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Find view with given x/y coords in android


is it possible to find the View that is displayed at a given absolute x/y pixel coord?



Edit: I found a suitable Solution that works great:




private View findViewByCoord(float x, float y){
TextView textView = null;
int[] location = new int[2];
int width = 0;
int height = 0;
for(int reference : cardReference){
textView = (TextView) findViewById(reference);
textView.getLocationOnScreen(location);
width = textView.getWidth();
height = textView.getHeight();
if(location[0] <= x && x <= (location[0] + width) && location[1] <= y && y <= (location[1] + height)){
Log.i("Test", "Card " + textView.getText() + " is pointed");
return textView;
}
}
return null;
}



Where cardReference is an array of integer to Resources (in my case 20 TextViews arranged in a 4 x 5 Matrix):




int[] cardReference = new int[]{R.id.card1_1, R.id.card1_2, R.id.card1_3, R.id.card1_4,
R.id.card2_1, R.id.card2_2, R.id.card2_3, R.id.card2_4,
R.id.card3_1, R.id.card3_2, R.id.card3_3, R.id.card3_4,
R.id.card4_1, R.id.card4_2, R.id.card4_3, R.id.card4_4,
R.id.card5_1, R.id.card5_2, R.id.card5_3, R.id.card5_4};



To speed up performance i would consider to use an array of TextViews then call findViewById() in every Loop.


Source: Tips4allCCNA FINAL EXAM

Comments

  1. One 'solution' would be to loop through the parent view's children and check the getLeft() and getTop() coordinates against the X and Y coordinates of your choice. If there is a match, you have your view.

    I'd like to hear other alternatives though.

    Edit: You'd also have to work out the height/width of the view too in relation to the left and top coordinates given to see if your coordinates are within that range.

    ReplyDelete

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