在我的简单代码中，我创建了一个具有随机颜色和不透明度的圆圈，它会移动一段时间然后消失。它按预期工作。
class Circle1Thread extends Thread {
@Override
public void run() {
prev_time = System.currentTimeMillis();
while(running) {
Canvas canvas = null;
switch(state) {
case States.NONE:
try {
canvas = surfaceHolder.lockCanvas();
if (!counted) {
width = canvas.getWidth();
height = canvas.getHeight();
counted = true;
}
got_direction = false;
paint = new Paint();
paint.setColor(States.getRandomColor()); // random color
paint.setAlpha(random.nextInt(250)); //random alpha
radius = (float) random.nextInt(width/4); // random radius
x = random.nextInt((int)(width-2*radius)) + radius;
y = random.nextInt((int)(height-2*radius)) + radius; // random x & y positions
current_radius = 1;
synchronized(surfaceHolder) {
canvas.drawColor(Color.WHITE);
canvas.drawCircle(x, y, current_radius, paint); // draw almost unseen circle, than increasing its radius
}
}
finally {
if (canvas!= null) surfaceHolder.unlockCanvasAndPost(canvas);
else Log.d("canvas","canvas is null in thread 1");
state = States.APPEARING;
creation_time = System.currentTimeMillis();
}
break;
case States.APPEARING:
if ((now_time = System.currentTimeMillis() - prev_time) >=15) {
current_radius = current_radius +3;
if (current_radius >=radius) {
state = States.MOVING;
break;
}
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
canvas.drawColor(Color.WHITE);
canvas.drawCircle(x, y, current_radius, paint);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time = now_time;
}
break;
case States.MOVING:
if (!got_direction) {
direction = States.getDirection();
got_direction = true;
}
if (((now_time = System.currentTimeMillis()) - prev_time) >=15) {
switch(direction) {
case States.DIRECTION_DOWN:
y = y+2;
break;
case States.DIRECTION_LEFT:
x =x-2;
break;
case States.DIRECTION_RIGHT:
x = x+2;
break;
case States.DIRECTION_UP:
y = y-2;
break;
}
}
if((now_time - creation_time) >=4000) {
state = States.DISAPPEARING;
break;
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
canvas.drawColor(Color.WHITE);
canvas.drawCircle(x, y, radius, paint);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time = now_time;
}
break;
case States.DISAPPEARING:
if ((now_time = System.currentTimeMillis() - prev_time) >=15) {
current_radius = current_radius -3;
if (current_radius <=1) {
state = States.NONE;
break;
}
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
canvas.drawColor(Color.WHITE);
canvas.drawCircle(x, y, current_radius, paint);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time = now_time;
}
break;
}
}
}
}
但我不知道如何创建几个圆圈，这些圆圈的行为方式类似。我尝试这样做，但它无法正常工作。
class Circle1Thread extends Thread {
public Circle1Thread(SurfaceHolder holder) {
surfaceHolder = holder;
random = new Random();
canvas = surfaceHolder.lockCanvas();
canvas.drawColor(Color.WHITE);
surfaceHolder.unlockCanvasAndPost(canvas);
}
public void setRunning(boolean run) {
running = run;
}
@Override
public void run() {
while(running) {
for(int count=0; count<5; count++) {
canvas = surfaceHolder.lockCanvas();
canvas.drawColor(Color.WHITE);
surfaceHolder.unlockCanvasAndPost(canvas);
Log.d("canvas" ,"operating in count = "+String.valueOf(count));
Canvas canvas = null;
if (!was_created[count]) prev_time[count] = System.currentTimeMillis();
switch(state[count]) {
case States.NONE:
try {
canvas = surfaceHolder.lockCanvas();
if (!counted) {
width = canvas.getWidth();
height = canvas.getHeight();
counted = true;
}
got_direction[count] = false;
paint[count] = new Paint();
paint[count].setColor(States.getRandomColor()); // random color
paint[count].setAlpha(random.nextInt(250)); //random alpha
radius[count] = (float) random.nextInt(width/4); // random radius
x[count] = random.nextInt((int)(width-2*radius[count])) + radius[count];
y[count] = random.nextInt((int)(height-2*radius[count])) + radius[count]; // random x & y positions
current_radius[count] = 1;
was_created[count] = true;
synchronized(surfaceHolder) {
Log.d("canvas","color drawn in count = "+String.valueOf(count));
canvas.drawCircle(x[count], y[count], current_radius[count], paint[count]); // draw almost unseen circle, than increasing its radius
}
}
finally {
if (canvas!= null) surfaceHolder.unlockCanvasAndPost(canvas);
else Log.d("canvas","canvas is null in thread 1");
state[count] = States.APPEARING;
creation_time[count] = System.currentTimeMillis();
}
break;
case States.APPEARING:
if (((now_time[count] = System.currentTimeMillis()) - prev_time[count]) >=15) {
current_radius[count] = current_radius[count] +3;
Log.d("radius",String.valueOf(radius[count])+" in count = "+String.valueOf(count));
if (current_radius[count] >=radius[count]) {
state[count] = States.MOVING;
break;
}
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
Log.d("canvas","appearing in count = "+String.valueOf(count)+", radius = "+String.valueOf(current_radius[count]));
canvas.drawCircle(x[count], y[count], current_radius[count], paint[count]);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time[count] = now_time[count];
}
break;
case States.MOVING:
if (!got_direction[count]) {
direction[count] = States.getDirection();
got_direction[count] = true;
}
if (((now_time[count] = System.currentTimeMillis()) - prev_time[count]) >=15) {
switch(direction[count]) {
case States.DIRECTION_DOWN:
y[count] = y[count]+2;
break;
case States.DIRECTION_LEFT:
x[count] =x[count]-2;
break;
case States.DIRECTION_RIGHT:
x[count] = x[count]+2;
break;
case States.DIRECTION_UP:
y[count] = y[count]-2;
break;
}
}
if((now_time[count] - creation_time[count]) >=4000) {
state[count] = States.DISAPPEARING;
break;
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
Log.d("canvas","moving in count = "+String.valueOf(count));
canvas.drawCircle(x[count], y[count], radius[count], paint[count]);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time = now_time;
}
break;
case States.DISAPPEARING:
if ((now_time[count] = System.currentTimeMillis() - prev_time[count]) >=15) {
current_radius[count] = current_radius[count] -3;
if (current_radius[count] <=1) {
state[count] = States.NONE;
break;
}
}
try {
canvas = surfaceHolder.lockCanvas();
synchronized (surfaceHolder) {
Log.d("canvas","disappearing in count = "+String.valueOf(count));
canvas.drawCircle(x[count], y[count], current_radius[count], paint[count]);
}
}
finally {
surfaceHolder.unlockCanvasAndPost(canvas);
prev_time[count] = now_time[count];
}
break;
}
}
}
}}
有人可以帮忙吗？