多條目資料庫展示
阿新 • • 發佈：2018-12-19
activityXML中的程式碼：
<ListView
android:id="@+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent"></ListView>
tt_itemXML中的程式碼：
<TextView android:id="@+id/title" android:layout_width="150dp" android:layout_height="wrap_content" android:layout_marginTop="8dp" android:maxLines="2" android:text="標題" android:layout_marginRight="150dp" android:textSize="17sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/date" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="16dp" android:text="日期" app:layout_constraintTop_toBottomOf="@+id/title" tools:layout_editor_absoluteX="0dp" tools:ignore="MissingConstraints" />
gg_itemXML中的程式碼：
<TextView android:id="@+id/title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginLeft="8dp" android:layout_marginTop="16dp" android:text="TextView" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/date" android:layout_width="wrap_content" android:layout_height="17dp" android:layout_marginTop="24dp" android:text="TextView" app:layout_constraintTop_toBottomOf="@+id/title" tools:ignore="MissingConstraints" tools:layout_editor_absoluteX="8dp" /> <ImageView android:id="@+id/image" android:layout_width="70dp" android:layout_height="70dp" android:layout_marginTop="8dp" android:layout_marginEnd="8dp" android:layout_marginRight="8dp" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintTop_toTopOf="parent" tools:srcCompat="@tools:sample/avatars" />
Bean中的程式碼：
public Result result; public Result getRestult() { return result; } class Result{ public List<Data> data; public List<Data> getData() { return data; } } class Data{ //判斷的資料 private final String panduan="頭條"; public String title; public String date; public String category; public String thumbnail_pic_s; public String utl; public String getTitle() { return title; } public String getDate() { return date; } public String getCategory() { return category; } public 大String getThumbnail_pic_s() { return thumbnail_pic_s; } public String getUtl() { return utl; } //進行判斷 public boolean panduan(){ return category.equals(panduan); } }
工具類中的程式碼：
//執行get請求 返回string結果
public static String zhixing(String lujing){
String result="";
try {
//定義ur地址
URL url=new URL(lujing);
//開啟連線
HttpURLConnection urlConnection= (HttpURLConnection) url.openConnection();
//請求方法
urlConnection.setRequestMethod("GET");
//讀取超時
urlConnection.setReadTimeout(5000);
//連線超時
urlConnection.setConnectTimeout(5000);
//獲取狀態值
int responseCode = urlConnection.getResponseCode();
if (responseCode==200){
result=zifu(urlConnection.getInputStream());
}
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
//位元組流轉換為字元流
private static String zifu(InputStream inputStream) throws IOException {
InputStreamReader inputStreamReader=new InputStreamReader(inputStream);
BufferedReader buff =new BufferedReader(inputStreamReader);
StringBuilder builder=new StringBuilder();
for (String imp=buff.readLine();imp!=null;imp=buff.readLine()){
builder.append(imp);
}
return builder.toString();
}
介面卡中的程式碼：
private List<Bean.Data> list;
private Context context;
private final int VIEW_COUNT=2;
private final int TT_VIEW=0;
private final int GN_VIEW=1;
//v子佈局的型別數量
@Override
public int getViewTypeCount() {
return VIEW_COUNT;
}
//判斷使用哪種子佈局
@Override
public int getItemViewType(int position) {
return getItem(position).ispan()? TT_VIEW:GN_VIEW;
}
public Mybase(Context context) {
this.context = context;
list=new ArrayList<>();
}
public void setList(List<Bean.Data> list) {
this.list = list;
notifyDataSetChanged();
}
@Override
public int getCount() {
return list.size();
}
@Override
public Bean.Data getItem(int position) {
return list.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){
//載入子佈局
convertView=LayoutInflater.from(context).inflate(
getItemViewType(position)==TT_VIEW?R.layout.tt_item:R.layout.gn_item
,parent,false);
holder=new ViewHolder(convertView);
convertView.setTag(holder);
}else{
holder= (ViewHolder) convertView.getTag();
}
holder.ccc(getItem(position));
return convertView;
}
class ViewHolder{
private TextView title;
private TextView date;
private ImageView image;
//獲取子佈局資源ID
public ViewHolder(View convertView) {
title= convertView.findViewById(R.id.title);
date=convertView.findViewById(R.id.date);
image=convertView.findViewById(R.id.image);
}
//寫入
public void ccc(Bean.Data item) {
title.setText(item.getTitle());
date.setText(item.getDate());
if (image!=null){
image.setImageResource(R.mipmap.ic_launcher);
}
}
}
資料庫中的程式碼：
public SqliteHelper(Context context) {
super(context, "User.db", null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table users (id integer primary key autoincrement," +
"title text," +
"date text," +
"category text)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
dao層的程式碼：
private SqliteHelper helper;
private SQLiteDatabase sb;
public Dao(Context context){
helper=new SqliteHelper(context);
sb=helper.getReadableDatabase();
}
public void zeng(Bean.Data data){
ContentValues values=new ContentValues();
values.put("title",data.getTitle());
values.put("date",data.getDate());
values.put("category",data.getCategory());
sb.insert("users",null,values);
}
public List<Bean.Data> cha(){
List<Bean.Data> list=new ArrayList<>();
Cursor query = sb.query("users", null, null, null, null, null, null);
while(query.moveToNext()){
String title = query.getString(query.getColumnIndex("title"));
String date = query.getString(query.getColumnIndex("date"));
String category = query.getString(query.getColumnIndex("category"));
Bean.Data data=new Bean.Data(title,date,category);
list.add(data);
}
return list;
}
public void shan(){
sb.delete("users",null,null);
}
Activity中的程式碼：
private ListView listView;
private Dao dao;
private Mybase mybase;
private String lujing1="http://result.eolinker.com/k2BaduF2a6caa275f395919a66ab1dfe4b584cc60685573?uri=tt";
private String lujing2="http://result.eolinker.com/k2BaduF2a6caa275f395919a66ab1dfe4b584cc60685573?uri=gn";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = findViewById(R.id.listview);
dao=new Dao(this);
mybase=new Mybase(this);
listView.setAdapter(mybase);
getdata();
}
private void getdata() {
@SuppressLint("StaticFieldLeak") AsyncTask<String,Void,List<Bean.Data>> asyncTask=new AsyncTask<String, Void, List<Bean.Data>>() {
@Override
protected List<Bean.Data> doInBackground(String... strings) {
List<Bean.Data> list=new ArrayList<>();
dao.shan();
for(String url : strings){
String jieguo = NetUtil.zhixing(url);
Bean bean = new Gson().fromJson(jieguo, Bean.class);
List<Bean.Data> data = bean.getResult().getData();
for (int i=0;i<data.size();i++){
String title = data.get(i).getTitle();
String date = data.get(i).getDate();
String category = data.get(i).getCategory();
Bean.Data dd=new Bean.Data(title,date,category);
dao.zeng(dd);
}
}
List<Bean.Data> cha = dao.cha();
//使集合裡的資料亂序
Collections.shuffle(cha);
return cha;
}
@Override
protected void onPostExecute(List<Bean.Data> data) {
mybase.setList(data);
}
}.execute(lujing1,lujing2);
}