Spinner與訊息方塊

Spinner與訊息方塊_Demo

1、設計好xml畫面

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Spinner
android:id="@+id/choise"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<EditText
android:id="@+id/input"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="number" >
<requestFocus />
</EditText>
<Button
android:id="@+id/check"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="轉換"
android:onClick="btnClick" />
</LinearLayout>

2、到values/string.xml新增字串陣列(增減直接對xml修改即可不必再修改程式碼)

3、撰寫Activity程式碼

package com.android.final_test_15_6_9;
import com.android.final_test_14_6_9.R;
import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.SpinnerAdapter;
public class Final_Test_15_6_9Activity extends Activity{
/** Called when the activity is first created. */
private Spinner spChoise;
private static String[] sChoise;
private EditText edInput;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);//接收xml畫面
sChoise = getResources().getStringArray(R.array.sCheck);//Spinner元件sChoise接收在string.xml內的陣列文字
spChoise = (Spinner) findViewById(R.id.choise);
edInput = (EditText) findViewById(R.id.input);
ArrayAdapter<String> a = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,sChoise);//宣告ArrayAdapter承接字串陣列
spChoise.setAdapter(a);//設定Adapter至Spinner
}
public void btnClick(View view){
AlertDialog.Builder builder = new AlertDialog.Builder(this);//對話方塊
builder.setTitle("轉換結果");
double dInput = Double.valueOf(edInput.getText().toString());
if (spChoise.getSelectedItem().equals(sChoise[0]))
builder.setMessage(String.format("華氏%.2f度，轉為攝氏%.2f度", dInput,(dInput-32.0)*5.0/9.0));
else if (spChoise.getSelectedItem().equals(sChoise[1]))
builder.setMessage(String.format("攝氏%.2f度，轉為華氏%.2f度", dInput,dInput*(9.0/5.0)+32.0));
builder.setPositiveButton("確定", null);
builder.show();
}
}

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