Android R.java文件

Question

Static id in R.java files are generated automatically but can i give then custom values to make my work easier. I have 8 Imagebuttons i need to set images on them by using this code for every button.

ImageButton button4 = (ImageButton)findViewById(R.id.iButton4);
setImagesOnButtons(myContactList.get(3).getPhotoId(),button4);

instead of doing this can i change ids of button in R.java to 1,2,3... and put the above code in a for loop like this

 for(i=0;i<8;i++)
 {
ImageButton button4 = (ImageButton)findViewById(i);
setImagesOnButtons(myContactList.get(3).getPhotoId(),i);
} 

Answer 1

You can't rely on the numbering, no. You don't want to have to be manually changing R.java . Instead, do something like this:

int[] buttonIDs = {R.id.iButton1, R.id.iButton2, ...};
for (int i = 0; i < buttonIDs.length; i++) {
  int buttonID = buttonIDs[i];
  ImageButton button4 = (ImageButton) findViewById(buttonID);
  setImagesOnButtons(myContactList.get(3).getPhotoId(), i);
}

Answer 2

EDIT: Sean Owen's answer is nicer and more compact than this one.

You could keep a map from your internal values to the unique IDs in R.java. You only need to do this once, on startup:

static final Map<Integer,Integer> buttonMap = new HashMap<Integer,Integer>();

...
buttonMap.put(4, R.id.iButton4);
buttonMap.put(3, R.id.iButton3);
...

Then you can have your loop like this:

for(i=0;i<8;i++)
{
    ImageButton button = (ImageButton)findViewById(buttonMap.get(i));
    setImagesOnButtons(myContactList.get(3).getPhotoId(),i);
}