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當我運行下面的一切工作正常的代碼，它與三個球一個簡單的應用程序，你可以走動...的onTouchEvent（）問題的android
public class dragndrop extends Activity {
/** Called when the activity is first created. */
private ColorBall[] colorballs = new ColorBall[3]; // array that holds the balls
private static final String TAG="MyTAG";
DrawView myView;
private int balID = 0; // variable to know what ball is being dragged
int X;
int Y;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Point point1 = new Point();
point1.x = 50;
point1.y = 20;
Point point2 = new Point();
point2.x = 100;
point2.y = 20;
Point point3 = new Point();
point3.x = 150;
point3.y = 20;
// declare each ball with the ColorBall class
colorballs[0] = new ColorBall(this,R.drawable.bol_groen, point1);
colorballs[1] = new ColorBall(this,R.drawable.bol_rood, point2);
colorballs[2] = new ColorBall(this,R.drawable.bol_blauw, point3);
myView = new DrawView(this);
setContentView(myView);
}
public class DrawView extends View {
public DrawView(Context context) {
super(context);
setFocusable(true); //necessary for getting the touch events
// setting the start point for the balls
}
// the method that draws the balls
@Override protected void onDraw(Canvas canvas) {
//draw the balls on the canvas
for (ColorBall ball : colorballs) {
canvas.drawBitmap(ball.getBitmap(), ball.getX(), ball.getY(), null);
}
}
// events when touching the screen
public boolean onTouchEvent(MotionEvent event) {
int eventaction = event.getAction();
X = (int)event.getX();
Y = (int)event.getY();
switch (eventaction) {
case MotionEvent.ACTION_DOWN: // touch down so check if the finger is on a ball
balID = 0;
for (ColorBall ball : colorballs) {
Log.d(TAG,"inside action down inside for coords:"+X+" coords: "+Y);
Log.d(TAG,"ball coords:"+ball.getX()+" coords: "+ball.getY());
int x =X;
int y =Y;
Log.d(TAG,"lalalalalala"+x+" coords: "+y);
if (x > ball.getX() && x < ball.getX()+50 && y > ball.getY() && y < ball.getY()+50){//if (X > ball.getX() && X < ball.getX()+50 && Y > ball.getY() && Y < ball.getY()+50){
Log.d(TAG,"inside ball coords!!!!!!!!!!!!!!!!!!!!!!!!:"+ball.getX()+" coords: "+ball.getY());
balID = ball.getID();
break;
}
}
break;
case MotionEvent.ACTION_MOVE: // touch drag with the ball
// move the balls the same as the finger
if (balID > 0) {
colorballs[balID-1].setX(X-25);
colorballs[balID-1].setY(Y-25);
}
break;
case MotionEvent.ACTION_UP:
// touch drop - just do things here after dropping
break;
}
// redraw the canvas
myView.invalidate();
return true;
}
}
}
但是當我嘗試從處理的onTouchEvent主要活動不起作用，奇怪的是它不能讀取一個簡單的變量（x，y）！ 我不明白爲什麼會發生這種情況，它似乎只有在視圖中才能使它們變紅！
public class dragndrop extends Activity {
/** Called when the activity is first created. */
private ColorBall[] colorballs = new ColorBall[3]; // array that holds the balls
private static final String TAG="MyTAG";
DrawView myView;
private int balID = 0; // variable to know what ball is being dragged
int X;
int Y;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Point point1 = new Point();
point1.x = 50;
point1.y = 20;
Point point2 = new Point();
point2.x = 100;
point2.y = 20;
Point point3 = new Point();
point3.x = 150;
point3.y = 20;
// declare each ball with the ColorBall class
colorballs[0] = new ColorBall(this,R.drawable.bol_groen, point1);
colorballs[1] = new ColorBall(this,R.drawable.bol_rood, point2);
colorballs[2] = new ColorBall(this,R.drawable.bol_blauw, point3);
myView = new DrawView(this);
setContentView(myView);
}
// events when touching the screen
public boolean onTouchEvent(MotionEvent event) {
int eventaction = event.getAction();
X = (int)event.getX();
Y = (int)event.getY();
switch (eventaction) {
case MotionEvent.ACTION_DOWN: // touch down so check if the finger is on a ball
balID = 0;
for (ColorBall ball : colorballs) {
Log.d(TAG,"inside action down inside for coords:"+X+" coords: "+Y);
Log.d(TAG,"ball coords:"+ball.getX()+" coords: "+ball.getY());
int x =X;
int y =Y;
Log.d(TAG,"lalalalalala"+x+" coords: "+y);
if (x > ball.getX() && x < ball.getX()+50 && y > ball.getY() && y < ball.getY()+50){//if (X > ball.getX() && X < ball.getX()+50 && Y > ball.getY() && Y < ball.getY()+50){
Log.d(TAG,"inside ball coords!!:"+ball.getX()+" coords: "+ball.getY());
balID = ball.getID();
break;
}
}
break;
case MotionEvent.ACTION_MOVE: // touch drag with the ball
// move the balls the same as the finger
if (balID > 0) {
colorballs[balID-1].setX(X-25);
colorballs[balID-1].setY(Y-25);
}
break;
case MotionEvent.ACTION_UP:
// touch drop - just do things here after dropping
break;
}
// redraw the canvas
myView.invalidate();
return true;
}
public class DrawView extends View {
public DrawView(Context context) {
super(context);
setFocusable(true); //necessary for getting the touch events
// setting the start point for the balls
}
// the method that draws the balls
@Override protected void onDraw(Canvas canvas) {
//canvas.drawColor(0xFFCCCCCC); //if you want another background color
//draw the balls on the canvas
for (ColorBall ball : colorballs) {
canvas.drawBitmap(ball.getBitmap(), ball.getX(), ball.getY(), null);
}
}
}
}
任何知道爲什麼的人？
是@bigstones onTouchevent正在工作，它捕獲所有的動作，問題是如果我在活動內部有ontouchevent代碼，變量X，Y似乎不工作儘管他們有一個值，我可以打印它（或日誌）我說的是測試，我已經嘗試並將if（）語句（getX，getY）中的所有值更改爲整數，並且它不適用於X，Y .....請再次檢查代碼！ 謝謝！
根據引用，僅當沒有任何視圖使用事件時才調用Activity.onTouchEvent（）。也許這讓你的觀點變得焦點，使得它「吃」所有的事件？ Activity.onTouchEvent（）被調用嗎？ （請在回答中添加@bigstones，以便我收到通知） – bigstones 2011-01-25 21:24:53
下一次正確格式化您的代碼，並儘量不要發佈您的整個代碼，並讓我們通過它。 – Falmarri 2011-01-25 21:42:54