Hoc GridView cơ bản trong android

Code file MainActivity.java

package com.example.macbookpro.dtsondcgridviewtext;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.GridView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    GridView grvDienThoai;
    String arrDt[] = {"Iphone 5","Iphone 5s", "Iphone 6", "Iphone 6s", "Samsung s6", "Samsung s7","Samsung note 4", "Samsung note 5","Htc m9","Htc m10"};
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // anh xa        grvDienThoai = (GridView) findViewById(R.id.gridViewDienThoai);
        final ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,arrDt);
        grvDienThoai.setAdapter(adapter);

        // thiet lap su kien click tren GridView        grvDienThoai.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(MainActivity.this,"Ban dang chon: "+arrDt[position],Toast.LENGTH_LONG).show();
            }
        });
    }
}

Code file xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:orientation="vertical"    tools:context="com.example.macbookpro.dtsondcgridviewtext.MainActivity">

    <GridView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:numColumns="3"        android:id="@+id/gridViewDienThoai" />
</LinearLayout>

AutoCompleteTextview với dữ liệu cố định chứa trong file xml

Code MainActivity

package com.example.macbookpro.hocautocompletetextview;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    TextView txtTen,txtThongTin;
    AutoCompleteTextView autoNoiSinh;
    String [] arrTinhThanh;
    ArrayAdapter<String> adapter;

    Button btnXacNhan;
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        addControls();
        addEvents();
    }

    private void addEvents() {
        btnXacNhan.setOnClickListener(new View.OnClickListener() {
            @Override            public void onClick(View v) {
                xuLyXacNhan();
            }
        });
    }

    private void xuLyXacNhan() {
        txtThongTin.setText(txtTen.getText().toString()+"\n"+autoNoiSinh.getText());
    }

    private void addControls() {
        // anh xa cac control        txtTen = (TextView) findViewById(R.id.txtHoTen);
        txtThongTin = (TextView) findViewById(R.id.txtThongtin);
        autoNoiSinh = (AutoCompleteTextView) findViewById(R.id.autotxtNoiSinh);
        btnXacNhan = (Button) findViewById(R.id.btnXacNhan);
        // lay du lieu tu file xml do vao array        arrTinhThanh = getResources().getStringArray(R.array.arrTinhThanh);
        //tao adapter        adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,arrTinhThanh);
        // thiet lap adapter cho autoCompleteTextview        autoNoiSinh.setAdapter(adapter);
    }
}

Code Xml giao dien

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:orientation="vertical"    tools:context="com.example.macbookpro.hocautocompletetextview.MainActivity">

    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceLarge"        android:text="Ho ten"        android:id="@+id/textView" />

    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/txtHoTen" />

    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceLarge"        android:text="Noi sinh"        android:id="@+id/textView2" />

    <AutoCompleteTextView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:completionThreshold="1"        android:id="@+id/autotxtNoiSinh" />

    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceLarge"        android:id="@+id/txtThongtin"        android:layout_gravity="center_horizontal"        android:hint="Thong tin hien thi o day nay" />

    <Button        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="Xac Nhan"        android:id="@+id/btnXacNhan"        android:layout_gravity="center_horizontal" />
</LinearLayout>

Code Xml dữ liệu tỉnh thành trong file string.xml


<resources>
    <string name="app_name">HocAutoCompleteTextview</string>
    <string-array name="arrTinhThanh">
        <item>Bà Rịa - Vũng Tàu</item>
        <item>Bắc Giang</item>
        <item>Bắc Kạn</item>
        <item>Bạc Liêu</item>
        <item>Bắc Ninh</item>
        <item>Bến Tre</item>
        <item>Bình Định</item>
        <item>Bình Dương</item>


    </string-array>
</resources>

Tìm hiểu về Spinner trong android

Spinner là gì

Nếu bạn đã từng lập trình vb.net, C Sharp thì Spinner giống như ComboBox. Trong Java ta có JComboBox cũng tương tự nhu spinner

Trong android cách sử dụng Spinner và ListView gần như nhau, Spinner chỉ khác ListView là bạn phải set Resource cho DropDownView, xem code bên dưới để hiểu hơn về spinner

