zsniperx zsniperx - 6 months ago 28
Android Question

Setting a maximum width on a ViewGroup

How do I set the maximum width of a ViewGroup? I am using a

Theme.Dialog
activity, however, this does not look so good when resized to bigger screens, it's also sort of lightweight and I don't want it taking up the whole screen.

I tried this suggestion to no avail. Also, there is no
android:maxWidth
property like some views.

Is there a way to restrict the root LinearLayout so that it is only (for example) 640 dip? I am willing to change to another ViewGroup for this.

Any suggestions?

Answer

One option which is what I did is to extend LinearLayout and override the onMeasure function. For example:

public class BoundedLinearLayout extends LinearLayout {

    private final int mBoundedWidth;

    private final int mBoundedHeight;

    public BoundedLinearLayout(Context context) {
        super(context);
        mBoundedWidth = 0;
        mBoundedHeight = 0;
    }

    public BoundedLinearLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.BoundedView);
        mBoundedWidth = a.getDimensionPixelSize(R.styleable.BoundedView_bounded_width, 0);
        mBoundedHeight = a.getDimensionPixelSize(R.styleable.BoundedView_bounded_height, 0);
        a.recycle();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        // Adjust width as necessary
        int measuredWidth = MeasureSpec.getSize(widthMeasureSpec);
        if(mBoundedWidth > 0 && mBoundedWidth < measuredWidth) {
            int measureMode = MeasureSpec.getMode(widthMeasureSpec);
            widthMeasureSpec = MeasureSpec.makeMeasureSpec(mBoundedWidth, measureMode);
        }
        // Adjust height as necessary
        int measuredHeight = MeasureSpec.getSize(heightMeasureSpec);
        if(mBoundedHeight > 0 && mBoundedHeight < measuredHeight) {
            int measureMode = MeasureSpec.getMode(heightMeasureSpec);
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(mBoundedHeight, measureMode);
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

Then you XML would use the custom class:

<com.yourpackage.BoundedLinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    app:bounded_width="900dp">

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
    />
</com.youpackage.BoundedLinearLayout>

And the attr.xml file entry

<declare-styleable name="BoundedView">
    <attr name="bounded_width" format="dimension" />
    <attr name="bounded_height" format="dimension" />
</declare-styleable>

EDIT: This is the actual code I am using now. This is still not complete but works in most cases.