代码实现Launcher3抽屉模式高斯模糊

以下是一个简单的代码实现 Launcher3 抽屉模式高斯模糊的示例，仅供参考：

1. 创建 RenderScript 脚本文件 GaussianBlur.rs：

#pragma version(1)
#pragma rs java_package_name(com.example.launcher3)

rs_allocation inputAllocation;
rs_allocation outputAllocation;

int width;
int height;
int radius;

void root(const uchar4 *v_in, uchar4 *v_out, const void *usrData, uint32_t x, uint32_t y) {
    float4 sum = 0;
    float wsum = 0;
    int r = radius;

    for (int i = -r; i <= r; i++) {
        for (int j = -r; j <= r; j++) {
            if ((x + i) >= 0 && (x + i) < width && (y + j) >= 0 && (y + j) < height) {
                float4 color = rsUnpackColor8888(*(rsGetElementAt_uchar4(inputAllocation, x + i, y + j)));
                float weight = exp(-(i * i + j * j) / (2.0f * r * r));
                sum += color * weight;
                wsum += weight;
            }
        }
    }

    *v_out = rsPackColorTo8888(sum / wsum);
}

2. 在 Java 代码中加载 RenderScript 脚本文件：

private RenderScript mRenderScript;
private ScriptC_GaussianBlur mScriptGaussianBlur;

private void initRenderScript() {
    mRenderScript = RenderScript.create(this);
    mScriptGaussianBlur = new ScriptC_GaussianBlur(mRenderScript, getResources(), R.raw.gaussianblur);
}

3. 创建一个 Bitmap 对象，将抽屉中显示的内容绘制到这个 Bitmap 上：

private Bitmap getDrawerBitmap() {
    int width = mDrawerList.getWidth();
    int height = mDrawerList.getHeight();
    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    mDrawerList.draw(canvas);
    return bitmap;
}

4. 将 Bitmap 作为输入数据，调用 RenderScript 对象中的函数进行高斯模糊处理：

private Bitmap blurBitmap(Bitmap inputBitmap, int radius) {
    int width = inputBitmap.getWidth();
    int height = inputBitmap.getHeight();
    Bitmap outputBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Allocation inputAllocation = Allocation.createFromBitmap(mRenderScript, inputBitmap);
    Allocation outputAllocation = Allocation.createFromBitmap(mRenderScript, outputBitmap);
    mScriptGaussianBlur.set_inputAllocation(inputAllocation);
    mScriptGaussianBlur.set_outputAllocation(outputAllocation);
    mScriptGaussianBlur.set_width(width);
    mScriptGaussianBlur.set_height(height);
    mScriptGaussianBlur.set_radius(radius);
    mScriptGaussianBlur.forEach_root(inputAllocation, outputAllocation);
    outputAllocation.copyTo(outputBitmap);
    return outputBitmap;
}

5. 将处理后的 Bitmap 显示在抽屉中：

private void showBlurredDrawer() {
    Bitmap drawerBitmap = getDrawerBitmap();
    Bitmap blurredBitmap = blurBitmap(drawerBitmap, 10);
    mDrawerBackground.setImageDrawable(new BitmapDrawable(getResources(), blurredBitmap));
    mDrawerLayout.openDrawer(mDrawerList);
}

以上是一个简单的示例，实际实现中可能需要根据具体情况进行修改和优化。