Code Clas MainActivity

package com.example.macbookpro.dtsondcspinner2;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    Spinner spn;
    String arr[] = {"Cocacola", "Pepsi","Redbull","C2","Other"};
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //==== anh xa        spn = (Spinner) findViewById(R.id.spinnerNuocUong);

        // === tao ArrayAdapter        ArrayAdapter<String > adapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,arr);
        // thiet lap Resource cho  DropDown        adapter.setDropDownViewResource(android.R.layout.simple_list_item_single_choice);
        // gan adapter cho spinner        spn.setAdapter(adapter);

        //=== Thiet lap su kien select tren cac Item cua spinner        spn.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            //Khi select vao 1 Item bat ky            @Override            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                String nuocUong = arr[position];
                Toast.makeText(MainActivity.this,"Ban vua chon nuoc uong: "+nuocUong,Toast.LENGTH_SHORT).show();
            }
            // khi Khong select vao bat ky Item nao            @Override            public void onNothingSelected(AdapterView<?> parent) {
                Toast.makeText(MainActivity.this,"Ban chua chon nuoc uong!",Toast.LENGTH_SHORT).show();
            }
        });
    }
}

Code Xml giao diện

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:orientation="vertical"    tools:context="com.example.macbookpro.dtsondcspinner2.MainActivity">

    <TextView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceLarge"        android:text="DANH SACH NUOC UONG"        android:background="#1941c6"        android:textColor="#FF0000"        android:gravity="center"        android:id="@+id/textView"        android:layout_gravity="center_horizontal" />

    <Spinner        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/spinnerNuocUong"        android:layout_gravity="center_horizontal" />
</LinearLayout>

ưng dụng quản lý tính tiền bán sách đơn giản - lập trinh android

 

Code Class KhachHang

package com.example.macbookpro.dtsondctinhtienbansach;
public class KhachHang {
    public String tenKh;
    public Integer slMua;
    public Boolean laVip;
    public final Integer GiaBan=20000;

    public KhachHang() {
    }

    public KhachHang(Boolean laVip, Integer slMua, String tenKh) {
        this.laVip = laVip;
        this.slMua = slMua;
        this.tenKh = tenKh;
    }

    public Integer getGiaBan() {
        return GiaBan;
    }

    public Boolean getLaVip() {
        return laVip;
    }

    public Integer getSlMua() {
        return slMua;
    }

    public String getTenKh() {
        return tenKh;
    }

    public void setLaVip(Boolean laVip) {
        this.laVip = laVip;
    }

    public void setSlMua(Integer slMua) {
        this.slMua = slMua;
    }

    public void setTenKh(String tenKh) {
        this.tenKh = tenKh;
    }
    public double tinhThanhTien()
    {
        return (laVip?slMua*GiaBan*0.9:slMua*GiaBan);
    }
}

Code Class DanhSachKhachHang

package com.example.macbookpro.dtsondctinhtienbansach;

import java.util.ArrayList;
public class DanhSachKhachHang {
     ArrayList<KhachHang>dsKhachHang = new ArrayList<KhachHang>();
    // tao ham them khach hang vao dsKhachHang    public void themKh(KhachHang kh)
    {
        dsKhachHang.add(kh);
    }
    //Tao ham tinh tong doanh thu    public Double tongDoanhThu()
    {
        double tdt=0.0;
        for (KhachHang kh:dsKhachHang)
        {
            tdt += kh.tinhThanhTien();
        }
        return tdt;
    }
    // Tao ham tinh tong khach hang    public Integer tongKhachHang()
    {
        return dsKhachHang.size();
    }
    // Tao ham tinh tong khach VIP    public Integer tongKhachVip()
    {
        int tong =0;
        for (KhachHang kh:dsKhachHang)
        {
            if(kh.laVip)tong++;
        }
        return tong;
    }
}


Code hàm MainActivity

package com.example.macbookpro.dtsondctinhtienbansach;

import android.content.DialogInterface;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ImageButton;

public class MainActivity extends AppCompatActivity {
    Button btnThanhTien, btnTiep, btnThongKe;
    EditText edtTenKh,edtSoLuongSach, edtTongKh,edtThanhTien, edtTongVip,edtTongDoanhThu;
    CheckBox chkVip;
    ImageButton imgThoat;
    DanhSachKhachHang dsKh = new DanhSachKhachHang();

