Gson解析Json文件,实现案例

1、首先先看json文件,这个json并不算复杂分三层

2、分析完json文件我们开始创建Bean,json其实可以自动生成,由于我用的版本较低的eclipse所以手动敲的,注释不全见谅
public class PersonsBean {
// 属性私有化,参数名一定要与json文件保持一致
private String info;
private String status;
private DataBean data;

// set、get方法
public String getInfo() {
	return info;
}

public void setInfo(String info) {
	this.info = info;
}

public String getStatus() {
	return status;
}

public void setStatus(String status) {
	this.status = status;
}

public DataBean getData() {
	return data;
}

public void setData(DataBean data) {
	this.data = data;
}

// 静态内部类
public static class DataBean {
	private String count;
	private String type;
	private List phones;

	public String getCount() {
		return count;
	}

	public void setCount(String count) {
		this.count = count;
	}

	public String getType() {
		return type;
	}

	public void setType(String type) {
		this.type = type;
	}

	public List getPhones() {
		return phones;
	}

	public void setPhones(List phones) {
		this.phones = phones;
	}
	// 静态内部类
	public static class PhonesBean {
		private String brand;
		private String name;
		private String price;

		public String getBrand() {
			return brand;
		}

		public void setBrand(String brand) {
			this.brand = brand;
		}

		public String getName() {
			return name;
		}

		public void setName(String name) {
			this.name = name;
		}

		public String getPrice() {
			return price;
		}

		public void setPrice(String price) {
			this.price = price;
		}

	}
}

}
3、我用的Fragment写的所以下面是Fragment,和activity不同的就是获取上下文
布局很简单相信一看就知道只有一个ListView控件

public class AFragment extends Fragment {
private List list;

@Override
public View onCreateView(LayoutInflater inflater,
		@Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
	View view = View.inflate(getActivity(), R.layout.fragment1, null);
	ListView listView = (ListView) view.findViewById(R.id.listView_f1);
	initDatas();
	//设置适配器
	AFAdapter afAdapter = new AFAdapter(list, getActivity());
	listView.setAdapter(afAdapter);
	return view;
}

private void initDatas() {
	// 从sd卡中读取json文件并Gson解析
	File file = new File(Environment.getExternalStorageDirectory(),
			"persons.json");
	// 读取文件
	try {
		BufferedReader bufferedReader = new BufferedReader(
				new InputStreamReader(new FileInputStream(file)));
		// 创建StringBuffer
		StringBuffer stringBuffer = new StringBuffer();
		String temp = "";
		try {
			// 一行一行的读
			while ((temp = bufferedReader.readLine()) != null) {
				stringBuffer.append(temp);
			}
			String presonsString = stringBuffer.toString();
			// 解析,创建Gson,需要导入gson的jar包
			Gson gson = new Gson();
			PersonsBean fromJson = gson.fromJson(presonsString,
					PersonsBean.class);
			// 得到list数据
			list = fromJson.getData().getPhones();

		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	} catch (FileNotFoundException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
}

}
适配器中的代码,都是一样的这里我们做了优化
public class AFAdapter extends BaseAdapter {
private List list;
private Context mContext;

public AFAdapter(List list, Context mContext) {
	super();
	this.list = list;
	this.mContext = mContext;
}

@Override
public int getCount() {
	// TODO Auto-generated method stub
	return list.size();
}

@Override
public Object getItem(int position) {
	// TODO Auto-generated method stub
	return list.get(position);
}

@Override
public long getItemId(int position) {
	// TODO Auto-generated method stub
	return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
	ViewHolder holder;
	if (convertView == null) {
		convertView = View.inflate(mContext, R.layout.a_l_item, null);
		holder = new ViewHolder();
		holder.brand = (TextView) convertView.findViewById(R.id.brand_al);
		holder.name = (TextView) convertView.findViewById(R.id.name_al);
		holder.price = (TextView) convertView.findViewById(R.id.price_al);
		convertView.setTag(holder);
	} else {
		holder = (ViewHolder) convertView.getTag();
	}
	// 设置内容
	PhonesBean phonesBean = list.get(position);
	holder.brand.setText(phonesBean.getBrand());
	holder.name.setText(phonesBean.getName());
	holder.price.setText(phonesBean.getPrice());
	return convertView;
}

class ViewHolder {
	TextView brand, name, price;
}

}