Model',
            fields: [
                { name: 'OpinionID' },
                { name: 'objectid' },
                { name: 'ApproveUserID' },
                { name: 'ApproveUserName' },
                { name: 'ApproveTime' },
                { name: 'Content' },
                { name: 'ConfirmType' }
            ]
        });
        var insideGridStore = Ext.create('Ext.data.ArrayStore', {
            model: 'TestModel',
            //data: dummyDataForInsideGrid,
            autoLoad: true,
            proxy: {
                type: 'ajax',
                //filterParam: 'sysid',
                //simpleSortMode: true,
                //// The PHP script just use query=<whatever>
                //encodeFilters: function(renderId) {
                //    return renderId;
                //},
                //autoSync:true,
                extraParams: {
                    PrimaryId: renderId
                },
                writer: { type: "json" },
                // url: ApiUrl + "ZbbInfo/GetZbbInfoList?sysid=" + renderId,
                url: "../../Ashx/GetOpinionHistoryByPrimaryId.ashx",
                reader: {
                    type: 'json'
                }
            }
        });

        innerGrid = Ext.create('Ext.grid.Panel', {
            store: insideGridStore,
            selModel: {
                selType: 'cellmodel'
            },

            title: '假期值班人员',
            header: false,
            columns: [
                {
                    text: "审批人", dataIndex: 'ApproveUserName', flex: 1, width: 250
                },
                {
                    text: "意见", dataIndex: 'Content', width: 250
                },
                {
                    text: "审批时间", dataIndex: 'ApproveTime', width: 250
                },
                {
                    text: "流程角色", dataIndex: 'ConfirmType', width: 250
                }
            ],
            columnLines: true,
            //autoWidth: true,
            //autoHeight: true,
            autoHeight: true,
            width: "99%",
            //height: 500,
            frame: false,
            iconCls: 'icon-grid',
            renderTo: renderId
        });
        innerGrid.getEl().swallowEvent([
                    'mousedown', 'mouseup', 'click',
                    'contextmenu', 'mouseover', 'mouseout',
                    'dblclick', 'mousemove'
        ]);
    }


    function destroyInnerGrid(record) {

        var parent = document.getElementById(record.get('ObjectID'));
        var child = parent.firstChild;

        while (child) {
            child.parentNode.removeChild(child);
            child = child.nextSibling;
        }

    }


    Ext.define('MainGrid', {
        extend: 'Ext.grid.Panel',
        alias: 'widget.MainGrid',
        region: 'center',
        store: tab2mainStore,
        autoScroll: true,
        viewConfig: {
            style: { overflow: 'auto', overflowX: 'hidden' }
        },
        columns: [
                {
                    id: 'ObjectID',
                    text: "用章事由",
                    dataIndex: 'Content',
                    flex: 1,
                    width: 100,
                    renderer: function (value, metaData, record, rowIndex, colIndex, store) {

                        //(string.IsNullOrEmpty(Eval("DispatchId").ToString()) && string.IsNullOrEmpty(Eval("url").ToString())) ?

                        //(Eval("CategoryID").ToString() == "2" ? "CachetApplyInfo.aspx?CachetApplyID=" + Eval("ObjectID").ToString() : "../ReviceDoc/RevDocShow.aspx?RevDocID=" + Eval("ObjectID").ToString() + "&type=6") : Request.ApplicationPath + "/" + Eval("url").ToString() + "?DispatchID=" + Eval("DispatchID").ToString() + "&mode=Edit"


                        //(string.IsNullOrEmpty(Eval("DispatchId").ToString()) && string.IsNullOrEmpty(Eval("url").ToString())) ?

                        // CachetApplyInfo.aspx?CachetApplyID=" + Eval("ObjectID").ToString() 
                        //Request.ApplicationPath + "/" + Eval("url").ToString() + "?DispatchID=" + Eval("DispatchID").ToString() + "&mode=Edit"
                        if (record.data.url || record.data.dispatchid) {
                            //Request.ApplicationPath + "/" + Eval("url").ToString() + "?DispatchID=" + Eval("DispatchID").ToString() + "&mode=Edit"
                            return '<a href="../../' + record.data.url + '?DispatchId=' + record.data.dispatchid + '&mode=Edit">' + value + '</a>';
                        } else {
                            //CachetApplyInfo.aspx?CachetApplyID=" + Eval("ObjectID").ToString() 
                            return '<a href="../../Cachet/CachetApplyInfo.aspx?CachetApplyID=' + record.data.ObjectID + '">' + value + '</a>';
                        }
                        
