JQuery UI之Autocomplete(4)多值輸入、遠程緩存與組合框

時間 2019-11-18

標籤 jquery autocomplete 多值輸入遠程緩存組合欄目 JQuery 简体版

原文原文鏈接

一、多值輸入javascript

首先加入相關的css和js文件，以及對應的HTML代碼以下：css

<link href="../css/jquery-ui.css" rel="stylesheet" />
<script type="text/javascript" src="../js/jquery-1.9.1.min.js" ></script>
<script type="text/javascript" src="../js/jquery-ui.js"  ></script>
<script type="text/javascript" src="../js/index.js"  ></script>

 <label for="language">搜索：</lable>
<input id="language" name="language" type="text">

對應的js代碼以下：html

var availableTags = ["ActionScript","AppleScript","Asp","BASIC","C","C++", "Clojure" ];
    function split( val ) {
        return val.split( /,\s*/ );
    }
    function extractLast( term ) {
        return split( term ).pop();
    }

    $( "#language" )
    // 當選擇一個條目時不離開文本域
    .bind( "keydown", function( event ) {
        if ( event.keyCode === $.ui.keyCode.TAB &&
                $( this ).data( "ui-autocomplete" ).menu.active ) {
            event.preventDefault();
        }
    })
    .autocomplete({
        minLength: 0,
        //本地數據
        /*    source: function( request, response ) {
            // 回到 autocomplete，可是提取最後的條目
            response( $.ui.autocomplete.filter(
                    availableTags, extractLast( request.term ) ) );
        },*/
        //遠程數據
        source: function( request, response ) {
            $.getJSON( "/Autocomplete.html", {
                term: extractLast( request.term )
            }, response );
        },
        search: function() {
            // 自定義最小長度
            var term = extractLast( this.value );
            if ( term.length < 1 ) {
                return false;
            }
        },
        focus: function() {
            // 防止在得到焦點時插入值
            return false;
        },
        select: function( event, ui ) {
            var terms = split( this.value );
            // 移除當前輸入
            terms.pop();
            // 添加被選項
            terms.push( ui.item.value );
            // 添加佔位符，在結尾添加逗號+空格
            terms.push( "" );
            this.value = terms.join( ", " );
            return false;
        }
    });

後臺的java代碼和上一篇同樣。前端

二、本地緩存數據，當用戶輸入字符時若是此字符沒有在本地緩存就去服務器拿，而後存到本地，當下一次有相同的字符輸入時直接取本地的數據。java

js代碼以下：jquery

   //爲了提升性能，這裏添加了一些本地緩存
    var cache = {};
    $( "#language" ).autocomplete({
        minLength: 0,
        source: function( request, response ) {
            var term = request.term;
            if ( term in cache ) {
                response( cache[ term ] );
                return;
            }

            $.getJSON(  "/Autocomplete.html", request, function( data, status, xhr ) {
                console.log(status);

                cache[ term ] = data;
                response( data );
            });
        }
    });

其前端和後臺程序和上文的同樣。編程

三、組合框緩存

首先映入css和js文件與上面的一致，對應的HTML代碼以下：服務器

<div class="ui-widget">
    <label>您喜歡的編程語言：</label> <select id="combobox">
        <option value="">請選擇...</option>
        <option value="ActionScript">ActionScript</option>
        <option value="AppleScript">AppleScript</option>
        <option value="Asp">Asp</option>
        <option value="BASIC">BASIC</option>
        <option value="C">C</option>
        <option value="C++">C++</option>
        <option value="Clojure">Clojure</option>
        <option value="COBOL">COBOL</option>
        <option value="ColdFusion">ColdFusion</option>
        <option value="Erlang">Erlang</option>
        <option value="Fortran">Fortran</option>
        <option value="Groovy">Groovy</option>
        <option value="Haskell">Haskell</option>
        <option value="Java">Java</option>
        <option value="JavaScript">JavaScript</option>
        <option value="Lisp">Lisp</option>
        <option value="Perl">Perl</option>
        <option value="PHP">PHP</option>
        <option value="Python">Python</option>
        <option value="Ruby">Ruby</option>
        <option value="Scala">Scala</option>
        <option value="Scheme">Scheme</option>
    </select>
</div>

js代碼以下:app

  (function( $ ) {
    $.widget( "custom.combobox", {
      _create: function() {
        this.wrapper = $( "<span>" )
          .addClass( "custom-combobox" )
          .insertAfter( this.element );
 
        this.element.hide();
        this._createAutocomplete();
        this._createShowAllButton();
      },
 
