Android custom attributes not showing

Question

I've seen a lot of posts with people wanting to know how to get custom attributes for a custom component but that is not my question. I have created a custom component and I'm trying to add attributes but when I add the namespace at the top of my xml file it only finds two random custom attributes "paddingEnd" and "paddingStart".

<resources>
    <declare-styleable name="menu_item_attrs">
        <attr name="imageId" format="integer" />
        <attr name="menuText" format="string" />
    </declare-styleable>
</resources>

This is attrs.xml file.

public MenuListItem(Context context, AttributeSet set) {
    super(context, set);

    TypedArray a = context.obtainStyledAttributes(set, R.styleable.menu_item_attrs);
    if (a == null) {
        return;
    }
    CharSequence s = a.getString(R.styleable.menu_item_attrs_menuText);
    if (s != null) {
        // do something
    }
}

This is the constructor in my custom class.

        <LinearLayout
            xmlns:custom="http://schemas.android.com/apk/res-auto"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:id="@+id/expanding_layout"
            android:background="#029eed">

            <aaron.testappanim.MenuListItem
                android:layout_height="wrap_content"
                android:layout_width="wrap_content"/>
        </LinearLayout>

This is my component in use. I want to add values to "imageId" and "menuText" but they aren't available. The only things that show are padding related as shown below.

Any ideas guys?

Answer 1

Found the solution.

As it happens you need to have the styleable name the same as your class name.

<resources>
    <declare-styleable name="MenuListItem">
        <attr name="my_custom_attribute" format="integer" />
    </declare-styleable>
</resources>

Many many posts on this subject are wrong in that case as I can see plenty with the styles name being completely different.

Hopefully this can stop someone else falling into this trap.

Cheers

Answer 2

My solution was: In the attr.xml file, you may have declared your custom attribute as follows

<declare-styleable name="IDEditText"> <attr name="customFont" format="string"/> </declare-styleable>

Here, the name field of declare-styleable must be the name of the custom view. Then it will show in the suggestions.

In mycase my custom view name is IDEditText , hence the declare-styleable name="IDEditText"

Answer 3

Although this post is a bit old, just for the sake of information I will share my case.

I defined a custom attribute file named attrs.xml to use with MaterialCardView:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="DeviceMaterialCardView">
        <attr name="state_none" format="boolean"/>
        <attr name="state_favorite" format="boolean"/>
        <attr name="state_dragging" format="boolean"/>
    </declare-styleable>
</resources>

I use dragging attr to change the stroke color of the cardview with this selector:

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

    <item android:color="?attr/colorSecondary" himtec:durum_surukle="true"/>
    <item android:color="?attr/colorSecondary" android:state_activated="true"/>
    <item android:alpha="0.2" android:color="?attr/colorOnBackground"/>
</selector>

And finally I have the custom class named DeviceMaterialCardView . Now the custom attribute has the same name as the custom class. But yet I am getting compilation error while compiling the him_stroke_color xml file:

/home/Projeler/PK-BLE-RF/Android/Uygulama/PK0101BLE/app/src/main/res/color/him_stroke_color.xml:6: AAPT: error: attribute com.himtec.himtec_kontrol:state_dragging not found.

I'm still stuck and can't figure out how to get around this.