您好,我是 android 编程新手。我想问一下如何使用意图将数据传递给另一个活动?我的情况是,我有一个 2 TextBox ,如果用户单击按钮,它应该被检索(文本)到数据库中。
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sqlcon = new SQLController(this);
firstname_et = (EditText) findViewById(R.id.fistname_et_id);
lastname_et = (EditText) findViewById(R.id.lastname_et_id);
addmem_btn = (Button) findViewById(R.id.addmem_btn_id);
table_layout = (TableLayout) findViewById(R.id.tableLayout1);
BuildTable();
addmem_btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
table_layout.removeAllViews();
String firstname = firstname_et.getText().toString();
String lastname = lastname_et.getText().toString();
firstname_et.setText("");
lastname_et.setText("");
// inserting data
sqlcon.open();
sqlcon.insertData(firstname, lastname);
BuildTable();
}
});
}
private void BuildTable() {
sqlcon.open();
Cursor c = sqlcon.readEntry();
int rows = c.getCount();
int cols = c.getColumnCount();
c.moveToFirst();
// outer for loop
for (int i = 0; i < rows; i++) {
TableRow row = new TableRow(this);
row.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.MATCH_PARENT,
TableRow.LayoutParams.WRAP_CONTENT));
// inner for loop
for (int j = 0; j < cols; j++) {
TextView tv = new TextView(this);
tv.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.WRAP_CONTENT,
TableRow.LayoutParams.WRAP_CONTENT));
tv.setBackgroundResource(R.drawable.abc_btn_borderless_material);
tv.setGravity(Gravity.CENTER);
tv.setTextSize(18);
tv.setPadding(0, 5, 0, 5);
tv.setText(c.getString(j));
row.addView(tv);
}
c.moveToNext();
table_layout.addView(row);
}
sqlcon.close();
}
SQLitecontroller.java
public SQLController(Context c) {
ourcontext = c;
}
public SQLController open() throws SQLException {
dbhelper = new DatabaseHelper(ourcontext);
database = dbhelper.getWritableDatabase();
return this;
}
public void close() {
dbhelper.close();
}
public void insertData(String name, String lname) {
// TODO Auto-generated method stub
ContentValues cv = new ContentValues();
cv.put(DatabaseHelper.MEMBER_FIRSTNAME, name);
cv.put(DatabaseHelper.MEMBER_LASTNAME, lname);
database.insert(DatabaseHelper.TABLE_MEMBER, null, cv);
}
public Cursor readEntry() {
// TODO Auto-generated method stub
String[] allColumns = new String[] { DatabaseHelper.MEMBER_ID, DatabaseHelper.MEMBER_FIRSTNAME,
DatabaseHelper.MEMBER_LASTNAME };
Cursor c = database.query(DatabaseHelper.TABLE_MEMBER, allColumns, null, null, null,
null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
数据库助手.java
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String TABLE_MEMBER = "member";
public static final String MEMBER_ID = "_id";
public static final String MEMBER_FIRSTNAME = "firstname";
public static final String MEMBER_LASTNAME = "lastname";
// DATABASE INFORMATION
static final String DB_NAME = "MEMBER.DB";
static final int DB_VERSION = 1;
public DatabaseHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
public static final String CREATE_TABLE = "create table " + TABLE_MEMBER
+ "(" + MEMBER_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ MEMBER_FIRSTNAME + " TEXT NOT NULL ," + MEMBER_LASTNAME
+ " TEXT NOT NULL);";
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_MEMBER);
onCreate(db);
}
}
请帮我。我已经尝试了很多次,但会产生错误,所以请帮助我。
在 TableView 中显示所有数据。