Question

我正在开发一个Android应用程序，我想减少我的图标。我尝试了不同的方法，但每次返回的drawable具有低密度.. 然而，当我在photoshop上调整相同的图像时，它保持了良好的密度。以下代码是我找到的最好的代码。

你能帮我改进一下吗？

 public class MainActivity extends Activity {


@Override
protected void onCreate(Bundle savedInstanceState) {


    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    ImageView newImage = (ImageView) findViewById(R.id.image);

    Bitmap unscaledBitmap = decodeResource(getBaseContext().getResources(),R.drawable.test2, 120, 120, ScalingLogic.FIT);

            newImage.setImageBitmap(createScaledBitmap(unscaledBitmap, 120, 120, ScalingLogic.FIT));
    newImage.setImageBitmap(createScaledBitmap(unscaledBitmap, 120, 120, ScalingLogic.FIT));



}

public static Bitmap decodeResource(Resources res, int resId, int dstWidth, int dstHeight,
        ScalingLogic scalingLogic) {
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(res, resId, options);
        options.inJustDecodeBounds = false;
        options.inSampleSize = calculateSampleSize(options.outWidth, options.outHeight, dstWidth,
                dstHeight, scalingLogic);
        Bitmap unscaledBitmap = BitmapFactory.decodeResource(res, resId, options);

        return unscaledBitmap;
    }


    public static Bitmap createScaledBitmap(Bitmap unscaledBitmap, int dstWidth, int dstHeight,
    ScalingLogic scalingLogic) {
        Rect srcRect = calculateSrcRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Rect dstRect = calculateDstRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Bitmap scaledBitmap = Bitmap.createBitmap(dstRect.width(), dstRect.height(),
                Bitmap.Config.RGB_565);
        Canvas canvas = new Canvas(scaledBitmap);
        canvas.drawBitmap(unscaledBitmap, srcRect, dstRect, new Paint(Paint.FILTER_BITMAP_FLAG));

        return scaledBitmap;
    }


    public static enum ScalingLogic {
        CROP, FIT
    }


    public static int calculateSampleSize(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
    ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcWidth / dstWidth;
            } else {
                return srcHeight / dstHeight;
            }
        } else {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcHeight / dstHeight;
            } else {
                return srcWidth / dstWidth;
            }
        }
    }


    public static Rect calculateSrcRect(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
    ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.CROP) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                final int srcRectWidth = (int)(srcHeight * dstAspect);
                final int srcRectLeft = (srcWidth - srcRectWidth) / 2;
                return new Rect(srcRectLeft, 0, srcRectLeft + srcRectWidth, srcHeight);
            } else {
                final int srcRectHeight = (int)(srcWidth / dstAspect);
                final int scrRectTop = (int)(srcHeight - srcRectHeight) / 2;
                return new Rect(0, scrRectTop, srcWidth, scrRectTop + srcRectHeight);
            }
        } else {
            return new Rect(0, 0, srcWidth, srcHeight);
        }
    }


    public static Rect calculateDstRect(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
    ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return new Rect(0, 0, dstWidth, (int)(dstWidth / srcAspect));
            } else {
                return new Rect(0, 0, (int)(dstHeight * srcAspect), dstHeight);
            }
        } else {
            return new Rect(0, 0, dstWidth, dstHeight);
        }
    }

    }

Answer 1

我认为您需要使用9-patch图像来定义可伸缩区域。这些区域在区域周围的特殊1像素宽边框中定义，因为除了图像的其余部分之外，自定义绘制的按钮在其边界被拉伸时可能看起来扭曲和像素化9-补丁图像分别缩放。这对于具有不同分辨率和宽高比的较小屏幕的移动设备来说是很方便的。看一下这个example

Android：调整drawable的大小

1 个答案: