我有代码可以拖放和移动下面的图像
在那我通过按下按钮动态添加图像。
但是当我添加一张图片时,我失去了前一张图片的联系。这意味着我无法通过添加图像来移动上一张图像。我只能控制新创建的图像
public class DragAndDropBasicActivity extends Activity implements OnTouchListener {
private ImageView letterView; // The letter that the user drags.
private ImageView emptyLetterView; // The letter outline that the user is supposed to drag letterView to.
private AbsoluteLayout mainLayout;
private Button butClick;
int i = 0;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mainLayout = (AbsoluteLayout) findViewById(R.id.mainLayout);
mainLayout.setOnTouchListener(this);
emptyLetterView = (ImageView) findViewById(R.id.emptyLetterView);
butClick = (Button)findViewById(R.id.button1);
butClick.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
letterView = new ImageView(DragAndDropBasicActivity.this);
letterView.setId(i++);
letterView.setImageResource(R.drawable.hk_a1);
letterView.setOnTouchListener(DragAndDropBasicActivity.this);
mainLayout.addView(letterView);
}
});
}
private boolean dragging = false;
private Rect hitRect = new Rect();
@Override
/**
* NOTE: Had significant problems when I tried to react to ACTION_MOVE on letterView. Kept getting alternating (X,Y)
* locations of the motion events, which caused the letter to flicker and move back and forth. The only solution I could
* find was to determine when the user had touched down on the letter, then process moves in the ACTION_MOVE
* associated with the mainLayout.
*/
public boolean onTouch(View v, MotionEvent event) {
boolean eventConsumed = true;
int x = (int)event.getX();
int y = (int)event.getY();
int action = event.getAction();
if (action == MotionEvent.ACTION_DOWN) {
if (v == letterView) {
dragging = true;
eventConsumed = false;
}
} else if (action == MotionEvent.ACTION_UP) {
if (dragging) {
emptyLetterView.getHitRect(hitRect);
if (hitRect.contains(x, y))
setSameAbsoluteLocation(letterView, emptyLetterView);
}
dragging = false;
eventConsumed = false;
} else if (action == MotionEvent.ACTION_MOVE) {
if (v != letterView) {
if (dragging) {
setAbsoluteLocationCentered(letterView, x, y);
}
}
}
return eventConsumed;
}
private void setSameAbsoluteLocation(View v1, View v2) {
AbsoluteLayout.LayoutParams alp2 = (AbsoluteLayout.LayoutParams) v2.getLayoutParams();
setAbsoluteLocation(v1, alp2.x, alp2.y);
}
private void setAbsoluteLocationCentered(View v, int x, int y) {
setAbsoluteLocation(v, x - v.getWidth() / 2, y - v.getHeight() / 2);
}
private void setAbsoluteLocation(View v, int x, int y) {
AbsoluteLayout.LayoutParams alp = (AbsoluteLayout.LayoutParams) v.getLayoutParams();
alp.x = x;
alp.y = y;
v.setLayoutParams(alp);
}
}
谁能帮我控制以前添加的图像,以便我可以移动以前添加的图像。