                    },
                    sortable: false
                }, {
                    text: "类型",
                    dataIndex: 'type',
                    width: 100,
                    //hidden: true,
                    sortable: true
                }, {
                    text: "时间",
                    dataIndex: 'createdate',
                    width: 250,
                    align: 'right',
                    sortable: true
                }, {
                    text: "当前审批人",
                    dataIndex: 'actor',
                    width: 250,
                    align: 'right',
                    sortable: true
                }
        ],
        selModel: {
            selType: 'cellmodel'
        },
        plugins: [{
            ptype: 'rowexpander',
            rowBodyTpl: [
                    '<div id="{ObjectID}">',
                    '</div>'
            ]
        }],
        //width: "99%",
        //height: 300,
        //autoHeight: true,
        //autoHeight: true,
        collapsible: true,
        animCollapse: false,
        title: '假期项目值班安排',
        header: false,
        iconCls: 'icon-grid',
        initComponent: function () {
            var me = this;
            this.callParent(arguments);
        },// paging bar on the bottom
        bbar: Ext.create('Ext.PagingToolbar', {
            store: tab2mainStore,
            displayInfo: true,
            displayMsg: 'Displaying data {0} - {1} of {2}',
            emptyMsg: "No data to display"
        })
    });
    var mainGrid = new Ext.create('MainGrid');

    mainGrid.view.on('expandBody', function (rowNode, record, expandRow, eOpts) {
        displayInnerGrid(record.get('ObjectID'));
        setTimeout(function () {
            //heighinit();

        }, 1000);


    });

    mainGrid.view.on('collapsebody', function (rowNode, record, expandRow, eOpts) {
        destroyInnerGrid(record);
        setTimeout(function () {
            //heighinit();

        }, 1000);

    });

    //mainGrid.render('bb');

    //tab2结束
    //tab3开始
    
    tab3mainStore = Ext.create('Ext.data.ArrayStore', {
        model: 'tab2Model',
        autoLoad: true,
        proxy: {
            // load using script tags for cross domain, if the data in on the same domain as
            // this page, an HttpProxy would be better
            type: 'ajax',
            extraParams: { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val(), State: "Completed" },
            //type: 'json',
            url: '../../Ashx/GetCachetApplyWorkHighSpeed.ashx',
            reader: {
                //type: 'json' //返回数据类型为json格式
                root: 'data',
                totalProperty: 'totalCount'
            },
            // sends single sort as multi parameter
            simpleSortMode: true
        }
    });
    Ext.define('MainGrid2', {
        extend: 'Ext.grid.Panel',
        alias: 'widget.MainGrid',
        region: 'center',
        store: tab3mainStore,
        //autoHeight: true,
        columns: [
                {
                    id: 'ObjectID',
                    text: "用章事由",
                    dataIndex: 'Content',
                    flex: 1,
                    width: 100,
                    renderer: function (value, metaData, record, rowIndex, colIndex, store) {
                        return '<a href="../../Cachet/CachetApplyInfo.aspx?CachetApplyID=' + record.data.ObjectID + '">' + value + '</a>';
                    },
                    sortable: false
                }, {
                    text: "类型",
                    dataIndex: 'type',
                    width: 100,
                    //hidden: true,
                    sortable: true
                }, {
                    text: "时间",
                    dataIndex: 'createdate',
                    width: 250,
                    align: 'right',
                    sortable: true
                }, {
                    text: "当前审批人",
                    dataIndex: 'actor',
                    width: 250,
                    align: 'right',
                    sortable: true
                }
        ],
        selModel: {
            selType: 'cellmodel'
        },
        plugins: [{
            ptype: 'rowexpander',
            rowBodyTpl: [
                    '<div id="{ObjectID}">',
                    '</div>'
            ]
        }],
        //width: "99%",
        autoScroll: true,
        viewConfig: {
            style: { overflow: 'auto', overflowX: 'hidden' }
        },
        //height: 300,
        //autoHeight: true,
        collapsible: true,
        animCollapse: false,
        title: '假期项目值班安排',
        header: false,
        iconCls: 'icon-grid',
        initComponent: function () {
            var me = this;
            this.callParent(arguments);
        },// paging bar on the bottom
        bbar: Ext.create('Ext.PagingToolbar', {
            store: tab3mainStore,
            displayInfo: true,
            displayMsg: 'Displaying data {0} - {1} of {2}',
            emptyMsg: "No data to display"
        })
        ,
    });
    var mainGrid2 = new Ext.create('MainGrid2');

    mainGrid2.view.on('expandBody', function (rowNode, record, expandRow, eOpts) {
        displayInnerGrid(record.get('ObjectID'));
        setTimeout(function () {
            //heighinit();

