修改 Android 可绘制对象的颜色

我希望能够使用相同的可绘制对象来表示两者：

and

作为相同的可绘制对象，并根据某些编程值重新为可绘制对象着色，以便最终用户可以重新主题化界面。

做这个的最好方式是什么？我已经尝试过（并重复使用了其中的图标）这个以前的S.O.问题 https://stackoverflow.com/questions/4354939/understanding-the-use-of-colormatrix-and-colormatrixcolorfilter-to-modify-a-draw但我不能将这种变化表示为简单的色调变化，因为它的饱和度和明度也有所不同。

最好将我想要更改的区域的图标存储为全白色吗？还是透明的？或者其他纯色？

是否有某种方法可以让您根据红色图标的颜色和蓝色图标的颜色之间的差异计算出矩阵？

因此，经过大量的试验和错误，阅读不同的文章，最重要的是，通过 API 演示（ColorFilters.java - 在 com.example.android.apis.graphics 中找到）我找到了解决方案。

对于实体图像，我发现最好使用颜色滤镜 PorterDuff.Mode.SRC_ATOP 因为它将颜色覆盖在源图像的顶部，允许您将颜色更改为您正在寻找的确切颜色。

对于更复杂的图像（如上面的图像），我发现最好的办法是将整个图像着色为白色（FFFFFF），这样当您执行 PorterDuff.Mode.MULTIPLY 时，您最终会得到正确的颜色，并且图像中的所有黑色 (000000) 将保持黑色。

colorfilters.java 向您展示了在画布上绘图时是如何完成的，但如果您需要的只是为可绘制对象着色，那么这将起作用：

COLOR2 = Color.parseColor("#FF"+getColor());
Mode mMode = Mode.SRC_ATOP;
Drawable d = mCtx.getResources().getDrawable(R.drawable.image);
d.setColorFilter(COLOR2,mMode)

我使用一些 API 演示代码创建了一个演示活动，在每种颜色滤镜模式之间进行交换，以在不同的情况下尝试它们，并发现它非常有价值，所以我想我将其发布在这里。

public class ColorFilters extends GraphicsActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new SampleView(this));

}

private static class SampleView extends View {
    private Activity mActivity;
    private Drawable mDrawable;
    private Drawable[] mDrawables;
    private Paint mPaint;
    private Paint mPaint2;
    private float mPaintTextOffset;
    private int[] mColors;
    private PorterDuff.Mode[] mModes;
    private int mModeIndex;
    private Typeface futura_bold;
    private AssetManager assets;

    private static void addToTheRight(Drawable curr, Drawable prev) {
        Rect r = prev.getBounds();
        int x = r.right + 12;
        int center = (r.top + r.bottom) >> 1;
        int h = curr.getIntrinsicHeight();
        int y = center - (h >> 1);

        curr.setBounds(x, y, x + curr.getIntrinsicWidth(), y + h);
    }

    public SampleView(Activity activity) {
        super(activity);
        mActivity = activity;
        Context context = activity;
        setFocusable(true);

        /**1. GET DRAWABLE, SET BOUNDS */
        assets = context.getAssets();
        mDrawable = context.getResources().getDrawable(R.drawable.roundrect_gray_button_bg_nine);
        mDrawable.setBounds(0, 0, mDrawable.getIntrinsicWidth(), mDrawable.getIntrinsicHeight());

        mDrawable.setDither(true);

        int[] resIDs = new int[] {
            R.drawable.roundrect_gray_button_bg,
            R.drawable.order_button_white,
            R.drawable.yellowbar
        };
        mDrawables = new Drawable[resIDs.length];
        Drawable prev = mDrawable;
        for (int i = 0; i < resIDs.length; i++) {
            mDrawables[i] = context.getResources().getDrawable(resIDs[i]);
            mDrawables[i].setDither(true);
            addToTheRight(mDrawables[i], prev);
            prev = mDrawables[i];
        }

