首先还是写一个XML界面:
"1.0" encoding="utf-8"?>
2.书写Java代码实现功能:
1 package com.example.zhoushasha.sqlitedatabasedemo;
2
3 import android.support.v7.app.AppCompatActivity;
4 import android.os.Bundle;
5 import android.app.Activity;
6 import android.content.Context;
7 import android.database.Cursor;
8 import android.os.Bundle;
9 import android.view.Menu;
10 import android.view.MenuItem;
11 import android.view.View;
12 import android.view.ViewGroup;
13 import android.widget.AdapterView;
14 import android.widget.BaseAdapter;
15 import android.widget.EditText;
16 import android.widget.ListView;
17 import android.widget.TextView;
18 import android.widget.Toast;
19 public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener {
20 private BooksDB mBooksDB;
21 private Cursor mCursor;
22 private EditText BookName;
23 private EditText BookAuthor;
24 private ListView BooksList;
25
26 private int BOOK_ID = 0;
27 protected final static int MENU_ADD = Menu.FIRST;
28 protected final static int MENU_DELETE = Menu.FIRST + 1;
29 protected final static int MENU_UPDATE = Menu.FIRST + 2;
30
31 public void onCreate(Bundle savedInstanceState) {
32 super.onCreate(savedInstanceState);
33 setContentView(R.layout.layout);
34 setUpViews();
35 }
36
37 public void setUpViews() {
38 mBooksDB = new BooksDB(this);
39 mCursor = mBooksDB.select();
40
41 BookName =(EditText)findViewById(R.id.bookname);
42 BookAuthor = (EditText) findViewById(R.id.author);
43 BooksList = (ListView) findViewById(R.id.bookslist);
44
45 BooksList.setAdapter(new BooksListAdapter(this, mCursor));
46 BooksList.setOnItemClickListener(this);
47 }
48
49 @Override
50 public boolean onCreateOptionsMenu(Menu menu) {
51 super.onCreateOptionsMenu(menu);
52
53 menu.add(Menu.NONE, MENU_ADD, 0, "ADD");
54 menu.add(Menu.NONE, MENU_DELETE, 0, "DELETE");
55 menu.add(Menu.NONE, MENU_DELETE, 0, "UPDATE");
56 return true;
57 }
58
59 public boolean onOptionsItemSelected(MenuItem item) {
60 super.onOptionsItemSelected(item);
61 switch (item.getItemId()) {
62 case MENU_ADD:
63 add();
64 break;
65 case MENU_DELETE:
66 delete();
67 break;
68 case MENU_UPDATE:
69 update();
70 break;
71 }
72 return true;
73 }
74
75 public void add() {
76 String bookname = BookName.getText().toString();
77 String author = BookAuthor.getText().toString();
78 //书名和作者都不能为空,或者退出
79 if (bookname.equals("") || author.equals("")) {
80 return;
81 }
82 mBooksDB.insert(bookname, author);
83 mCursor.requery();
84 BooksList.invalidateViews();
85 BookName.setText("");
86 BookAuthor.setText("");
87 Toast.makeText(this, "Add Successed!", Toast.LENGTH_SHORT).show();
88 }
89
90 public void delete() {
91 if (BOOK_ID == 0) {
92 return;
93 }
94 mBooksDB.delete(BOOK_ID);
95 mCursor.requery();
96 BooksList.invalidateViews();
97 BookName.setText("");
98 BookAuthor.setText("");
99 Toast.makeText(this, "Delete Successed!", Toast.LENGTH_SHORT).show();
100 }
101
102 public void update() {
103 String bookname = BookName.getText().toString();
104 String author = BookAuthor.getText().toString();
105 //书名和作者都不能为空,或者退出
106 if (bookname.equals("") || author.equals("")) {
107 return;
108 }
109 mBooksDB.update(BOOK_ID, bookname, author);
110 mCursor.requery();
111 BooksList.invalidateViews();
112 BookName.setText("");
113 BookAuthor.setText("");
114 Toast.makeText(this, "Update Successed!", Toast.LENGTH_SHORT).show();
115 }
116
117 @Override
118 public void onItemClick(AdapterView> parent, View view, int position, long id) {
119
120 mCursor.moveToPosition(position);
121 BOOK_ID = mCursor.getInt(0);
122 BookName.setText(mCursor.getString(1));
123 BookAuthor.setText(mCursor.getString(2));
124
125 }
126
127 public class BooksListAdapter extends BaseAdapter {
128 private Context mContext;
129 private Cursor mCursor;
130
131 public BooksListAdapter(Context context, Cursor cursor) {
132
133 mCOntext= context;
134 mCursor = cursor;
135 }
136
137 @Override
138 public int getCount() {
139 return mCursor.getCount();
140 }
141
142 @Override
143 public Object getItem(int position) {
144 return null;
145 }
146
147 @Override
148 public long getItemId(int position) {
149 return 0;
150 }
151
152 @Override
153 public View getView(int position, View convertView, ViewGroup parent) {
154 TextView mTextView = new TextView(mContext);
155 mCursor.moveToPosition(position);
156 mTextView.setText(mCursor.getString(1) + "___" + mCursor.getString(2));
157 return mTextView;
158 }
159
160 }
161 }
3.创建一个新类bookDB.java类继承:
package com.example.zhoushasha.sqlitedatabasedemo;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class BooksDB extends SQLiteOpenHelper {
private final static String DATABASE_NAME = "BOOKS.db";
private final static int DATABASE_VERSION = 1;
private final static String TABLE_NAME = "books_table";
public final static String BOOK_ID = "book_id";
public final static String BOOK_NAME = "book_name";
public final static String BOOK_AUTHOR = "book_author";
public BooksDB(Context context) {
// TODO Auto-generated constructor stub
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
//创建table
@Override
public void onCreate(SQLiteDatabase db) {
String sql = "CREATE TABLE " + TABLE_NAME + " (" + BOOK_ID
+ " INTEGER primary key autoincrement, " + BOOK_NAME + " text, "+ BOOK_AUTHOR +" text);";
db.execSQL(sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
String sql = "DROP TABLE IF EXISTS " + TABLE_NAME;
db.execSQL(sql);
onCreate(db);
}
public Cursor select() {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db
.query(TABLE_NAME, null, null, null, null, null, null);
return cursor;
}
//增加操作
public long insert(String bookname,String author)
{
SQLiteDatabase db = this.getWritableDatabase();
/* ContentValues */
ContentValues cv = new ContentValues();
cv.put(BOOK_NAME, bookname);
cv.put(BOOK_AUTHOR, author);
long row = db.insert(TABLE_NAME, null, cv);
return row;
}
//删除操作
public void delete(int id)
{
SQLiteDatabase db = this.getWritableDatabase();
String where = BOOK_ID + " = ?";
String[] whereValue ={ Integer.toString(id) };
db.delete(TABLE_NAME, where, whereValue);
}
//修改操作
public void update(int id, String bookname,String author)
{
SQLiteDatabase db = this.getWritableDatabase();
String where = BOOK_ID + " = ?";
String[] whereValue = { Integer.toString(id) };
ContentValues cv = new ContentValues();
cv.put(BOOK_NAME, bookname);
cv.put(BOOK_AUTHOR, author);
db.update(TABLE_NAME, cv, where, whereValue);
}
}