Android wear WearableListView ImageView selector

问题

I am trying to create a list view as follows:-

Now, I have made the list view work successfully using the WearableListView adapter. However, I am using static images in the ImageView. What I want is to create this gray and blue kind of animation when a particular list element is focused while scrolling. How do I do that? I tried using a selector xml file for the ImageView but it seems this ListView doesnt make use of this selector(android:state-focused, selected, pressed-nothing works). Any idea how do I get what I want? Hope I made my question clear. Thanks.

回答1:

Yes you are right, image selector doesn't work, why? I don't know exactly and we don't have any documentation on it to read.

But fortunately I have implemented this scenario successfully and it's almost similar to the default settings screen.

For workaround, I have set circle color inside below methods:

1. onScaleUpStart() - Set circle color for selected item
2. onScaleDownStart() - Set circle color for non-selected items.

I have taken CircleImageView and TextView inside my item layout. Example code could be:

private final class MyItemView extends FrameLayout implements WearableListView.Item {

    final CircledImageView image;
    final TextView text;
    private float mScale;
    private final int mFadedCircleColor;
    private final int mChosenCircleColor;

    public MyItemView(Context context) {
        super(context);
        View.inflate(context, R.layout.wearablelistview_item, this);
        image = (CircledImageView) findViewById(R.id.image);
        text = (TextView) findViewById(R.id.text);
        mFadedCircleColor = getResources().getColor(android.R.color.darker_gray);
        mChosenCircleColor = getResources().getColor(android.R.color.holo_blue_dark);
    }

    @Override
    public float getProximityMinValue() {
        return mDefaultCircleRadius;
    }

    @Override
    public float getProximityMaxValue() {
        return mSelectedCircleRadius;
    }

    @Override
    public float getCurrentProximityValue() {
        return mScale;
    }

    @Override
    public void setScalingAnimatorValue(float value) {
        mScale = value;
        image.setCircleRadius(mScale);
        image.setCircleRadiusPressed(mScale);
    }

    @Override
    public void onScaleUpStart() {
        image.setAlpha(1f);
        text.setAlpha(1f);
        image.setCircleColor(mChosenCircleColor);
    }

    @Override
    public void onScaleDownStart() {
        image.setAlpha(0.5f);
        text.setAlpha(0.5f);
        image.setCircleColor(mFadedCircleColor);
    }
}

回答2:

New update brings WearableListView.OnCenterProximityListener alternative of WearableListView.Item to implement Wearable list view with selector,

It has two methods to implement:

1. onCenterPosition

2. onNonCenterPosition

   public class WearableListItemLayout extends LinearLayout implements WearableListView.OnCenterProximityListener {
   
   private CircledImageView image;
   private TextView text;
   
   public WearableListItemLayout(Context context) {
       this(context, null);
   }
   
   public WearableListItemLayout(Context context, AttributeSet attrs) {
       this(context, attrs, 0);
   }
   
   public WearableListItemLayout(Context context, AttributeSet attrs, int defStyle) {
       super(context, attrs, defStyle);
   }
   
   @Override
   protected void onFinishInflate() {
       super.onFinishInflate();
       image = (CircledImageView) findViewById(R.id.image);
       text = (TextView) findViewById(R.id.name);
   }
   
   @Override
   public void onCenterPosition(boolean b) {
       image.setAlpha(1f);
       image.setBackgroundResource(R.drawable.blue_oval);
       text.setAlpha(1f);
   }
   
   @Override
   public void onNonCenterPosition(boolean b) {
       image.setAlpha(0.5f);
       image.setBackgroundResource(R.drawable.gray_oval);
       text.setAlpha(0.5f);
   }
   }
   

来源：https://stackoverflow.com/questions/25106866/android-wear-wearablelistview-imageview-selector