VectorDrawable 与 GoogleMap BitmapDescriptor

Question

我在使用VectorDrawable，API 5.0+ 为MarkerOptions 创建图标时遇到了谷歌地图BitmapDescriptor 的问题

用于创建的方法：

@NonNull
private BitmapDescriptor getBitmapDescriptor(int id) {
    return BitmapDescriptorFactory.fromResource(id);
}

当id 参数包含 png drawable 时，一切都很好，但是如果我尝试使用在 xml 中定义的VectorDrawable，当googleMap.addMarker(marker)（BitmapDescriptor 不为空）时，应用程序总是崩溃。

11-05 10:15:05.213 14536-14536/xxx.xxxxx.app E/AndroidRuntime: FATAL EXCEPTION: main
    Process: xxx.xxxxx.app, PID: 14536
    java.lang.NullPointerException
        at com.google.a.a.ae.a(Unknown Source)
        at com.google.maps.api.android.lib6.d.dn.<init>(Unknown Source)
        at com.google.maps.api.android.lib6.d.dm.a(Unknown Source)
        at com.google.maps.api.android.lib6.d.ag.<init>(Unknown Source)
        at com.google.maps.api.android.lib6.d.eu.a(Unknown Source)
        at com.google.android.gms.maps.internal.j.onTransact(SourceFile:167)
        at android.os.Binder.transact(Binder.java:380)
        at com.google.android.gms.maps.internal.IGoogleMapDelegate$zza$zza.addMarker(Unknown Source)
        at com.google.android.gms.maps.GoogleMap.addMarker(Unknown Source)
        at xxx.xxxxx.app.ui.details.DetailActivity.lambda$initGoogleMaps$23(DetailActivity.java:387)
        at xxx.xxxxx.app.ui.details.DetailActivity.access$lambda$10(DetailActivity.java)
        at xxx.xxxxx.app.ui.details.DetailActivity$$Lambda$13.onMapReady(Unknown Source)
        at com.google.android.gms.maps.SupportMapFragment$zza$1.zza(Unknown Source)
        at com.google.android.gms.maps.internal.zzl$zza.onTransact(Unknown Source)
        at android.os.Binder.transact(Binder.java:380)
        at com.google.android.gms.maps.internal.av.a(SourceFile:82)
        at com.google.maps.api.android.lib6.d.fa.run(Unknown Source)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5221)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

我如何检索可绘制对象并不重要，尝试使用BitmapFactory.fromResources 和后来的BitmapDescritpionFactory.fromBitmap 创建位图，但结果是相同的。它只是不适用于矢量可绘制对象。也尝试了不同的向量，但似乎向量复杂性不是这里的问题。

有谁知道如何解决这个崩溃问题？

@编辑

似乎问题不在于BitmapDescriptior 本身，而在于加载返回不正确位图的VectorDrawable。但是答案中提出的解决方案仍然可以。

Answer 1

可能的解决方法：

private BitmapDescriptor getBitmapDescriptor(int id) {
    Drawable vectorDrawable = context.getDrawable(id);
    int h = ((int) Utils.convertDpToPixel(42, context));
    int w = ((int) Utils.convertDpToPixel(25, context));
    vectorDrawable.setBounds(0, 0, w, h);
    Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bm);
    vectorDrawable.draw(canvas);
    return BitmapDescriptorFactory.fromBitmap(bm);
}

Answer 2

根据the bug report（posted by vaughandroid - 谢谢！）暂时不支持使用 VectorDrawable。请参阅comment in the bug report 了解更多信息。

以下是 Google 地图团队建议的解决方法：

/**
 * Demonstrates converting a {@link Drawable} to a {@link BitmapDescriptor},
 * for use as a marker icon.
 */
private BitmapDescriptor vectorToBitmap(@DrawableRes int id, @ColorInt int color) {
    Drawable vectorDrawable = ResourcesCompat.getDrawable(getResources(), id, null);
    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());
    DrawableCompat.setTint(vectorDrawable, color);
    vectorDrawable.draw(canvas);
    return BitmapDescriptorFactory.fromBitmap(bitmap);
}

