I've been trying to write a little application that recognizes custom events in Android: you hold your finger over a TextView for a certain length of time, and it changes color. I'm using the MotionEvent coordinates and checking if they are within the bounds of a particular TextView, which is within a table.
private boolean checkBounds(TextView v, MotionEvent event) {
int[] origin = new int[2];
v.getLocationOnScreen(origin);
if ((event.getX() > origin[0]) && (event.getX() < (origin[0] + v.getMeasuredWidth()))) {
if ((event.getY() > origin[1]) && (event.getY() < (origin[1] + v.getMeasuredHeight()))) {
return true;
}
}
return false;
}
I am just attaching the onTouch listener to the table within the activity. But I get weird errors: the coor开发者_如何学Pythondinates seem to be off by one view (i.e. if I touch the view below the view above reacts); or sometimes one will react, and the other will not. Any idea what might be going on?
I usually happens because of the size of the notification bar.... try to do this:
private boolean checkBounds(TextView v, MotionEvent event) {
// here you will have to get a reference of the global view (the View that holds the UI)
View globalView = ...; // the main view of my activity/application
DisplayMetrics dm = new DisplayMetrics();
this.getWindowManager().getDefaultDisplay().getMetrics(dm);
int topOffset = dm.heightPixels - globalView.getMeasuredHeight();
int[] origin = new int[2];
v.getLocationOnScreen(origin);
final int x = origin[0];
final int y = origin[1] - topOffset;
if ((event.getX() > x) && (event.getX() < (x + v.getMeasuredWidth()))) {
if ((event.getY() > y) && (event.getY() < (y + v.getMeasuredHeight()))) {
return true;
}
}
return false;
}
Anyway... I'm sure there are better ways to implement what you want. As far as I know, TextView
s are able to send OnClik
events.
using getRawX() getRawY() seems to work.
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