package com.example.prova;
import java.util.Enumeration;
import java.util.Hashtable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Color;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class ScassaLaTalpa extends Activity
implements android.view.View.OnClickListener,
TextWatcher {
int life = 3;
public static int NUMBER_OF_CELLS = 16;
Hashtable<Integer, Button> buttons =
new Hashtable<Integer, Button>();
TextView lose;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_play);
buttons = populateGrid(buttons);
Enumeration<Integer> keys = buttons.keys();
while(keys.hasMoreElements()){
Integer key = (Integer) keys.nextElement();
Button btn = buttons.get(key);
btn.setText("");
btn.setOnClickListener(this);
}
lose = (TextView) findViewById(R.id.lose);
lose.addTextChangedListener(this);
lose.setText(life + "");
SpawnButton sb = new SpawnButton();
sb.execute();
}
class SpawnButton extends AsyncTask<Void, Button, String> {
@Override
protected String doInBackground(Void...voids) {
Button randomBtn= null;
while(life > 0){
int randomBtnNumber = (int) (Math.random() * 16);
randomBtn= buttons.get(randomBtnNumber );
publishProgress(randomBtn);
try {
Thread.sleep(1500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
publishProgress(randomBtn);
}
return "";
}
@Override
protected void onProgressUpdate(Button... values) {
// TODO Auto-generated method stub
if(values[0].getText().equals("")
values[0].setText("X");
else
values[0].setText("");
}
@Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
TextView lose = (TextView) findViewById(R.id.lose);
lose.setText("You lose!");
Enumeration<Integer> keys = buttons.keys();
while(keys.hasMoreElements()){
Integer key = (Integer) keys.nextElement();
Button btn = buttons.get(key);
btn.setBackgroundColor(Color.BLACK);
btn.setEnabled(false);
}
}
}
public void onClick(View v) {
// TODO Auto-generated method stub
Button btn= (Button) v;
if(btn.getText().equals("X")){ // ??
btn.setText("");
} else {
life--;
lose.setText(life + "");
}
}
/* UTILS METHOD */
public Hashtable<Integer, Button> populateGrid(
Hashtable<Integer,
Button> buttons){
buttons.put(1, (Button) findViewById(R.id.btn1));
buttons.put(2, (Button) findViewById(R.id.btn2));
buttons.put(3, (Button) findViewById(R.id.btn3));
buttons.put(4, (Button) findViewById(R.id.btn4));
buttons.put(5, (Button) findViewById(R.id.btn5));
buttons.put(6, (Button) findViewById(R.id.btn6));
buttons.put(7, (Button) findViewById(R.id.btn7));
buttons.put(8, (Button) findViewById(R.id.btn8));
buttons.put(9, (Button) findViewById(R.id.btn9));
buttons.put(10, (Button) findViewById(R.id.btn10));
buttons.put(11, (Button) findViewById(R.id.btn11));
buttons.put(12, (Button) findViewById(R.id.btn12));
buttons.put(13, (Button) findViewById(R.id.btn13));
buttons.put(14, (Button) findViewById(R.id.btn14));
buttons.put(15, (Button) findViewById(R.id.btn15));
buttons.put(16, (Button) findViewById(R.id.btn16));
return buttons;
}
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
if(s.toString().equals("0"))
lose.setTextColor(Color.RED);
else if(s.toString().equals("1"))
lose.setTextColor(Color.MAGENTA);
else if(s.toString().equals("2"))
lose.setTextColor(Color.YELLOW);
else if(s.toString().equals("3"))
lose.setTextColor(Color.GREEN);
}
public void beforeTextChanged(CharSequence s,
int start,
int count,
int after) {
// TODO Auto-generated method stub
}
public void onTextChanged(CharSequence s,
int start,
int before,
int count) {
// TODO Auto-generated method stub
}
}
我的目标是创建一个按钮网格并将按钮文本随机设置为“X”。我想模拟“鼹鼠猎人”游戏。因此，当按下激活的按钮时，文本将设置为“”以取消激活它。当按下未激活的按钮时，生命将减一。等等......这段代码有效，但它经常崩溃......我没有使用好的线程方法？
12-18 21:20:01.500: E/AndroidRuntime(1270): FATAL EXCEPTION: main
12-18 21:20:01.500: E/AndroidRuntime(1270): java.lang.NullPointerException
12-18 21:20:01.500: E/AndroidRuntime(1270): at com.example.pwnthamarmot.ScassaLaTalpa$SpawnMarmot.onProgressUpdate(ScassaLaTalpa.java:80)
12-18 21:20:01.500: E/AndroidRuntime(1270): at com.example.pwnthamarmot.ScassaLaTalpa$SpawnMarmot.onProgressUpdate(ScassaLaTalpa.java:1)
12-18 21:20:01.500: E/AndroidRuntime(1270): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:432)
12-18 21:20:01.500: E/AndroidRuntime(1270): at android.os.Handler.dispatchMessage(Handler.java:99)
12-18 21:20:01.500: E/AndroidRuntime(1270): at android.os.Looper.loop(Looper.java:130)
12-18 21:20:01.500: E/AndroidRuntime(1270): at android.app.ActivityThread.main(ActivityThread.java:3687)
12-18 21:20:01.500: E/AndroidRuntime(1270): at java.lang.reflect.Method.invokeNative(Native Method)
12-18 21:20:01.500: E/AndroidRuntime(1270): at java.lang.reflect.Method.invoke(Method.java:507)
12-18 21:20:01.500: E/AndroidRuntime(1270): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
12-18 21:20:01.500: E/AndroidRuntime(1270): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
12-18 21:20:01.500: E/AndroidRuntime(1270): at dalvik.system.NativeStart.main(Native Method)