小编Sag*_*gar的帖子

如何在java中将字符串"(123,456)"转换为-123456(负数)？

例如:

(123,456)= - 123456

123,456 = 123456

我使用了NumberFormat类但它只转换正数,而不是使用负数.

NumberFormat numberFormat = NumberFormat.getInstance();
try {
       System.out.println(" number formatted to " + numberFormat.parse("123,456"));
       System.out.println(" number formatted to " + numberFormat.parse("(123,456)"));
    } catch (ParseException e) {
           System.out.println("I couldn't parse your string!");
    }

输出:

数字格式为123456

我无法解析你的字符串!

这是我的代码来自http://jsfiddle.net/XUFUQ/1/

$(document).ready(function()
    {
        addElements();
    }
);

function addElements()
{
    $("#list1").empty().append(
        "<li id='item1' class='list1Items'>Item 1</li>"+
        "<li id='item2' class='list1Items'>Item 2</li>"+
        "<li id='item3' class='list1Items'>Item 3</li>"
    );
}

$(function() {
    // there's the gallery and the trash
    var $gallery = $( "#list1" ),
    $trash = $( "#list2" );

    // let the gallery items be draggable
    $( "li", $gallery ).draggable({
        cancel: "button", // these elements won't initiate dragging
        revert: "invalid", // when not dropped, the item will revert back to its initial position
        containment: …

我在做一个测验。并且所有选项都将在 for 循环中呈现。

预期行为：

当我点击一个选项时，如果它是错误的答案，那么它应该将背景颜色更改为红色并且它应该抖动。

下面是我正在尝试的代码。

import React, { Component } from "react";
import {
  View,
  Text,
  TouchableWithoutFeedback,
  Animated,
  Easing
} from "react-native";

class MCQOptions extends Component {
  state = {
    optionSelectedStatus: 0 // 0: unselected, 1: correct, -1: wrong
  };
  constructor() {
    super();
    this.animatedValue = new Animated.Value(0);
    this.shakeAnimValue = new Animated.Value(0);
  }

  onOptionSelected(i) {

    // this.props.showNextQuestion();

    var answer = this.props.answer;
    if (answer == i) {
      this.setState({ optionSelectedStatus: 1 });
      this.showCorrectAnimation();
    } else {
      this.setState({ optionSelectedStatus: -1 });
      this.showErrorAnimation();
    } …

这是我的xml代码......

<flow>
    <TaskID>100</TaskID>
    <TaskID>101</TaskID>
    <TaskID>102</TaskID>
    <TaskID>103</TaskID>    
</flow>

我想知道如何在java中的for循环中获取taskID值.请帮我...

我想在 svg 中选择前两个矩形并对它们应用过渡。我怎样才能做到这一点？

<svg width="1000px" height="500px" style="border:1px solid #AAA;"></svg>
<input type="button" value="Start" id="startTransition">

var dataArray = [5,10,20,30,40,50,60,70,80,90];
var baseLineYposition = 200;

var getY = function(value){
    return baseLineYposition - value;
};

var canvas = d3.select("svg");

var bars = canvas.selectAll("rect")
.data(dataArray)
.enter()
    .append("rect")
    .attr("width",30)
    .attr("height",function(d){return d;})
    .attr("x",function(d,i){return i * 50;})
    .attr("y",function(d,i){return getY(d);});


$(document).ready(function(){
    $("body").on("click","#startTransition",function(){

        var rect1 = d3.selectAll("rect")[0][0];
        var rect2 = d3.selectAll("rect")[0][1];

        rect1.transition().attr("x",200);
        rect2.transition().attr("x",300);
    });
});

此代码给出以下错误。

 rect1.transition is not a function