Question

在我的应用程序中，我必须为通知设置一个大图标。 LargeIcon必须是一个Bitmap，我的drawable是矢量图像（Android中的新功能，请参阅this link）问题是，当我尝试解码作为矢量图像的资源时，我得到一个null返回。

以下是代码示例：

if (BitmapFactory.decodeResource(arg0.getResources(), R.drawable.vector_menu_objectifs) == null)
        Log.d("ISNULL", "NULL");
    else
        Log.d("ISNULL", "NOT NULL");

在这个示例中，当我用“普通”图像替换R.drawable.vector_menu_objectifs时，例如png为例，结果不为空（我得到正确的位图）有什么我想念的吗？

Answer 1

检查API：17,21,23

public static Bitmap getBitmapFromVectorDrawable(Context context, int drawableId) {
    Drawable drawable = ContextCompat.getDrawable(context, drawableId);
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
        drawable = (DrawableCompat.wrap(drawable)).mutate();
    }

    Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
            drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    drawable.draw(canvas);

    return bitmap;
}

<强>更新

Project gradle：

dependencies {
        classpath 'com.android.tools.build:gradle:2.2.0-alpha5'
    }

模块gradle：

android {
    compileSdkVersion 23
    buildToolsVersion '23.0.3'
    defaultConfig {
        minSdkVersion 16
        targetSdkVersion 23
        vectorDrawables.useSupportLibrary = true
    }
    ...
}
...

Answer 2

您可以使用以下方法：

@TargetApi(Build.VERSION_CODES.LOLLIPOP)
private static Bitmap getBitmap(VectorDrawable vectorDrawable) {
    Bitmap bitmap = Bitmap.createBitmap(vectorDrawable.getIntrinsicWidth(),
            vectorDrawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    vectorDrawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    vectorDrawable.draw(canvas);
    return bitmap;
}

我有时会与之合并：

private static Bitmap getBitmap(Context context, int drawableId) {
    Drawable drawable = ContextCompat.getDrawable(context, drawableId);
    if (drawable instanceof BitmapDrawable) {
        return ((BitmapDrawable) drawable).getBitmap();
    } else if (drawable instanceof VectorDrawable) {
        return getBitmap((VectorDrawable) drawable);
    } else {
        throw new IllegalArgumentException("unsupported drawable type");
    }
}

Answer 3

根据之前的答案，可以简化它，以匹配VectorDrawable和BitmapDrawable，并至少与API 15兼容。

public static Bitmap getBitmapFromDrawable(Context context, @DrawableRes int drawableId) {
    Drawable drawable = AppCompatResources.getDrawable(context, drawableId);

    if (drawable instanceof BitmapDrawable) {
        return ((BitmapDrawable) drawable).getBitmap();
    } else if (drawable instanceof VectorDrawableCompat || drawable instanceof VectorDrawable) {
        Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
        drawable.draw(canvas);

        return bitmap;
    } else {
        throw new IllegalArgumentException("unsupported drawable type");
    }
}

然后你必须添加你的gradle文件：

android {
    defaultConfig {
        vectorDrawables.useSupportLibrary = true
    }
}

在Lollipop之前，它将使用VectorDrawableCompat，在Lollipop上它将使用VectorDrawable。

修改

我在@ user3109468

的评论后编辑了这个条件

Answer 4

如果您愿意将Android KTX用于Kotlin，则可以使用扩展方法Drawable#toBitmap()来达到与其他答案相同的效果：

val bitmap = AppCompatResources.getDrawable(requireContext(), drawableId).toBitmap()

或

val bitmap = AppCompatResources.getDrawable(context, drawableId).toBitmap()

要添加此扩展方法和其他有用的扩展方法，您需要将以下内容添加到模块级build.gradle

repositories {
    google()
}

dependencies {
    implementation 'androidx.core:core-ktx:1.0.0-alpha1'
}

链接到扩展方法的源here。

请注意，这将适用于Drawable的任何子类，如果Drawable是BitmapDrawable，它将快捷使用基础{{1} }。

Answer 5

感谢@Alexey

以下是使用[{1}}

扩展程序的Kotlin版本

Context

fun Context.getBitmapFromVectorDrawable(drawableId: Int): Bitmap? { var drawable = ContextCompat.getDrawable(this, drawableId) ?: return null if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) { drawable = DrawableCompat.wrap(drawable).mutate() } val bitmap = Bitmap.createBitmap( drawable.intrinsicWidth, drawable.intrinsicHeight, Bitmap.Config.ARGB_8888) ?: return null val canvas = Canvas(bitmap) drawable.setBounds(0, 0, canvas.width, canvas.height) drawable.draw(canvas) return bitmap }中的用法示例：

Activity

Answer 6

使用以下代码转换具有正确纵横比的图像（例如，用于通知图标）：

public static Bitmap getBitmapFromVector(Context context, int drawableId) {
    Drawable drawable = ContextCompat.getDrawable(context, drawableId);
    int width = drawable.getIntrinsicWidth();
    int height = drawable.getIntrinsicHeight();
    Bitmap bitmap;
    if (width < height) {    //make a square
        bitmap = Bitmap.createBitmap(height, height, Bitmap.Config.ARGB_8888);
    } else {
        bitmap = Bitmap.createBitmap(width, width, Bitmap.Config.ARGB_8888);
    }
    Canvas canvas = new Canvas(bitmap);
    drawable.setBounds(0, 0,
            drawable.getIntrinsicWidth(),    //use dimensions of Drawable
            drawable.getIntrinsicHeight()
    );
    drawable.draw(canvas);
    return bitmap;
}

