Findviewbyid() in for loop

Question

I have tried this, but I didn't understand how to make custom names for my variables. Here is the code that I want to make shorter:

    TextView viewmt1 = (TextView) v.findViewById(R.id.mt1);
    TextView viewmt2 = (TextView) v.findViewById(R.id.mt2);
    TextView viewmt3 = (TextView) v.findViewById(R.id.mt3);
    TextView viewmt4 = (TextView) v.findViewById(R.id.mt4);
    TextView viewmt5 = (TextView) v.findViewById(R.id.mt5);
    TextView viewmt6 = (TextView) v.findViewById(R.id.mt6);
    TextView viewmt7 = (TextView) v.findViewById(R.id.mt7);

    TextView viewtid1 = (TextView) v.findViewById(R.id.tid1);
    TextView viewtid2 = (TextView) v.findViewById(R.id.tid2);
    TextView viewtid3 = (TextView) v.findViewById(R.id.tid3);
    TextView viewtid4 = (TextView) v.findViewById(R.id.tid4);
    TextView viewtid5 = (TextView) v.findViewById(R.id.tid5);
    TextView viewtid6 = (TextView) v.findViewById(R.id.tid6);
    TextView viewtid7 = (TextView) v.findViewById(R.id.tid7);

    ImageView viewImage1 = (ImageView) v.findViewById(R.id.imageView1);
    ImageView viewImage2 = (ImageView) v.findViewById(R.id.imageView2);
    ImageView viewImage3 = (ImageView) v.findViewById(R.id.imageView3);
    ImageView viewImage4 = (ImageView) v.findViewById(R.id.imageView4);
    ImageView viewImage5 = (ImageView) v.findViewById(R.id.imageView5);
    ImageView viewImage6 = (ImageView) v.findViewById(R.id.imageView6);
    ImageView viewImage7 = (ImageView) v.findViewById(R.id.imageView7);

you can create dynamic Taxtview and Imageview and add on your Linear or Relative layout — Saif, Oct 28 '17 at 12:28
Did you try this? https://stackoverflow.com/a/4865350/5137352 — Nabin Bhandari, Oct 28 '17 at 12:32
If all/most your views are similar you should be using a RecyclerView — Veneet Reddy, Oct 28 '17 at 12:37

KeLiuyue · Accepted Answer · 2017-10-28T12:55:44.310

2

1.init TextView、ImageView array

2.add for loop

3.get id of the view

4.findViewById in the code

Try this .

TextView[]  textViews1 = new TextView[7];
TextView[]  textViews2 = new TextView[7];
ImageView[]  imageViews = new ImageView[7];

for (int j = 0; j < 7; j++) {
    String viewmt = "mt" + (i + 1);
    String viewtid = "tid" + (i + 1);
    String viewImage = "imageView" + (i + 1);
    int resIDmt = getResources().getIdentifier(viewmt, "id", getPackageName());
    int resIDtid = getResources().getIdentifier(viewtid, "id", getPackageName());
    int resIDImage = getResources().getIdentifier(viewImage, "id", getPackageName());

    textViews1[j] = ((TextView) v.findViewById(resIDmt));
    textViews2[j] = ((TextView) v.findViewById(resIDtid));
    imageViews[j] = ((ImageView) v.findViewById(resIDImage));
}

edited Oct 28 '17 at 12:55

answered Oct 28 '17 at 12:38

KeLiuyue

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Can I access the variables outide the for-loop using their custom names? – Bestem0r Oct 28 '17 at 12:40
You can use `imageViews[0]` 、`imageViews[1]` .And you can `ImageView[] imageViews = new ImageView[7];` as global variables .And you can access all the place . – KeLiuyue Oct 28 '17 at 12:43
Can I type textViews1[1].setText(String);? – Bestem0r Oct 28 '17 at 12:52
It shows nothing. This is my String: `final SharedPreferences smt1 = getActivity().getSharedPreferences("stot1", Context.MODE_PRIVATE); String mt1 = smt1.getString("stot1", "");` – Bestem0r Oct 28 '17 at 12:55
Sorry ,I forgot to add `v.` in the code .You can try again. – KeLiuyue Oct 28 '17 at 12:56
And you can show the "hello world" to try first .Then add string to it . – KeLiuyue Oct 28 '17 at 12:57
It works with "hello world!", but not with my String – Bestem0r Oct 28 '17 at 12:59
So it did not have data in `mt1` .You can check the `SharedPreferences` in your code . – KeLiuyue Oct 28 '17 at 13:01
After fixing my SharedPreference it worked! Thank you! – Bestem0r Oct 28 '17 at 14:38
Good luck to you.@KjellØdegård – KeLiuyue Oct 28 '17 at 14:48
You are the most helpful guy I have ever met on the internet. Can you help me with this? https://stackoverflow.com/questions/47240467/android-wont-provide-animation – Bestem0r Nov 11 '17 at 18:03
I will check it for you tomorrow.@KjellØdegård – KeLiuyue Nov 12 '17 at 01:19

Titus · Answer 2 · 2017-10-28T12:45:20.593

You can't really define variable names at compile time. The easiest solution will be to store all those views into an array or something like that. Here is an example:

class Component{
    TextView mt;
    TextView tid;
    ImageView img;
    public Component(TextView mt, TextView tid, ImageView img){
        this.mt = mt;
        this.tid = tid;
        this.id = id;
    }
}

.....
Component[] components = new Component[7];
for(int i = 0; i < components.length; i++){
   TextView mt = (TextView) v.findViewById(getResources().getIdentifier("mt" + (i+1), "id", getPackageName()));
   TextView tid = (TextView) v.findViewById(getResources().getIdentifier("tid" + (i+1), "id", getPackageName()));
   ImageView img = (ImageView) v.findViewById(getResources().getIdentifier("imageView" + (i+1), "id", getPackageName()));
   components[i] = new Component(mt, tid, img); 
}
....

And to access those you can use something like this

Component c2 = components[3];
c2.mt.setText(......);

score 0 · Answer 3 · answered Oct 28 '17 at 13:27

If the TextView's are listed in the correct order in your XML layout you can do something like this, assuming they are contained in a RelativeLayout but it should work the same for other Layout Class.

  RelativeLayout mLayout = (RelativeLayout) findViewById(R.id.relLayout1);
  ArrayList<TextView> mTextViews = new ArrayList<>();

  for (int i = 0; i < mLayout.getChildCount(); i++) {
      View view = mLayout.getChildAt(i);
      if (view instanceof TextView)
            mTextViews.add((TextView)view);
  }

To get later one of the TexView myTextView = mTextViews.get[index];

Findviewbyid() in for loop

3 Answers3