從零開始學習物聯網，用筆記 紀錄分享

製作一個簡易的點餐系統

將上面的選擇顯示在下面的textview裡面

view的部分如上圖所示

開啟source裡的string

<resources>
    <string name="app_name">order</string>
    <string name="desknum">桌號</string>
    <string name="custom">一般顧客</string>
    <string name="VIP">VIP</string>
    <string name="main">主餐</string>
    <string name="A">A餐100元</string>
    <string name="B">B餐150元</string>
    <string name="C">C餐200元</string>
    <string name="D">D餐250元</string>
    <string name="snack">附餐</string>
    <string name="coffee">咖啡</string>
    <string name="blacktea">紅茶</string>
    <string name="finish">結帳</string>
</resources>

程式碼的部分

1.定義

EditText etTabNum;
RadioButton rbCustom,rbVIP,rbcoffee,rbblacktea;
CheckBox cbA,cbB,cbC,cbD;
Button btn;
TextView tvShow;

2.連接

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

void findviews(){
    etTabNum=(EditText)findViewById(R.id.editText);
    rbCustom=(RadioButton)findViewById(R.id.radioButton);
    rbVIP=(RadioButton)findViewById(R.id.radioButton2);
    rbcoffee=(RadioButton)findViewById(R.id.radioButton4);
    rbblacktea=(RadioButton)findViewById(R.id.radioButton3);
    cbA=(CheckBox)findViewById(R.id.checkBox);
    cbB=(CheckBox)findViewById(R.id.checkBox3);
    cbC=(CheckBox)findViewById(R.id.checkBox2);
    cbD=(CheckBox)findViewById(R.id.checkBox4);
    btn=(Button)findViewById(R.id.button);
    btn.setOnClickListener(btnOnlick);
    tvShow=(TextView)findViewById(R.id.textView5);
}

3.按鈕

==>這部分比較複雜 分成三個步驟(觀念為：匿名內部類別實作介面)

       a.建立按鈕元件

btn=(Button)findViewById(R.id.button);

       b.建立監聽器

View.OnClickListener btnOnlick = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
    }
};

       c.註冊監聽器

btn.setOnClickListener(btnOnlick);

4.按鈕內的程式碼 ==>使用StringBuilder這個物件

StringBuilder sb = new StringBuilder();
sb.append(getResources().getString(R.string.desknum)).append(etTabNum.getText().toString()).append("\n");
if (rbCustom.isChecked()) {
    sb.append(rbCustom.getText()).append("\n");
} else {
    sb.append(rbVIP.getText()).append("\n");
}
sb.append("主餐").append("\n").append("   ");
if (cbA.isChecked()) {
    sb.append(cbA.getText()).append("\n").append(("  "));
}
if (cbB.isChecked()) {
    sb.append(cbB.getText()).append("\n").append(("  "));
}
if (cbC.isChecked()) {
    sb.append(cbC.getText()).append("\n").append(("  "));
}
if (cbD.isChecked()) {
    sb.append(cbD.getText()).append(("\n"));
}
sb.append("附餐").append("\n");
if (rbcoffee.isChecked()) {
    sb.append("  ").append(rbcoffee.getText()).append("\n");
}
if (rbblacktea.isChecked()) {
    sb.append("  ").append(rbblacktea.getText()).append("\n");
}
tvShow.setText(sb);