这样使用：

// Vector drawable resource as a marker icon.
    mMap.addMarker(new MarkerOptions()
            .position(ALICE_SPRINGS)
            .icon(vectorToBitmap(R.drawable.ic_android, Color.parseColor("#A4C639")))
            .title("Alice Springs"));

矢量着色是一种奖励

Answer 3

或者你可以简单地使用Android KTX

例如：

val markerBitmap = ResourcesCompat.getDrawable(resources, R.drawable.ic_marker, null)?.toBitmap()
val icon = BitmapDescriptorFactory.fromBitmap(markerBitmap)
val marker = MarkerOptions().icon(icon)

参考：.toBitmap()

Answer 4

这是另一个参考： http://qiita.com/konifar/items/aaff934edbf44e39b04a

public class ResourceUtil {

@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;
}

private static Bitmap getBitmap(VectorDrawableCompat 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;
}

public static Bitmap getBitmap(Context context, @DrawableRes int drawableResId) {
    Drawable drawable = ContextCompat.getDrawable(context, drawableResId);
    if (drawable instanceof BitmapDrawable) {
        return ((BitmapDrawable) drawable).getBitmap();
    } else if (drawable instanceof VectorDrawableCompat) {
        return getBitmap((VectorDrawableCompat) drawable);
    } else if (drawable instanceof VectorDrawable) {
        return getBitmap((VectorDrawable) drawable);
    } else {
        throw new IllegalArgumentException("Unsupported drawable type");
    }
}
}

Answer 5

VectorDrawable 到 BitmapDescriptor 无色调

private BitmapDescriptor getBitmapDescriptor(@DrawableRes int id) {
        Drawable vectorDrawable = ResourcesCompat.getDrawable(getResources(), id, null);
        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 BitmapDescriptorFactory.fromBitmap(bitmap);
    }

谢谢@lbarbosa

Answer 6

Kotlin 版本

private fun getBitmapDescriptor(context: Context, id: Int): BitmapDescriptor? {
    val vectorDrawable: Drawable?
    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
        vectorDrawable = context.getDrawable(id)
    } else {
        vectorDrawable = ContextCompat.getDrawable(context, id)
    }
    if (vectorDrawable != null) {
        val w = vectorDrawable.intrinsicWidth
        val h = vectorDrawable.intrinsicHeight

        vectorDrawable.setBounds(0, 0, w, h)
        val bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
        val canvas = Canvas(bm);
        vectorDrawable.draw(canvas);

        return BitmapDescriptorFactory.fromBitmap(bm);
    }
    return null
}

Answer 7

在 Kotlin 上也是如此

private fun getBitmapDescriptorFromVector(id: Int, context: Context): BitmapDescriptor {
    var vectorDrawable: Drawable = context.getDrawable(id)
    var h = (24 * getResources().getDisplayMetrics().density).toInt();
    var w = (24 * getResources().getDisplayMetrics().density).toInt();
    vectorDrawable.setBounds(0, 0, w, h)
    var bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888)
    var canvas = Canvas(bm)
    vectorDrawable.draw(canvas)
    return BitmapDescriptorFactory.fromBitmap(bm)
}

编辑 @CoolMind 你是完全正确的，谢谢 - 编辑

Answer 8

我认为这是最简单的解决方案，因为它将实现隐藏在 MarkerOptions 的扩展函数中：

fun MarkerOptions.icon(context: Context, @DrawableRes vectorDrawable: Int): MarkerOptions {
    this.icon(ContextCompat.getDrawable(context, vectorDrawable)?.run {
        setBounds(0, 0, intrinsicWidth, intrinsicHeight)
        val bitmap = Bitmap.createBitmap(intrinsicWidth, intrinsicHeight, Bitmap.Config.ARGB_8888)
        draw(Canvas(bitmap))
        BitmapDescriptorFactory.fromBitmap(bitmap)
    })
    return this
}

所以使用时最终的结果应该是这样的：

MarkerOptions().position(myLocation).icon(requireContext(), R.drawable.ic_my_location_map)

如果您在应用程序的不同位置有多个地图，则它特别有用，因此您无需将实现复制/粘贴到多个类。