        /**2. SET Paint for writing text on buttons */
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setTextSize(16);
        mPaint.setTextAlign(Paint.Align.CENTER);

        mPaint2 = new Paint(mPaint);
        /** Calculating size based on font */
        futura_bold = Typeface.createFromAsset(assets,
                "fonts/futurastd-bold.otf");
        //Determine size and offset to write text in label based on font size.
        mPaint.setTypeface(futura_bold);
        Paint.FontMetrics fm = mPaint.getFontMetrics();
        mPaintTextOffset = (fm.descent + fm.ascent) * 0.5f;

        mColors = new int[] {
            0,
            0xFFA60017,//WE USE THESE
            0xFFC6D405,
            0xFF4B5B98,
            0xFF656565,
            0xFF8888FF,
            0xFF4444FF,
        };

        mModes = new PorterDuff.Mode[] {
            PorterDuff.Mode.DARKEN,
            PorterDuff.Mode.DST,
            PorterDuff.Mode.DST_ATOP,
            PorterDuff.Mode.DST_IN,
            PorterDuff.Mode.DST_OUT,
            PorterDuff.Mode.DST_OVER,
            PorterDuff.Mode.LIGHTEN,
            PorterDuff.Mode.MULTIPLY,
            PorterDuff.Mode.SCREEN,
            PorterDuff.Mode.SRC,
            PorterDuff.Mode.SRC_ATOP,
            PorterDuff.Mode.SRC_IN,
            PorterDuff.Mode.SRC_OUT,
            PorterDuff.Mode.SRC_OVER,
            PorterDuff.Mode.XOR
        };
        mModeIndex = 0;

        updateTitle();
    }

    private void swapPaintColors() {
        if (mPaint.getColor() == 0xFF000000) {
            mPaint.setColor(0xFFFFFFFF);
            mPaint2.setColor(0xFF000000);
        } else {
            mPaint.setColor(0xFF000000);
            mPaint2.setColor(0xFFFFFFFF);
        }
        mPaint2.setAlpha(0);
    }

    private void updateTitle() {
        mActivity.setTitle(mModes[mModeIndex].toString());
    }

    private void drawSample(Canvas canvas, ColorFilter filter) {
        /** Create a rect around bounds, ensure size offset */
        Rect r = mDrawable.getBounds();
        float x = (r.left + r.right) * 0.5f;
        float y = (r.top + r.bottom) * 0.5f - mPaintTextOffset;

        /**Set color filter to selected color 
         * create canvas (filled with this color)
         * Write text using paint (new color)
         */
        mDrawable.setColorFilter(filter);
        mDrawable.draw(canvas);
        /** If the text doesn't fit in the button, make the text size smaller until it does*/
        final float size = mPaint.measureText("Label");
        if((int) size > (r.right-r.left)) {
            float ts = mPaint.getTextSize();
            Log.w("DEBUG","Text size was"+ts);
            mPaint.setTextSize(ts-2);
        }
        canvas.drawText("Sausage Burrito", x, y, mPaint);
        /** Write the text and draw it onto the drawable*/

        for (Drawable dr : mDrawables) {
            dr.setColorFilter(filter);
            dr.draw(canvas);
        }
    }

    @Override protected void onDraw(Canvas canvas) {
        canvas.drawColor(0xFFCCCCCC);            

        canvas.translate(8, 12);
        for (int color : mColors) {
            ColorFilter filter;
            if (color == 0) {
                filter = null;
            } else {
                filter = new PorterDuffColorFilter(color,
                                                   mModes[mModeIndex]);
            }
            drawSample(canvas, filter);
            canvas.translate(0, 55);
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float x = event.getX();
        float y = event.getY();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                break;
            case MotionEvent.ACTION_MOVE:
                break;
            case MotionEvent.ACTION_UP:
                // update mode every other time we change paint colors
                if (mPaint.getColor() == 0xFFFFFFFF) {
                    mModeIndex = (mModeIndex + 1) % mModes.length;
                    updateTitle();
                }
                swapPaintColors();
                invalidate();
                break;
            }
        return true;
        }
    }
}

如果您想对其进行测试，可以直接从 API 演示活动复制其他两个依赖项 GraphicsActivity.java 和 PictureLayout.java。