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        addControls();
        addEvents();
    }


    // Ham nay de anh xa cac control ngoai man hinh vao bien trong bo nho chinh    private void addControls() {
        btnThanhTien = (Button) findViewById(R.id.btntinhtt);
        btnTiep = (Button) findViewById(R.id.btntiep);
        btnThongKe= (Button) findViewById(R.id.btnthongke);
        edtTenKh = (EditText) findViewById(R.id.editTextTenKhachHang);
        edtSoLuongSach = (EditText) findViewById(R.id.editTextSoLuongSach);
        edtThanhTien = (EditText) findViewById(R.id.editTextThanhTien);
        edtTongKh = (EditText) findViewById(R.id.editTextTongKhachHang);
        edtTongVip = (EditText) findViewById(R.id.editTextTongKhachVip);
        edtTongDoanhThu = (EditText) findViewById(R.id.editTextTongDoanhThu);
        chkVip = (CheckBox) findViewById(R.id.checkBoxVip);
        imgThoat = (ImageButton) findViewById(R.id.imageButtonThoat);
    }
    // Goi cac xu ly da thiet lap ben duoi    private void addEvents() {
        btnThongKe.setOnClickListener(new myEvent());
        btnTiep.setOnClickListener(new myEvent());
        btnThanhTien.setOnClickListener(new myEvent());
        imgThoat.setOnClickListener(new myEvent());

    }
    // Bat cac id cua control ngoai man hinh, tuy vao id ma co cac xu ly khac nhau    // Ke thua interface View.OnClickListener va override method onClick    private class myEvent implements View.OnClickListener
    {

        @Override        public void onClick(View v) {
            switch (v.getId()){
                case R.id.btntinhtt:
                    tinhTien();
                    break;
                case R.id.btntiep:
                    tiep();
                    break;
                case R.id.btnthongke:
                    thongKe();
                    break;
                case R.id.imageButtonThoat:
                    thoat();
                    break;
            }

        }
    }
    // Viet ham Button tinh tien    private void tinhTien(){
        KhachHang kh = new KhachHang();
        kh.setTenKh(edtTenKh.getText()+"");
        kh.setSlMua(Integer.parseInt(edtSoLuongSach.getText()+""));
        kh.setLaVip(chkVip.isChecked());
        // cap nhap khach hang moi vao dsKhachHang phuc vu cho cong viec thong ke        dsKh.themKh(kh);
        edtThanhTien.setText(kh.tinhThanhTien()+"");

    }
    // Viet ham Button tiep    private void tiep()
    {
        // reset cac editText cua muc ban hang ve rong        edtTenKh.setText("");
        edtThanhTien.setText("");
        edtSoLuongSach.setText("");
        // focus vao editText ho ten        edtTenKh.requestFocus();
    }
    // viet ham cho Button Thong ke    private void thongKe()
    {
        // goi ham trong class DanhSachKhachHang de set gia tri cho cac editText trong muc thong ke        edtTongKh.setText(dsKh.tongKhachHang()+"");
        edtTongVip.setText(dsKh.tongKhachVip()+"");
        edtTongDoanhThu.setText(dsKh.tongDoanhThu()+"");
    }
    //Viet ham khi click vao imageButton Thoat    private void thoat()
    {
        AlertDialog.Builder bd = new AlertDialog.Builder(this);
        // set Title cho Alert        bd.setTitle("Thoat chuong trinh");
        // set message cho Alert        bd.setMessage("Ban co muon thoat khong?");
        // Tao button va set su kien cho button tren alert        bd.setNegativeButton("Khong", new DialogInterface.OnClickListener() {
            @Override            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        });
        bd.setPositiveButton("Co", new DialogInterface.OnClickListener() {
            @Override            public void onClick(DialogInterface dialog, int which) {
                finish();
            }
        });
        bd.create().show();

    }

}






Code xml giao diện

<?xml version="1.0" encoding="utf-8"?><ScrollView xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.macbookpro.dtsondctinhtienbansach.MainActivity"    android:fillViewport="false">