      _createAutocomplete: function() {
        var selected = this.element.children( ":selected" ),
          value = selected.val() ? selected.text() : "";
 
        this.input = $( "<input>" )
          .appendTo( this.wrapper )
          .val( value )
          .attr( "title", "" )
          .addClass( "custom-combobox-input ui-widget ui-widget-content ui-state-default ui-corner-left" )
          .autocomplete({
            delay: 0,
            minLength: 0,
            source: $.proxy( this, "_source" )
          })
          .tooltip({
            tooltipClass: "ui-state-highlight"
          });
 
        this._on( this.input, {
          autocompleteselect: function( event, ui ) {
            ui.item.option.selected = true;
            this._trigger( "select", event, {
              item: ui.item.option
            });
          },
 
          autocompletechange: "_removeIfInvalid"
        });
      },
 
      _createShowAllButton: function() {
        var input = this.input,
          wasOpen = false;
 
        $( "<a>" )
          .attr( "tabIndex", -1 )
          .attr( "title", "Show All Items" )
          .tooltip()
          .appendTo( this.wrapper )
          .button({
            icons: {
              primary: "ui-icon-triangle-1-s"
            },
            text: false
          })
          .removeClass( "ui-corner-all" )
          .addClass( "custom-combobox-toggle ui-corner-right" )
          .mousedown(function() {
            wasOpen = input.autocomplete( "widget" ).is( ":visible" );
          })
          .click(function() {
            input.focus();
 
            // 若是已經可見則關閉
            if ( wasOpen ) {
              return;
            }
 
            // 傳遞空字符串做爲搜索的值，顯示全部的結果
            input.autocomplete( "search", "" );
          });
      },
 
      _source: function( request, response ) {
        var matcher = new RegExp( $.ui.autocomplete.escapeRegex(request.term), "i" );
        response( this.element.children( "option" ).map(function() {
          var text = $( this ).text();
          if ( this.value && ( !request.term || matcher.test(text) ) )
            return {
              label: text,
              value: text,
              option: this
            };
        }) );
      },
 
      _removeIfInvalid: function( event, ui ) {
 
        // 選擇一項，不執行其餘動做
        if ( ui.item ) {
          return;
        }
 
        // 搜索一個匹配（不區分大小寫）
        var value = this.input.val(),
          valueLowerCase = value.toLowerCase(),
          valid = false;
        this.element.children( "option" ).each(function() {
          if ( $( this ).text().toLowerCase() === valueLowerCase ) {
            this.selected = valid = true;
            return false;
          }
        });
 
        // 找到一個匹配，不執行其餘動做
        if ( valid ) {
          return;
        }
 
        // 移除無效的值
        this.input
          .val( "" )
          .attr( "title", value + " didn't match any item" )
          .tooltip( "open" );
        this.element.val( "" );
        this._delay(function() {
          this.input.tooltip( "close" ).attr( "title", "" );
        }, 2500 );
        this.input.data( "ui-autocomplete" ).term = "";
      },
 
      _destroy: function() {
        this.wrapper.remove();
        this.element.show();
      }
    });
  })( jQuery );
 
  $(function() {
    $( "#combobox" ).combobox();
  });

最後，此方法不多用，由於對應的autocomplete能夠實現此功能。但爲了知識的完整性，這裏仍是能夠看一下。

最後還沒解決的問題：

$("#language").autocomplete({
        source: [ 'Chinese','English','Spanish','Russian','French','Japanese','Korean','German']，
         minLength : 0
    }).focus(function(){
        $(this).data("autocomplete").search($(this).val()); 
    });

此代碼的功能是當個人鼠標點擊輸入框時會自動把對應的選項列出了，可是本身測試時一直報以下錯誤。