遊戲說明：
這是一個 Android App 數字小遊戲，開始從正整數 1~100間，會隨機產生未知亂數，玩家要從範圍裡面猜出該數數值，猜對數字時，會跳出一個提示視窗，說明該亂數數值及所猜的次數，並有兩個 Button 可以選擇「Restart」或「Close」遊戲。
在過程中發現的幾個重點要注意：
1. 產生亂數的方法。
2. 控制IO (包含顯示出來的訊息及玩家所輸入的資料)，還要避免輸入空字串或錯的內容而出現 bug。
3. 資料型態轉換(text -> string > int)。
4. 跳出視窗的方法。
##ReadMore##
Step 1. 先編輯 activity_main.xml ，擺好進入 App 時的介面。
activity_main.xml Code:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/keyin"
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.gamble.MainActivity" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="110dp"
android:text="===== Gamble Start =====\nGuess the number ( 1~100 )" />
<EditText
android:id="@+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="34dp"
android:ems="10"
android:inputType="number" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/editText1"
android:layout_centerHorizontal="true"
android:layout_marginTop="79dp"
android:onClick="buttonClick1"
android:text="確定" />
</RelativeLayout>
Step 2. 編輯 strings.xml ，設定 Step1 之介面顯示出來的文字。
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">gamble</string>
<string name="hello_world"></string>
<string name="action_settings">Settings</string>
</resources>
tep3. 編輯 MainActivity.java 主程式，開始撰寫遊戲運作內容。
package com.example.gamble;
import android.support.v7.app.ActionBarActivity;
import android.text.Editable;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.util.Random;
public class MainActivity extends ActionBarActivity {
// Parameter
boolean gameWin = true;
int max, min, Ran, gameCount, guessNum;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
// Create a random number in range min ~ max
public int randomCreate(int max, int min){
Random Ran = new Random();
return (Ran.nextInt(max)+min);
}
// Button_Click event
public void buttonClick1(View view) throws InterruptedException{
// Initialize setting
if (gameWin == true) {
max = 100; // Random range (Max)
min = 1; // Random range (Min)
Ran = randomCreate(max, min); // Get random number
gameCount = 0; // Guess count
gameWin = false; // Game win flag
}
// IO setting
TextView txtOutput = (TextView) findViewById(R.id.textView1);
EditText txtInput = (EditText) findViewById(R.id.editText1);
Button txtButton = (Button) findViewById(R.id.button1);
// Alert dialog setting
AlertDialog.Builder endGame = new AlertDialog.Builder(this);
endGame.setTitle("You've guessed right!\n");
endGame.setMessage("Random Num. is \""+ Ran + "\"\nGuess count: " + gameCount);
endGame.setPositiveButton("Restart", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int i) {
// Reload App
finish();
startActivity(getIntent());
}
});
endGame.setNegativeButton("Close", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int i) {
// Close App
finish();
}
});
if ("".equals(txtInput.getText().toString().trim())) // if not any keyin
txtOutput.setText("Error Keyin, \nPlease keyin number " + min + " ~ " + max);
else {
String keyinStr = txtInput.getText().toString(); // keyinStr = Get editText1's text to string
int keyinInt = Integer.parseInt(keyinStr); // keyinInt = keyinStr to integer
if((keyinInt >= min) && (keyinInt <= max)){
gameCount += 1; // count guess number
// Determine whether the input is equal random or not.
if (keyinInt == Ran){
txtOutput.setText("");
gameWin = true;
endGame.show(); // Show "Restart" & "Close" button
}
else if (keyinInt < Ran) {
min = keyinInt;
txtOutput.setText("Guess wrong!\nThe number is " + min + " ~ " + max + " , guess again.");
}
else if (keyinInt > Ran) {
max = keyinInt;
txtOutput.setText("Guess wrong!\nThe number is " + min + " ~ " + max + " , guess again.");
}
else {
txtOutput.setText("Error"); // Other error
}
}
else
txtOutput.setText("Keyin Error, \nPlease keyin number " + min + " ~ " + max);
}
txtInput.setText(null); // clear EditText "txtInput"
}
}
遊戲執行結果：
