12、json、GridView、缓存

1.解析json数据：

public class PhotosData {

public int retcode;

public PhotosInfo data;

public class PhotosInfo {

public String title;

public ArrayList<PhotoInfo> news;

}

public class PhotoInfo {

public String id;

public String listimage;

public String pubdate;

public String title;

public String type;

public String url;

}

}

[/code]
2.布局：

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent" >

<ListView

android:id="@+id/lv_photo"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:cacheColorHint="#fff"

android:divider="@null" />

<GridView

android:id="@+id/gv_photo"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:numColumns="2"

android:visibility="gone" />

</FrameLayout>

[/code]使用同一个子布局，同一个adapter

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:orientation="vertical" >

<LinearLayout

android:layout_width="match_parent"

    android:layout_height="wrap_content"

android:layout_margin="10dp"

android:background="@drawable/pic_list_item_bg"

android:gravity="center"

    android:orientation="vertical" >

<ImageView

android:id="@+id/iv_pic"

android:layout_width="match_parent"

android:layout_height="180dp"

android:scaleType="centerCrop"

android:src="@drawable/news_pic_default" />

<TextView

android:id="@+id/tv_title"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:padding="10dp"

android:text="标题"

android:singleLine="true"

android:textColor="#000"

android:textSize="22sp" />

</LinearLayout>

</LinearLayout>

[/code]3.菜单详情页—组图

public static final String PHOTOS_URL = SERVER_URL

+ "/photos/photos_1.json";// 获取组图信息的接口

[/code]

public class PhotoMenuDetailPager extends BaseMenuDetailPager {

private ListView lvPhoto;

private GridView gvPhoto;

private ArrayList<PhotoInfo> mPhotoList;

private PhotoAdapter mAdapter;

private ImageButton btnPhoto;

public PhotoMenuDetailPager(Activity activity, ImageButton btnPhoto) {

super(activity);

this.btnPhoto = btnPhoto;

//这样就把imagebutton传了过来，好方法。在构造函数里传

btnPhoto.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

changeDisplay();

}

});

}

@Override

public View initViews() {

View view = View.inflate(mActivity, R.layout.menu_photo_pager, null);

lvPhoto = (ListView) view.findViewById(R.id.lv_photo);

gvPhoto = (GridView) view.findViewById(R.id.gv_photo);

return view;

}

@Override

public void initData() {

String cache = CacheUtils

.getCache(GlobalContants.PHOTOS_URL, mActivity);

if (!TextUtils.isEmpty(cache)) {

}

getDataFromServer();

}

private void getDataFromServer() {

HttpUtils utils = new HttpUtils();

utils.send(HttpMethod.GET, GlobalContants.PHOTOS_URL,

new RequestCallBack<String>() {

@Override

public void onSuccess(ResponseInfo<String> responseInfo) {

String result = (String) responseInfo.result;

parseData(result);

// 设置缓存

CacheUtils.setCache(GlobalContants.PHOTOS_URL, result,

mActivity);

}

@Override

public void onFailure(HttpException error, String msg) {

Toast.makeText(mActivity, msg, Toast.LENGTH_SHORT)

.show();

error.printStackTrace();

}

});

}

protected void parseData(String result) {

Gson gson = new Gson();

PhotosData data = gson.fromJson(result, PhotosData.class);

mPhotoList = data.data.news;// 获取组图列表集合

if (mPhotoList != null) {

mAdapter = new PhotoAdapter();

lvPhoto.setAdapter(mAdapter);

gvPhoto.setAdapter(mAdapter);

}

}

class PhotoAdapter extends BaseAdapter {

private BitmapUtils utils;

public PhotoAdapter() {

utils = new BitmapUtils(mActivity);

utils.configDefaultLoadingImage(R.drawable.news_pic_default);

}

@Override

public int getCount() {

return mPhotoList.size();

}

@Override

public PhotoInfo getItem(int position) {

return mPhotoList.get(position);

}

@Override

public long getItemId(int position) {

return position;

}

@Override

public View getView(int position, View convertView, ViewGroup parent) {

ViewHolder holder;

if (convertView == null) {

convertView = View.inflate(mActivity, R.layout.list_photo_item,

null);

holder = new ViewHolder();

holder.tvTitle = (TextView) convertView

.findViewById(R.id.tv_title);

holder.ivPic = (ImageView) convertView

.findViewById(R.id.iv_pic);

convertView.setTag(holder);

} else {

holder = (ViewHolder) convertView.getTag();

}

PhotoInfo item = getItem(position);

holder.tvTitle.setText(item.title);

utils.display(holder.ivPic, item.listimage);

return convertView;

}

}

static class ViewHolder {

public TextView tvTitle;

public ImageView ivPic;

}

private boolean isListDisplay = true;// 是否是列表展示

/**

* 切换展现方式

*/

private void changeDisplay() {

if (isListDisplay) {

isListDisplay = false;

lvPhoto.setVisibility(View.GONE);

gvPhoto.setVisibility(View.VISIBLE);

btnPhoto.setImageResource(R.drawable.icon_pic_list_type);

} else {

isListDisplay = true;

lvPhoto.setVisibility(View.VISIBLE);

gvPhoto.setVisibility(View.GONE);

btnPhoto.setImageResource(R.drawable.icon_pic_grid_type);

}

}

}

[/code]4.其他在basepager里添加这样一个按钮，并findviewbyid出来，因为菜单是新闻中心里才有的，组图是菜单里的一项

<ImageButton

android:id="@+id/btn_photo"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentRight="true"

android:layout_centerVertical="true"

android:layout_marginRight="5dp"

android:background="@null"

android:src="@drawable/icon_pic_grid_type"

    android:visibility="gone" />

[/code]新闻中心页面setCurrentMenuDetailPager中

if (pager instanceof PhotoMenuDetailPager) {

btnPhoto.setVisibility(View.VISIBLE);

} else {

btnPhoto.setVisibility(View.GONE);

}

[/code]

来自为知笔记(Wiz)