Answer 7

Drawable layerDrawable = (Drawable) imageBase.getDrawable();
Bitmap bitmap = Bitmap.createBitmap(layerDrawable.getIntrinsicWidth(),
        layerDrawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
layerDrawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
layerDrawable.draw(canvas);  
imageTeste.setImageBitmap(addGradient(bitmap));

Answer 8

如果您的vector图像intrinsicWidth和intrinsicHeight很小，并且您尝试将位图显示为大视图，那么您将看到结果是模糊的。

在这种情况下，您可以为位图提供新的宽度/高度以获得更好的图像（或者可以在xml中增加矢量大小，但可以使用desireWidth和desireHeight更加灵活）。

private fun getBitmap(drawableId: Int, desireWidth: Int? = null, desireHeight: Int? = null): Bitmap? {
    val drawable = AppCompatResources.getDrawable(context, drawableId) ?: return null
    val bitmap = Bitmap.createBitmap(
        desireWidth ?: drawable.intrinsicWidth,
        desireHeight ?: drawable.intrinsicHeight,
        Bitmap.Config.ARGB_8888
    )
    val canvas = Canvas(bitmap)
    drawable.setBounds(0, 0, canvas.width, canvas.height)
    drawable.draw(canvas)
    return bitmap
}

希望有帮助

Answer 9

如果您希望能够将输出缩放到所需的输出大小，请尝试以下代码段：

fun getBitmapFromVectorDrawable(context: Context, drawableId: Int, outputSize: OutputSize? = null): Bitmap? {
    var drawable = ContextCompat.getDrawable(context, drawableId) ?: return null
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
        drawable = DrawableCompat.wrap(drawable).mutate()
    }

    var targetBitmap: Bitmap
    if (outputSize != null) {
        targetBitmap = Bitmap.createBitmap(outputSize.width,
                outputSize.height, Bitmap.Config.ARGB_8888)
    } else {
        targetBitmap = Bitmap.createBitmap(drawable.intrinsicWidth,
            drawable.intrinsicHeight, Bitmap.Config.ARGB_8888)
    }

    val canvas = Canvas(targetBitmap)
    val scaleX =  targetBitmap.width.toFloat()/drawable.intrinsicWidth.toFloat()
    val scaleY =  targetBitmap.height.toFloat()/drawable.intrinsicHeight.toFloat()
    canvas.scale(scaleX, scaleY)
    drawable.draw(canvas)

    return targetBitmap
}

class OutputSize(val width: Int, val height: Int)

Answer 10

在API 16上进行了测试-具有矢量可绘制对象的JellyBean

public static Bitmap getBitmapFromVectorDrawable(Context context, int drawableId) {
    Drawable drawable = AppCompatResources.getDrawable(context, drawableId);
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
        drawable = (DrawableCompat.wrap(drawable)).mutate();
    }

    Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
            drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    drawable.draw(canvas);

    return bitmap;

感谢所有人！

Answer 11

这将为您提供所需大小的位图。另外，它使您可以根据每个图像来保持或不保持透明度，以便在不需要图像的情况下获得更好的性能。

public static Bitmap drawableToBitmap(Resources res, int drawableId,
        int width, int height, boolean keepAlpha) {
    Drawable drawable = res.getDrawable(drawableId);
    Bitmap bmp = createBitmap(width, height, keepAlpha ?
            Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565);
    Canvas cvs = new Canvas(bmp);
    drawable.setBounds(0, 0, width, height);
    drawable.draw(cvs);
    return bmp;
}

Answer 12

对于这里给出的矢量可绘制对象，给定的代码可以帮助我们，但是请记住，如果找不到可绘制对象为NULL，则它可能为空

@Nullable
public static Bitmap drawableToBitmap(Context context, int drawableId) {
    Drawable drawable = ContextCompat.getDrawable(context, drawableId);
    if (drawable != null) {
        int width = drawable.getIntrinsicWidth();
        int height = drawable.getIntrinsicHeight();
        Bitmap bmp = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bmp);
        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
        drawable.draw(canvas);
        return bmp;
    }
    return null;
}

Answer 13

<块引用>

创造Vector to Bitmap的独立乐趣

 //vectorToBitmapMarker
    private fun fromVectorToBitmap(id: Int, color: Int): BitmapDescriptor
    {
        val vectorDrawable: Drawable? = ResourcesCompat.getDrawable(resources, id, null)

        if (vectorDrawable == null)
        {
            d("VTOB","Resource not found!")
            return BitmapDescriptorFactory.defaultMarker()
        }

        val bitmap = Bitmap.createBitmap(
            vectorDrawable.intrinsicWidth,
            vectorDrawable.intrinsicHeight,
            Bitmap.Config.ARGB_8888)

        val canvas = Canvas(bitmap)
        vectorDrawable.setBounds(0,0,canvas.width, canvas.height)
        DrawableCompat.setTint(vectorDrawable, color)
        vectorDrawable.draw(canvas)

        return BitmapDescriptorFactory.fromBitmap(bitmap)

    }

<块引用>

现在对 onMapReady() -> .icon() 进行更改

mMap.addMarker(
       MarkerOptions().position(goa)
           .title("Marker in Goa")
           .draggable(true)
           .icon(fromVectorToBitmap(R.drawable.location, Color.parseColor("#FF0560"))))

从矢量drawable获取位图

13 个答案:

修改