I am getting an exception here when I try to bring another view to the front. It happens in the last method of my BoardView class where it says if(lives == 0). Can anybody see where I should be calling this bringToFront method from??
public class BoardView extends SurfaceView implements SurfaceHolder.Callback{
Context mContext;
// thread initialization
private BoardThread thread;
Thread timer;
// box variables
Bitmap box =
(BitmapFactory.decodeResource
(getResources(), R.drawable.box));
private int box_x = 140;
private int box_y = 378;
private int boxWidth = box.getWidth();
private int boxHeight = box.getHeight();
// storage
private Vector<Blossom> blossomVector = new Vector<Blossom>();
Iterator<Blossom> dataIterator = blossomVector.iterator();
// counters
private int blossomNum = 0;
private String score;
private int currentScore = 0;
private int lives = 3;
boolean mode = false;
boolean game = false;
OutputStreamWriter out = null;
FileOutputStream fOut = null;
private static final String TAG = "Debug";
final Paint scorePaint = new Paint();
public BoardView(Context context){
super(context);
scorePaint.setColor(Color.BLACK);
scorePaint.setTextSize(12);
scorePaint.setTypeface(Typeface.MONOSPACE);
//surfaceHolder provides canvas that we draw on
getHolder().addCallback(this);
// controls drawings
thread = new BoardThread(getHolder(),this, blossomVector, dataIterator, box_x, box_y,
boxWidth, boxHeight);
timer = new Thread(){
public void run(){
//makes sure the player still has 3 lives left
while(game == false){
uiCallback.sendEmptyMessage(0);
try {
Thread.sleep(2000); // wait two seconds before drawing the next flower
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} //sleep for 2 seconds
}
}
};
timer.start();
//intercepts touch events
setFocusable(true);
}
@Override
public void onDraw(Canvas canvas){
canvas.drawColor(Color.WHITE);
score = "SCORE: " + currentScore;
//note: pay attention to order you draw things
//don't change order or else blossoms will fall
//on top of box, not "into" it.
//display the scoreboard
canvas.drawText(score,240,420,scorePaint);
// uses a synchronized method to prevent concurrent modification
DrawBlossoms(canvas);
canvas.drawBitmap(box, box_x, box_y, null);
}
@Override
public boolean onTouchEvent(MotionEvent event){
//handles movement of box
if(event.getAction() == MotionEvent.ACTION_DOWN){
if(event.getX() > box_x & event.getY() > box_y &
event.getX() < box_x + boxWidth & event.getY() < box_y + boxHeight)
{
mode = true;
}
}
if(event.getAction() == MotionEvent.ACTION_MOVE) {
if(event.getX() > box_x & event.getY() > box_y &
event.getX() < box_x + boxWidth & event.getY() < box_y + boxHeight)
{
mode = true;
}
if(mode == true){
box_x = (int)event.getX();
}
}
if(event.getAction() == MotionEvent.ACTION_UP){
mode = false;
}
invalidate();
return true;
}
@Override
public void surfaceChanged(SurfaceHolder holder,
int format, int width, int height ){
Log.v(TAG, "Surface Changed");
//somehow these don't seem to be working
}
@Override
public void surfaceCreated(SurfaceHolder holder){
thread.startRunning(true);
thread.start();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder){
Log.v(TAG, "Surface Destroyed");
//somehow these don't seem to be working
thread.startRunning(false);
thread.stop();
timer.interrupt();
timer.stop();
}
private Handler uiCallback = new Handler(){
public synchronized void handleMessage(Message msg){
//add a new blossom to the blossom Vector!!
blossomVector.add(new Blossom(
(BitmapFactory.decodeResource
(getResources(), R.drawable.blossom))));
dataIterator = blossomVector.iterator();
blossomNum++;
Log.v(TAG, "Number of Blossoms =" + blossomNum);
}
};
private synchronized void DrawBlossoms(Canvas c) // method to draw flowers on screen and test for collision
{
Canvas canvas = c;
dataIterator = blossomVector.iterator();
while (dataIterator.hasNext())
{
Blossom tempBlossom = dataIterator.next();
tempBlossom.Draw(canvas);
if (tempBlossom.hit(box_x,box_y, box_x + boxWidth, box_y + boxHeight, blossomVector) == true)
{
Log.v(TAG, "ITERATOR WORKS!");
dataIterator.remove();
currentScore += 100;
}
if (tempBlossom.dropped() == true)
{
dataIterator.remove();
Log.v(TAG, "Blossom dropped");
lives--;
}
if (lives == 0)
{
// END THE GAME!!!
((BoardView) getParent()).findViewById(1).bringToFront();
}
}
}
public void writeFile()
{
}
}
public class BoardThread extends Thread {
private SurfaceHolder surfaceHolder;
private BoardView boardView;
private Vector<Blossom> blossomVector;
private int boxX;
private int boxY;
private int boxWidth;
private int boxHeight;
private boolean mrun =false;
private Iterator<Blossom> iterator;
private static final String TAG = "Debug";
public BoardThread(SurfaceHolder holder, BoardView boardView2,
Vector<Blossom> blossomVector1, Iterator<Blossom> dataIterator,
int box_x, int box_y, int boxW, int boxH) {
surfaceHolder = holder;
boardView=boardView2;
blossomVector = blossomVector1;
iterator = dataIterator;
boxX = box_x;
boxY = box_y;
boxW = boxWidth;
boxH = boxHeight;
}
public void startRunning(boolean run) {
mrun=run;
}
@Override
public void run() {
super.run();
Canvas canvas;
while (mrun) {
canvas=null;
try {
canvas = surfaceHolder.lockCanvas(null);
synchronized (surfaceHolder) {
//update position
//Position(blossomVector, boxX, boxY, boxWidth, boxHeight);
// draw flowers
boardView.onDraw(canvas);
}
} finally {
if (canvas != null) {
surfaceHolder.unlockCanvasAndPost(canvas);
}
}
}
}
private synchronized void Position(Vector<Blossom> blossomVector,int box_x, int box_y,
int boxWidth, int boxHeight)
{
//for(Blossom blossom: blossomVector)
iterator = blossomVector.iterator();
while (iterator.hasNext())
{
Blossom tempBlossom = iterator.next();
tempBlossom.UpdatePosition();
}
}
}
public class Board extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
//use a frame layout so you can also display a dialog box
// allows more than one view to be used
FrameLayout f1 = new FrameLayout(this);
LinearLayout l1 = new LinearLayout(this);
EditText edit = new EditText(this);
l1.setOrientation(LinearLayout.VERTICAL);
l1.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT));
edit.setText("Enter your name!");
l1.setId(1);
l1.addView(edit);
f1.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
f1.addView(l1);
f1.addView(new BoardView(this));
setContentView(f1);
//setContentView(new BoardView(this));
}
}
You need to run the bring to front on the right thread. Try this:
final View v = ((BoardView) getParent()).findViewById(1);
v.post(new Runnable(){ public void run(){ v.bringToFront(); } });
See if that works.
You must update the View using the UI thread (not the SurfaceView thread). If you would like to make some View change from within the SurfaceView thread you must create a new RunOnUiThread which performs the View updating.
// From within SurfaceView thread
new Thread() {
public void run() {
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
// Update view here
}
});
}
}.start();
来源：https://stackoverflow.com/questions/5928755/called-from-wrong-thread-exception