package com.zms.dicedemo;  import java.util.Random;  import android.app.Activity; import android.graphics.drawable.Drawable; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.Toast;  public class MainActivity extends Activity {   private ImageView imageDice;  private Button btnGo;   @Override  protected void onCreate(Bundle savedInstanceState) {   super.onCreate(savedInstanceState);   setContentView(R.layout.activity_main);    initialLayout();  }   private void initialLayout() {   imageDice = (ImageView) findViewById(R.id.imageDice);    btnGo = (Button) findViewById(R.id.btnGo);   btnGo.setOnClickListener(new MyOnClickListener());   }   class MyOnClickListener implements View.OnClickListener {    @Override   public void onClick(View v) {    switch (v.getId()) {    case R.id.btnGo:     imageDice.setImageDrawable(getResources().getDrawable(       R.drawable.anim_dice));     new Thread(new DiceThread()).start();     break;     default:     break;    }    }  }   public class DiceThread implements Runnable {    @Override   public void run() {    try {     Thread.sleep(2000);    } catch (InterruptedException e) {     e.printStackTrace();    }     Message messageDice = new Message();    messageDice.what = 1;    diceHandler.sendMessage(messageDice);    }   }   private void resetDiceImage() {   int randomInt = 1 + new Random().nextInt(6); // 1~6   Toast.makeText(MainActivity.this, getChineseByNumber(randomInt),     Toast.LENGTH_SHORT).show();   imageDice.setImageDrawable(getResources().getDrawable(     getResources().getIdentifier("dice_" + randomInt, "drawable",       getPackageName())));  }   private String getChineseByNumber(int number) {   switch (number) {   case 1:    return "一點小";    case 2:    return "二點小";    case 3:    return "三點小";    case 4:    return "四點大";    case 5:    return "五點大";    case 6:    return "六點大";    default:    return "";   }  }   final Handler diceHandler = new Handler() {    public void handleMessage(android.os.Message msg) {    switch (msg.what) {    case 1:     resetDiceImage();     break;     default:     break;    }   }   }; }