Question

So I have written a ‘multi-sliding drawer’ widget, which works like Slidingdrawer except it allows up to 4 ‘drawers’. However, I would really prefer to make this ‘n-drawers’, but the issue I have is with the parameters in xml. Currently, I am passing in the handles/contents via:

ns:handle1="@+id/slideHandleButton1"
ns:content1="@+id/contentLayout1"
ns:handle2="@+id/slideHandleButton2"
ns:content2="@+id/contentLayout2"
ns:handle3="@+id/slideHandleButton3"
ns:content3="@+id/contentLayout3"       

but obviously there is some redundancy here. I originally thought I could just use ‘getChild(i)’ to cycle through the children and add them internally, but my understanding is that the getChild method returns children in visual order, not the order they were added in xml. So what I want to do now is something like:

ns:handles="@id/contentLayout1,@id/contentLayout2,@id/contentLayout13"

which would allow an arbitrary number of drawers. Is this possible? Or is there another good solution to this issue?

Answer 1

You can define your widget to have parameters (say, handles andcontents) that each takes a reference to an array. You can define the arrays using the standard notation:

res/values/arrays.xml

<array name="my_widget_layouts">
    <item>@layout/contentLayout1</item>
    <item>@layout/contentLayout2</item>
    . . .
</array>

<array name="my_widget_buttons">
    <item>@+id/slideHandleButton1</item>
    <item>@+id/slideHandleButton2</item>
    . . .
</array>

inside some layout:

<com.example.MyWidget
    ns:contents="@array/my_widget_layouts"
    ns:handles="@array/my_widget/buttons"
    . . .
    />

Then in the Java code when you construct your widget:

MyWidget(Context context, AttributeSet attrs) {
    Resources res = getResources();
    TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyWidget);
    // Get the ID of the array containing the content layout IDs for this widget
    int contentsId = a.getResourceId(R.styleable.MyWidget_contents, 0);
    if (contentsId > 0) {
        // array of layouts specified
        TypedArray ta = res.obtainTypedArray(contentsId);
        int n = ca.length();
        mContentLayoutIds = new int[n];
        for (int i = 0; i < n; ++i) {
            mContentLayoutIds[i] = ta.getResourceId(i, 0);
            // error check: should never be 0
        }
        ta.recycle();
    }
    // similar code to retrieve the button IDs
    if (mContentLayoutIds.length != mHandleIds.length) {
        // content layout and button arrays not same length: throw an exception
    }
    . . .
    a.recycle();
    . . .
}