    <LinearLayout        android:orientation="vertical"        android:layout_width="match_parent"        android:layout_height="match_parent">

        <TextView            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:textAppearance="?android:attr/textAppearanceLarge"            android:text="Chuong trinh tinh tien ban hang"            android:id="@+id/textView"            android:textColor="#FFFFFF"            android:background="#FF0000"            android:layout_gravity="center_horizontal" />

        <TextView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:textAppearance="?android:attr/textAppearanceLarge"            android:text="Ban hang:"            android:textColor="#FFFFFF"            android:background="#0008ff"            android:id="@+id/textView2" />

        <TableLayout            android:layout_width="match_parent"            android:orientation="horizontal"            android:layout_height="match_parent">

            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">

                <TextView                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:textAppearance="?android:attr/textAppearanceMedium"                    android:text="Ten khac hang"                    android:id="@+id/textView3" />

                <EditText                    android:layout_width="230dp"                    android:layout_height="wrap_content"                    android:id="@+id/editTextTenKhachHang"                    android:layout_column="13" />
            </TableRow>
            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">

                <TextView                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:textAppearance="?android:attr/textAppearanceMedium"                    android:text="So luong sach"                    android:id="@+id/textView4" />

                <EditText                    android:layout_width="230dp"                    android:layout_height="wrap_content"                    android:id="@+id/editTextSoLuongSach"                    android:layout_column="13" />
            </TableRow>
            <CheckBox                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:text="Khach vip"                android:id="@+id/checkBoxVip"                android:checked="false" />
            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">

                <TextView                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:textAppearance="?android:attr/textAppearanceMedium"                    android:text="Thanh tien"                    android:id="@+id/txtThanhTien" />

                <EditText                    android:layout_width="230dp"                    android:layout_height="wrap_content"                    android:id="@+id/editTextThanhTien"                    android:layout_column="13" />
            </TableRow>

        </TableLayout>
        <LinearLayout            android:layout_width="wrap_content"            android:layout_height="wrap_content" >

            <Button                android:id="@+id/btntinhtt"                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:layout_weight="1"                android:text="Tính TT" />

            <Button                android:id="@+id/btntiep"                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:layout_weight="1"                android:text="Tiếp" />

            <Button                android:id="@+id/btnthongke"                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:layout_weight="1"                android:text="Thống kê" />
        </LinearLayout>

        <TextView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:textAppearance="?android:attr/textAppearanceLarge"            android:text="Thong ke:"            android:textColor="#FFFFFF"            android:background="#000dff"            android:id="@+id/textView10" />

        <TableLayout            android:layout_width="match_parent"            android:orientation="horizontal"            android:layout_height="match_parent">
            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">
            <TextView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:textAppearance="?android:attr/textAppearanceMedium"            android:text="Tong khach hang"            android:id="@+id/textView6" />

            <EditText                android:layout_width="150dp"                android:layout_height="wrap_content"                android:id="@+id/editTextTongKhachHang"                android:layout_column="13" />
</TableRow>
            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">
            <TextView                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:textAppearance="?android:attr/textAppearanceMedium"                android:text="Tong khach VIP"                android:id="@+id/textView7" />
            <EditText                android:layout_width="230dp"                android:layout_height="wrap_content"                android:id="@+id/editTextTongKhachVip"                android:layout_column="13" />
                </TableRow>
            <TableRow                android:layout_width="match_parent"                android:layout_height="match_parent">
            <TextView                android:layout_width="wrap_content"                android:layout_height="wrap_content"                android:textAppearance="?android:attr/textAppearanceMedium"                android:text="Tong doanh thu"                android:id="@+id/textView8" />

            <EditText                android:layout_width="230dp"                android:layout_height="wrap_content"                android:id="@+id/editTextTongDoanhThu"                android:layout_column="13" />
                </TableRow>
        </TableLayout>

        <ImageButton            android:layout_width="69dp"            android:layout_height="67dp"            android:layout_gravity="right"            android:id="@+id/imageButtonThoat"            android:src="@drawable/exit" />


    </LinearLayout>
</ScrollView>