Geek Answers Handbook

FindViewById returns null in user view after bloat

I have a custom RelativeLayoutone and I am inflating the res file. xml. This works fine if I use a custom layout in an XML file and set it as a contentview, but if I try to add it to the code with new LocationItem(this)and addChild(), the method findViewByIdalways returns nullin the custom constructor RelativeLayout.

Here is the code:

public class LocationItem extends RelativeLayout {

private String parcelType;
private int countIntoBox, countFromBox;

private RelativeLayout deliveryContainer, pickupContainer;

private TextView countPickup, countDelivery;

public LocationItem(Context context) {
    this(context, null);
}

public LocationItem(Context context, AttributeSet attrs) {
    this(context, attrs, 0);
}

public LocationItem(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    inflate(getContext(), R.layout.list_item_location, this);
    deliveryContainer = (RelativeLayout) findViewById(R.id.rl_location_delivery_container);
    pickupContainer = (RelativeLayout) findViewById(R.id.rl_location_pickup_container);
    countPickup = (TextView) findViewById(R.id.tv_location_pickup_count);
    countDelivery = (TextView) findViewById(R.id.tv_location_delivery_count);

    countPickup.setOnClickListener(getShowNumberPickerListener());
    countDelivery.setOnClickListener(getShowNumberPickerListener());
}

private OnClickListener getShowNumberPickerListener() {
    return new OnClickListener() {
        @Override
        public void onClick(View view) {
            showNumberPickerDialog(view);
        }
    };
} ...
}

Add custom view to action

mRootLayoutLocations.addView(new LocationItem(this));

The view is overpriced correctly because I see it, but when I try to access the view inside the user view, the application crashes with a NullPointerException.

+5
source
5

, ()

View v = inflate(getContext(), R.layout.list_item_location, this);

v.findViewById. .

:

View v = inflate(getContext(), R.layout.list_item_location, this);
deliveryContainer = (RelativeLayout) v.findViewById(R.id.rl_location_delivery_container);
pickupContainer = (RelativeLayout) v.findViewById(R.id.rl_location_pickup_container);
countPickup = (TextView) v.findViewById(R.id.tv_location_pickup_count);
countDelivery = (TextView) v.findViewById(R.id.tv_location_delivery_count);

countPickup.setOnClickListener(getShowNumberPickerListener());
countDelivery.setOnClickListener(getShowNumberPickerListener());
+2

, .

public class LocationItem extends RelativeLayout {

    private String parcelType;
    private int countIntoBox, countFromBox;

    private RelativeLayout deliveryContainer, pickupContainer;

    private TextView countPickup, countDelivery;

    public LocationItem(Context context) {
        super(context);
        init(context, null, 0);
    }

    public LocationItem(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs, 0);
    }

    public LocationItem(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context, attrs, defStyle);
    }

    private void init(Context context, AttributeSet attrs, int defStyle) {
        inflate(getContext(), R.layout.list_item_location, this);
        deliveryContainer = (RelativeLayout) findViewById(R.id.rl_location_delivery_container);
        pickupContainer = (RelativeLayout) findViewById(R.id.rl_location_pickup_container);
        countPickup = (TextView) findViewById(R.id.tv_location_pickup_count);
        countDelivery = (TextView) findViewById(R.id.tv_location_delivery_count);

        countPickup.setOnClickListener(getShowNumberPickerListener());
        countDelivery.setOnClickListener(getShowNumberPickerListener());
    }

    private OnClickListener getShowNumberPickerListener() {
        return new OnClickListener() {
            @Override
            public void onClick(View view) {
                showNumberPickerDialog(view);
            }
        };
    }

    ...
}
0

, , .

findindViewById(int Id)

Actvity onCreate , /, , .

XML ( )

View rootView=(View) LayoutInflater.from(context).inflate(R.layout.list_item_location);
pickupContainer = (RelativeLayout) rootview.findViewById(R.id.rl_location_pickup_container);
0

public LocationItem(Context context, AttributeSet attrs, int defStyle) {
   super(context, attrs, defStyle);
   this = inflate(getContext(), R.layout.list_item_location,null);
   ...
0

You can try this. Init views in the onFinishInflate () method. This method will be called as the last phase of inflation after adding all child views. This way you can avoid NPE.

0
source

More articles:


All Articles