IOS development-XML parsing and pull-down refresh to pull and load more sharing, iosxml

IOS development-XML parsing and pull-down refresh to pull and load more sharing, iosxml
XML parsing for IOS development

　　

1. XML format

<? Xml version = "1.0" encoding = "UTF-8"?> Indicates the XML file version. The internal text is encoded.

<Root> indicates the root node.

<CityName> Beijing </CityName> is a node. CityName indicates the end name and Beijing node value.

<Item key = "1" value = "A"> </Item> key = "1" is the node attribute, key attribute name, and "1" attribute value.

Note: The XML structure is understood as a layer-by-layer nested tree structure.

<? Xml version = "1.0" encoding = "UTF-8"?> <Root> <systemConfig> <CityName> Beijing </CityName> <CityCode> 201 </CityCode> <ParentCityCode> 0 </ParentCityCode> <areaCode> 010 </areaCode> <AgreementUrl> </AgreementUrl> <IntentionLevel> <Item key = "1" value = "A"> </Item> <Item key = "2" value = "B"> </ item> <Item key = "3" value = "C"> </Item> </IntentionLevel> <ComeChannel> <Item key = "1" value = "newspaper"> </Item> <Item key = "2" value = "magazine"> </Item> </ComeChannel> <BuyCarBudget> <Item key = "1" value = "40-50 thousand"> </Item> <Item key = "2" value = "50-60"> </Item> </BuyCarBudget> <IntentionColor> <Item key = "1" value =" red "> </Item> <Item key =" 2 "value =" yellow "> </Item> </IntentionColor> </systemConfig> </root>

2. How to use the open-source GData library for XML Parsing

Common XML parsing Methods

(1) unix-libxml2 C interface

(2) The XML parsing library provided by NSXMLParser UI is troublesome to use.

(3) GData development by google

2.1 Configuration

2.2 Use of GData

// 1. load and parse the XML file NSString * path = [[NSBundle mainBundle] pathForResource: @ "xml.txt" ofType: nil]; NSData * data = [[NSData alloc] initWithContentsOfFile: path]; // GDataXMLDocument indicates the XML Document Object // initWithData is initialized using NSData, that is, parsing GDataXMLDocument * doc = [[GDataXMLDocument alloc] initWithData: data options: 0 error: nil]; // 2. obtain the path of the specified node XPath // CityName:/root/systemConfig/CityName NSArray * array = [doc nodesForXPath: @ "/root/systemConfig/CityName" error: nil]; // CityName GDataXMLElement * element = [array firstObject]; NSLog (@ "name = % @ value = % @", element. name, element. stringValue); // 3. get the attribute NSArray * items = [doc nodesForXPath: @ "/root/systemConfig/ComeChannel/Item" error: nil]; GDataXMLElement * item = [items firstObject]; // obtain attributes. The attributes are represented by GDataXMLElement for (GDataXMLElement * attr in item. attributes) {NSLog (@ "a-name = % @ avalue = % @", attr. name, attr. stringValue);} // 4. get all nodes with the specified name (regardless of location) // XPath Syntax: // Item NSArray * allItem = [doc nodesForXPath: @ "// Item" error: nil]; for (GDataXMLElement * e in allItem) {NSLog (@ "name = % @", e. name);} // 5. obtain the attributes of all specified names (regardless of the node) // XPath Syntax: // @ value NSArray * allValue = [doc nodesForXPath: @ "// @ value" error: nil]; for (GDataXMLElement * e in allValue) {NSLog (@ "value = % @", e. stringValue);} // 6. traverse XML files layer by layer // obtain the root node GDataXMLElement * root = doc. rootElement; // obtain the subnode // root. children // obtain the number of subnodes // root. childCount // obtain the child node with the specified name // root elementsForName: <# (NSString *) #>

 

IOS development pull-down refresh and pull more

Common implementation methods of pull-down refresh

(1) UIRefreshControl

(2) EGOTableViewRefresh

(3) AH3DPullRefresh

(4) MJRefresh

(5) self-implementation

The specific refresh method will be discussed later!