        }, 1000);


    });

    mainGrid2.view.on('collapsebody', function (rowNode, record, expandRow, eOpts) {
        destroyInnerGrid(record);
        setTimeout(function () {
            //heighinit();

        }, 1000);

    });

    //mainGrid2.render('cc');
    //tab3结束
    var height = document.documentElement.clientHeight-70;
    //alert(height);
    tabs = Ext.widget('tabpanel', {
        renderTo: 'tabs1',
        width: "100%",
        height: height,
        activeTab: 0,
        autoHeight: false,
        //layout : 'border',
        border: false,
        region: 'center',
        defaults: {
            bodyPadding: 0
        },
        items: [{
            contentEl: 'aatab',
            title: '拟稿',
            items: grid,
            layout: 'border'
        }, {
            contentEl: 'bbtab',
            title: '正在审批',
            items: mainGrid,
            layout: 'border'
        }, {
            contentEl: 'cctab',
            title: '完成审批',
            items: mainGrid2,
            layout: 'border'
        }]
    });
    
});
function qingkong() {
    $("#txtDraftDes").val("");
    $("#ddlDraftType").val("-1");
}

function displaysearch(which) {
    if ($("#search").css("display") == "none") {
        $("#search").css("display","block");
        $(which).attr("src", "../../MenuCust/TelDemo/bottom.png");
    } else {
        $("#search").css("display", "none");
        $("#txtDraftDes").val("");
        $("#ddlDraftType").val("-1");
        $(which).attr("src", "../../MenuCust/TelDemo/top.png");
    }
    
}
function search() {
    if (tabs.getActiveTab().title == "拟稿") {
        //tab1store.loadPage(1);  txtDraftDes: type: -1
        
        tab1store.on('beforeload', function () {
            Ext.apply(tab1store.proxy.extraParams, { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val() });
        });
        tab1store.loadPage(1);
    } else if (tabs.getActiveTab().title == "正在审批") {
        tab2mainStore.on('beforeload', function () {
            Ext.apply(tab2mainStore.proxy.extraParams, { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val() });
        });
        tab2mainStore.load();
    } else if (tabs.getActiveTab().title == "完成审批") {
        tab3mainStore.on('beforeload', function () {
            Ext.apply(tab3mainStore.proxy.extraParams, { txtDraftDes: $("#txtDraftDes").val(), type: $("#ddlDraftType").val() });
        });
        tab3mainStore.load();
    }
    //mainStore.on('beforeload', function () {
    //    Ext.apply(mainStore.proxy.extraParams, { sysName: sysName });
    //});
    //mainStore.load();
}

2.html:

<!DOCTYPE html>

<html lang="zh-CN">

<head>

 
<meta http-equiv="X-UA-Compatible" content="IE=Edge">
    <meta charset="UTF-8" />
    <title>节假日值班安排</title>
    <script src="../Js/jquery.js"></script>
    <script src="../../Ext/ext-all.js"></script>
    <link href="../../Ext/resources/css/ext-all.css" rel="stylesheet" />
    <script src="../Js/tabs.js"></script>
    <script src="../Js/tab1.js"></script>
    <script src="../Js/PreviewPlugin.js"></script>
    <script src="../Js/tab2.js"></script>

    <style type="text/css">
        .btnHover {
            background-image: url(../../App_Themes/Glass/Images/backcolorImage.jpg);
            background-repeat: no-repeat;
        }

        .btnOut {
            background-image: none;
            text-decoration: none;
            text-align: center;
            padding-top: 2px;
        }

        .LinkbuttonCss {
            background: transparent url('../../App_Themes/Glass/Images/WebResource.png') no-repeat scroll top right;
            background-repeat: no-repeat;
            background-attachment: scroll;
            background-position: 100% -98px;
            border-collapse: separate;
            display: block;
            float: left;
            padding-bottom: 3px;
            padding-top: 1px;
            white-space: nowrap;
            text-decoration: none;
            cursor: pointer;
        }

        .LinkbuttonCss2 {
            border-collapse: separate;
            display: block;
            float: left;
            padding-bottom: 3px;
            padding-top: 1px;
            white-space: nowrap;
            text-decoration: none;
            cursor: pointer;
        }

