做RPG游戏的时候会有剧情对，中英文混搭，要求打字效果，一个字一个字的往出蹦。

先看一下xml文件

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1. <?xml version="1.0" encoding="UTF-8"?>
3. <plist version="1.0">
4. <talk anchor="0" icon="talk/icon.png" name="路人甲：" content=" 听说他已经30了。"/>
5. <talk anchor="1" icon="talk/icon.png" name="路人乙：" content=" 是啊！都30了还叫to3（奔三），装嫩呢！"/>
6. <talk anchor="0" icon="talk/icon.png" name="路人甲：" content=" 哈哈哈……"/>
7. </plist>

anchor：对齐方式 0左 1右

创建一个对话映射的节点TalkNode

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1. class TalkNode
2. {
3. public:
4. bool anchor;
5. std::string icon;
6. std::string name;
7. std::string content;
8. void init(TiXmlNode *node);
9. bool getAnchor(){return anchor;};
10. const char* getIcon(){returnicon.c_str();};
11. const char* getName(){returnname.c_str();};
12. const char* getContent(){returncontent.c_str();};
13. std::string getContentByLength(intlength);
14. int contentLeght;
15. int getContentLength();
16. };

再看TalkNode的实现

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1. voidTalkNode::init(TiXmlNode *node)
2. {
3. TiXmlElement *element =node->ToElement();
5. int intValue;
6. if(element->QueryIntAttribute("anchor", &intValue) ==TIXML_SUCCESS)
7. {
8. anchor = intValue;
9. }
10. else
11. {
12. anchor = false;
13. }
15. name =element->Attribute("name");
16. icon =element->Attribute("icon");
17. content =element->Attribute("content");
18. contentLeght = 0;
20. int length = content.length();
21. int i = 0;
22. while(i < length)
23. {
24. char ch = getContent()[i];
25. //重点在这里
26. //中文在ASCII码中是-127~0
27. if (ch > -127 && ch< 0)
28. {
29. //这里为什么+＝3呢
30. //因为一个中文占3个字节
31. i+=3;
32. }
33. else
34. {
35. i++;
36. }
37. contentLeght++;
38. }
39. }
40. //获取内容的总长度
41. int TalkNode::getContentLength()
42. {
43. return contentLeght;
44. }
46. //返回所需长度的字符串
47. std::string TalkNode::getContentByLength(int length)
48. {
49. if (length >= contentLeght)
50. {
51. return getContent();
52. }
53. int i = 0;
54. int index = 0;
55. while(index < length)
56. {
57. char ch = getContent()[i];
58. //这里上面说过了
59. if (ch > -127 && ch < 0)
60. {
61. i+=3;
62. }
63. else
64. {
65. i++;
66. }
67. index++;
68. }
70. //截取strng
71. std::string str = content.substr(0, i);
72. return str;
73. }

有同学会问TiXmlElement是哪来的？ to3是用的tinyxml解析xml，度娘可以找的到。

下面看一下to3的读取xml的函数

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1. std::vector <TalkNode*> talkList;
2. void Talking::readXml(const char *filename)
3. {
4. unsigned long filesize;
5. const char *path = CCFileUtils::sharedFileUtils()->fullPathFromRelativePath(filename);
6. char *buffer = (char *)CCFileUtils::sharedFileUtils()->getFileData(path, "rb", &filesize);
9. if (buffer == NULL)
10. {
11. return;
12. }
14. TiXmlDocument doc;
15. doc.Parse(buffer);
16. TiXmlNode *root = doc.FirstChild("plist");
18. if (root)
19. {
20. TiXmlElement *element = root->ToElement();
21. for (TiXmlNode* entityNode = root->FirstChild(); entityNode; entityNode = entityNode->NextSibling())
22. {
23. TalkNode *node= new TalkNode();
24. node->init(entityNode);
25. talkList.push_back(node);
26. }
27. talkCount = talkList.size();
28. }
29. }

到这里就可以实现打字效果了，但我们还得自动换行，这个cocos2d-x的CCLabelTTF有提供这个API

CCLabelTTF * CCLabelTTF::create(const char *string, const char *fontName, float fontSize, const CCSize& dimensions, CCTextAlignment hAlignment);

string：内容

fontName：字体

fontSize：字号

dimensions：显示框

hAlignment：对齐方式

最后在逻辑循环里更新你的CCLabelTTF字符串就可以了

[cpp] view plaincopy

1. void Talking::logic(float cTime)
2. {
3. TalkNode* node = (TalkNode*)talkList[talkIndex];
4. if (wordCount > node->getContentLength())
5. {
6. return;
7. }
10. wordCount++;
11. CCLabelTTF* label = (CCLabelTTF*)this->getChildByTag(kTalkingLabelTag);
12. label->setString(node->getContentByLength(wordCount).c_str());
13. }

再加上点击屏幕显示全部内容

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1. bool Talking::ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent)
2. {
3. TalkNode* node = (TalkNode*)talkList[talkIndex];
4. if (wordCount < node->getContentLength())
5. {
6. wordCount = node->getContentLength();
7. }
9. return true;
10. }

附上效果图两张