Android EditText in merge layout cascade copying issue

Question

to speed up the development of an App I created this editText with a label attached.

This is the class:

public class EditTextWithLabel extends LinearLayout {

    @InjectView(R.id.text_edittext_with_label)
    protected TextView label;

    @InjectView(R.id.edittext_edittext_with_label)
    protected EditText editText;

    public EditTextWithLabel(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
        getAttributes(context, attrs);
    }

    ...

    private void init(Context context) {
        LayoutInflater.from(context).inflate(R.layout.layout_edittext_with_label, this, true);
        ButterKnife.inject(this);

        setOrientation(VERTICAL);
    }

    private void getAttributes(Context context, AttributeSet attrs) {
        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.EditTextWithLabel, 0, 0);

        try {

            CharSequence label = a.getText(R.styleable.EditTextWithLabel_label);
            if (!TextUtils.isEmpty(label))
                setLabel(label);

            CharSequence text = a.getText(R.styleable.EditTextWithLabel_android_text);
            if (!TextUtils.isEmpty(text))
                setText(text);

            CharSequence hint = a.getText(R.styleable.EditTextWithLabel_android_hint);
            if (!TextUtils.isEmpty(hint))
                setHint(hint);

            int maxLength = a.getInt(R.styleable.EditTextWithLabel_android_maxLength, -1);
            if (maxLength > 0)
                setMaxLength(maxLength);

            int type = a.getInt(R.styleable.EditTextWithLabel_android_inputType, InputType.TYPE_CLASS_TEXT);
            setInputType(type);

        } finally {
            a.recycle();
        }
    }

    ...
}

And this is xml:

<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android">

    <TextView
        android:id="@+id/text_edittext_with_label"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="@dimen/edit_text_radius"
        android:paddingBottom="5dp"
        android:text="@string/username"
        android:textColor="@color/text"
        android:textSize="@dimen/text_edit_text"
        />

    <EditText
        android:id="@+id/edittext_edittext_with_label"
        style="@style/EditText"
        android:inputType="textEmailAddress"/>

</merge>

I found out that if I put more of these in a fragment, when I restore it ALL the editTexts show the text that is wrote in the last one.

I cannot explain this behavior, so I hope that somebody could enlight me.

Thank you

EDIT

Thanks to J. Dow answer I was able to solve the issue, I've added at the end of the init method this code:

label.setId((int) System.currentTimeMillis());
editText.setId((int) System.currentTimeMillis());

This randomized the ids enough to avoid the issue.

score 0 · Accepted Answer · answered Apr 08 '16 at 16:25

0

What merge is doing is basically a simple include. So your final Layout will include multiple "copies" of your EditText.

From the Android documentation:

Note: In order for the Android system to restore the state of the views in our activity, each view must have a unique ID, supplied by the android:id attribute.

http://developer.android.com/training/basics/activity-lifecycle/recreating.html

Thus, when restoring your merged layout, the Android system will encounter multiple EditTexts with the same id and therefore restore each of them with the same state.

answered Apr 08 '16 at 16:25

J. Dow

563
3
13

Thanks, you've been very clear, so isn't there a way to optimize the layouts using always the same object? – Marco Fedele Apr 08 '16 at 16:29
1

Sure. If you want to reuse the same layout within the same fragment or activity layout, you just have to make sure that every view has a unique id within this layout. You can also overwrite the save/restore methods, but this is probably unnecessary complicated. http://stackoverflow.com/questions/1714297/android-view-setidint-id-programmatically-how-to-avoid-id-conflicts – J. Dow Apr 08 '16 at 16:37

Android EditText in merge layout cascade copying issue

1 Answers1