安卓编程题

article/2025/8/22 22:53:24

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:paddingBottom="20dp"><Buttonandroid:id="@+id/btn_one"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_alignParentBottom="true"android:text="按钮1" /><Buttonandroid:id="@+id/btn_two"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerHorizontal="true"android:layout_marginTop="260dp"android:text="按钮2" /><Buttonandroid:id="@+id/btn_three"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_alignBottom="@id/btn_two"android:layout_marginBottom="100dp"android:layout_toRightOf="@id/btn_two"android:text="按钮3" />
</RelativeLayout>

隐式

这道题考的是查询，也可能考其他的功能（增删改查）

@Overridepublic void onClick(View v) {String name, phone;SQLiteDatabase db;ContentValues values;switch (v.getId()) {case R.id.btn_query: //查询数据db = myHelper.getReadableDatabase();Cursor cursor = db.query("information", null, null, null, null,null, null);if (cursor.getCount() == 0) {mTvShow.setText("");Toast.makeText(this, "没有数据", Toast.LENGTH_SHORT).show();} else {cursor.moveToFirst();mTvShow.setText("Name :  " + cursor.getString(1) +"  ；Tel :  " + cursor.getString(2));}while (cursor.moveToNext()) {mTvShow.append("\n" + "Name :  " + cursor.getString(1) +"  ；Tel :  " + cursor.getString(2));}cursor.close();db.close();break;case R.id.btn_add: //添加数据name = mEtName.getText().toString();phone = mEtPhone.getText().toString();db = myHelper.getWritableDatabase();//获取可读写SQLiteDatabse对象values = new ContentValues();        //创建ContentValues对象values.put("name", name);             //将数据添加到ContentValues对象values.put("phone", phone);db.insert("information", null, values);Toast.makeText(this, "信息已添加", Toast.LENGTH_SHORT).show();db.close();break;case R.id.btn_update: //修改数据db = myHelper.getWritableDatabase();values = new ContentValues();       // 要修改的数据values.put("phone", phone = mEtPhone.getText().toString());db.update("information", values, "name=?",new String[]{mEtName.getText().toString()}); // 更新并得到行数Toast.makeText(this, "信息已修改", Toast.LENGTH_SHORT).show();db.close();break;case R.id.btn_delete: //删除数据db = myHelper.getWritableDatabase();db.delete("information", null, null);Toast.makeText(this, "信息已删除", Toast.LENGTH_SHORT).show();mTvShow.setText("");db.close();break;}}