好的，所以我刚开始尝试学习如何在Android平台上使用Eclipse进行一些编码。我编写了很多其他语言，但从来没有在这种环境中。我不知道为什么会这样......
症状：App无法在模拟器中启动。
Debugger Error: "Thread [<8> Thread-8] (Suspended (exception NullPointerException))" TutorialThread.run() line: 225
此行是结束括号。
Variables:
this (TutorialThread (id=30067699104))
c (Surface$CompaitbleCanvas (id-830067697136))
就像我说的那样，我对此非常陌生，而且我一直在关注大量的教程和大量的Google搜索。 ：/但是，我现在正在敲打键盘。非常感谢任何帮助。
package com.Joey_Ant.Lite;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;
public class JoeyAnt extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(new Panel(this));
}
}
class Panel extends SurfaceView implements SurfaceHolder.Callback {
private TutorialThread _thread;
private int _x=20;
private int _y=20;
private int _x2=20;
private int _y2=20;
private int _mx=0;
private int _my=0;
private double _angle = 0;
private int _width=50;
private int _height=50;
private double _xchange=0;
private double _ychange=0;
private double _speed=5;
private int _stage=0;
private int _level=0;
private int _swidth=0;
private int _sheight=0;
private int _bx=0;
private int _b0w=0;
private int _b0h=0;
private int _b0y=0;
private int _b1w=0;
private int _b1h=0;
private int _b1y=0;
private int _b2w=0;
private int _b2h=0;
private int _b2y=0;
private int _b3w=0;
private int _b3h=0;
private int _b3y=0;
/**
* Stage 0 - Main Menu
* Stage 1 - Controls
* Stage 2 - Introduction
* Stage 3 - Game Over
* Stage 4 - Round Win
* Stage 5 - In Game
*
*/
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
_thread.setRunning(true);
_thread.start();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
boolean retry = true;
_thread.setRunning(false);
while (retry) {
try {
_thread.join();
retry=false;
} catch (InterruptedException e) {
//Retry
}
}
}
public Panel(Context context) {
super(context);
getHolder().addCallback(this);
_thread = new TutorialThread(getHolder(), this);
setFocusable(true);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
_mx = (int) event.getX();
_my = (int) event.getY();
_x2 = _mx - (_width / 2);
_y2 = _my - (_height / 2);
if (_stage==0) {
if ((_mx > _bx)&&(_mx < _bx+_b0w)) {
// Within horizontal hit area.
if ((_my > _b0y)&&(_my < _b0y+_b0h)) {
// NEW GAME.
_stage=1;
}
}
}
return true;
}
@Override
public void onDraw(Canvas canvas) {
Paint paint = new Paint();
if (_level==0) {
}
if (_stage==0) {
paint.setStyle(Paint.Style.STROKE);
paint.setColor(Color.WHITE);
paint.setTextSize(24);
Bitmap _logo = BitmapFactory.decodeResource(getResources(), R.drawable.joeyant);
Bitmap _newgame = BitmapFactory.decodeResource(getResources(), R.drawable.new_game);
Bitmap _resumegame = BitmapFactory.decodeResource(getResources(), R.drawable.resume_game);
Bitmap _controls = BitmapFactory.decodeResource(getResources(), R.drawable.controls);
Bitmap _credits = BitmapFactory.decodeResource(getResources(), R.drawable.credits);
_swidth=canvas.getWidth();
_sheight=canvas.getHeight();
canvas.drawColor(Color.argb(255, 225, 199, 77));
canvas.drawBitmap(_logo, (_swidth/2)-(_logo.getWidth()/2), 20, null);
_bx=(_swidth/2)-(_newgame.getWidth()/2);
_b0y=150;
_b1y=210;
_b2y=270;
_b3y=330;
_b0w=_newgame.getWidth();
_b1w=_resumegame.getWidth();
_b2w=_controls.getWidth();
_b3w=_credits.getWidth();
_b0h=_newgame.getHeight();
_b1h=_resumegame.getHeight();
_b2h=_controls.getHeight();
_b3h=_credits.getHeight();
canvas.drawBitmap(_newgame, _bx, _b0y, null);
canvas.drawBitmap(_resumegame, _bx, _b1y, null);
canvas.drawBitmap(_controls, _bx, _b2y, null);
canvas.drawBitmap(_credits, _bx, _b3y, null);
}
if (_stage==1) {
// Introduction!
paint.setColor(Color.BLACK);
paint.setTextSize(18);
paint.setStyle(Paint.Style.STROKE);
Bitmap _intro = BitmapFactory.decodeResource(getResources(), R.drawable.introduction);
canvas.drawColor(Color.argb(255, 225, 199, 77));
canvas.drawBitmap(_intro, (_swidth/2)-(_intro.getWidth()/2), (_sheight/2)-(_intro.getHeight()), null);
}
if (_stage==2) {
paint.setColor(Color.WHITE);
Bitmap _scratch = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
canvas.drawColor(Color.argb(255, 225, 199, 77));
canvas.drawBitmap(_scratch, _x, _y, null);
canvas.drawText(String.valueOf(_x)+","+String.valueOf(_y)+" : "+String.valueOf(_x2)+","+String.valueOf(_y2), 20, 20, paint);
_width=_scratch.getWidth();
_height=_scratch.getHeight();
_angle = Math.atan2(_y2-_y, _x2-_x);
_xchange=Math.cos(_angle) * _speed;
_ychange=Math.sin(_angle) * _speed;
if (_x != _x2) {
_x+=_xchange;
}
if (Math.abs(_x2-_x)<_xchange) {
_x=_x2;
}
if (_y != _y2) {
_y+=_ychange;
}
if (Math.abs(_y2-_y)<_ychange) {
_y=_y2;
}
}
}
}
class TutorialThread extends Thread {
private SurfaceHolder _surfaceHolder;
private Panel _panel;
private boolean _run = false;
public TutorialThread(SurfaceHolder surfaceHolder, Panel panel) {
_surfaceHolder = surfaceHolder;
_panel = panel;
}
public void setRunning(boolean run) {
_run = run;
}
@Override
public void run() {
Canvas c;
while (_run) {
c = null;
try {
c = _surfaceHolder.lockCanvas(null);
synchronized (_surfaceHolder) {
_panel.onDraw(c);
}
} finally {
// do this in a finally so that if an exception is thrown
// during the above, we don't leave the Surface in an
// inconsistent state
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
答案 0 :(得分：0)
只是关闭这一个。我重新安装了Eclipse和Android，这种情况不复存在了。