        .spanCss {
            background: transparent url('../../App_Themes/Glass/Images/WebResource.png') no-repeat scroll top right;
            background-repeat: no-repeat;
            background-attachment: scroll;
            background-position: 0px -75.5px;
            border-collapse: separate;
            display: block;
            float: left;
            line-height: 1.3;
            padding-bottom: 3px;
            padding-left: 15px;
            padding-right: 3px;
            padding-top: 3px;
            white-space: nowrap;
            cursor: pointer;
        }

        .spanCss2 {
            border-collapse: separate;
            display: block;
            float: left;
            line-height: 1.3;
            padding-bottom: 3px;
            padding-left: 15px;
            padding-right: 3px;
            padding-top: 3px;
            white-space: nowrap;
            cursor: pointer;
        }

        .ellipsis {
            text-overflow: ellipsis;
            overflow: hidden;
            white-space: nowrap;
        }

        html, body {
            padding: 0px 0px 0px 0px;
            margin: 0px 0px 0px 0px;
            overflow: hidden; /*font-family: 微软雅黑;*/
            height: 100%;
            width: 100%;
            background-color: #E8EFF9;
        }

        .divselectmission {
            border-top-style: solid;
            border-top-color: #8DB2E3;
            border-top-width: 1px;
            border-left-style: solid;
            border-left-color: #8DB2E3;
            border-left-width: 1px;
            border-right-style: solid;
            border-right-color: #8DB2E3;
            border-right-width: 1px;
            border-bottom-color: #8DB2E3;
            border-bottom-style: solid;
            border-bottom-width: 1px;
            margin: 3px 3px 3px 3px;
            height: 27px;
            width: auto;
            background-image: url(../../MenuCust/TelDemo/daiban2.png);
        }

        .divmainContent {
            border-top-style: solid;
            border-top-color: #8DB2E3;
            border-top-width: 1px;
            border-left-style: solid;
            border-left-color: #8DB2E3;
            border-left-width: 1px;
            border-right-style: solid;
            border-right-color: #8DB2E3;
            border-right-width: 1px;
            border-bottom-color: #8DB2E3;
            border-bottom-style: solid;
            border-bottom-width: 1px;
            position: absolute;
            top: 33px;
            bottom: 3px;
            left: 3px;
            right: 3px;
            height: auto;
            width: auto;
            padding-top: 3px;
            background-image: url(../../MenuCust/TelDemo/daiban2.png);
        }

        .RadGridCss {
            position: absolute;
            top: 31px;
            bottom: 0px;
            height: auto;
            border-top-style: solid;
            border-top-color: #8DB2E3;
            border-top-width: 0px;
        }

        .RadGridCss1 {
        }

        .ExpandCollapseColumn {
            cursor: pointer;
        }
    </style>
    <style type="text/css">
        .list {
            padding-left: 16px;
            padding-bottom: 10px;
        }

            .list li {
                list-style: square;
                padding: 2px;
            }

        pre {
            font-size: 11px;
        }
    </style>
</head>
<body >
    <div id="selectmission" class="divselectmission">
        <div style="float: left; height: 100%; padding-left: 10px; padding-top: 8px; font-weight: 600; font-size: 12px; color: #000000">
            公章审批查询
        </div>
        <div style="float: right; height: 100%; padding-right: 6px; padding-top: 6px">
            <img id="imgbtn" alt="" src="../../MenuCust/TelDemo/top.png" style="cursor: hand" onclick="displaysearch(this)">
        </div>
    </div>
    <div id="search" style="display: none;">
        <div id="SearchDraft" style="display: block; background-color: #E8EFF9; padding-top: 4px; padding-bottom: 3px; padding-left: 6px; font-size: 12px;">
            <table>
                <tbody>
                    <tr>
                        <td style="text-align: right; padding-left: 3px;">
                            用章事由:
                        </td>
                        <td style="text-align: left;">
                            <input name="txtDraftDes" type="text" id="txtDraftDes" style="width: 200px;">
                        </td>
                        <td style="text-align: right; padding-left: 3px;">
                            类型:
                        </td>
                        <td style="text-align: left;">
                            <select name="ddlDraftType" id="ddlDraftType">
                                <option selected="selected" value="-1">全部</option>
                                <option value="1">股份</option>
                                <option value="2">集团</option>

                            </select>
                        </td>
                        <td>
                            <input type="button" name="btnQuery1" value="查询" onclick="search()"  id="btnQuery1" style="padding-top: 3px;">
                        </td>
                        <td>
                            <input type="button" id="button1" onclick="qingkong()" value="重置" style="padding-top: 3px;">
                        </td>
                        <td>
                            &nbsp;
                        </td>
                    </tr>
                </tbody>
            </table>
        </div>
    </div>
    <div id="tabs1">
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