AltitudeTape.java

package org.schmivits.airball.display.altitude;

import android.content.res.AssetManager;
import android.content.res.Resources;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;

import org.schmivits.airball.base.R;
import org.schmivits.airball.display.DisplayConfiguration;
import org.schmivits.airball.util.ValueModel;
import org.schmivits.airball.widget.Container;
import org.schmivits.airball.widget.FilledPolygon;
import org.schmivits.airball.widget.Rectangle;
import org.schmivits.airball.widget.TiledImage;
import org.schmivits.airball.widget.Widget;

public class AltitudeTape extends Container {

    public interface Model {
        ValueModel<Float> getAltitude();
    }

    private final Model mModel;
    private final AltitudeTapeCore mTape;
    private final Widget mInvalidImage;

    /**
     * Create an AltitudeTape.
     */
    public AltitudeTape(
            DisplayConfiguration config,
            Resources res, AssetManager assets,
            float x, float y, float w, float h,
            final Model model) {
        mModel = model;

        moveTo(x, y);
        sizeTo(w, h);

        float invalidWidth = (float) Math.floor(w / 8);

        mTape = new AltitudeTapeCore(
                config, assets,
                config.mPointerToScaleOffset, 0f, w - config.mPointerToScaleOffset, h,
                new AltitudeTapeCore.Model() {
                    @Override
                    public float getAltitude() {
                        return model.getAltitude().isValid() ? model.getAltitude().getValue() : 0f;
                    }
                });

        Widget pointerSymbol = new FilledPolygon(
                new float[][]{
                        {0.0f, 0.0f},
                        {1.0f, 0.5f},
                        {0.0f, 1.0f},
                },
                config.mPointerColor);
        pointerSymbol.sizeTo(config.mPointerShapeSize, config.mPointerShapeSize);

        Widget pointerLine = new Rectangle(config.mPointerColor);
        pointerLine.sizeTo(w, config.mThickLineThickness);

        pointerSymbol.moveTo(
                0, (getHeight() - pointerSymbol.getHeight()) / 2f);
        pointerLine.moveTo(
                0, (getHeight() - pointerLine.getHeight()) / 2f);

        mInvalidImage = new TiledImage(BitmapFactory.decodeResource(res, R.drawable.error_texture));
        mInvalidImage.moveTo(config.mPointerToScaleOffset, 0f);
        mInvalidImage.sizeTo(invalidWidth, h);

        mChildren.add(mTape);
        mChildren.add(mInvalidImage);
        mChildren.add(pointerSymbol);
        mChildren.add(pointerLine);
    }

    @Override
    protected void drawContents(Canvas canvas) {
        if (!mModel.getAltitude().isValid()) {
            mInvalidImage.setVisible(true);
            mTape.setVisible(false);
        } else {
            mInvalidImage.setVisible(false);
            mTape.setVisible(true);
        }
        super.drawContents(canvas);
    }
}