彻底解决 Canvas 引起的 java.lang.unsupported operation exception, android.view.GLES20Canvas.clipPath(GLES20

<applicationandroid:label="@string/application_name"android:hardwareAccelerated="false">

<applicationandroid:hardwareAccelerated="true" ...>

<application android:hardwareAccelerated="true"><activity ... /><activity android:hardwareAccelerated="false" />
</application>

    getWindow().setFlags(WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED,WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED);

myView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);

View.isHardwareAccelerated() ;//returns true if the View is attached to a hardware accelerated window.
Canvas.isHardwareAccelerated();// returns true if the Canvas is hardware accelerated

• Canvas
  • clipPath()
  • clipRegion()
  • drawPicture()
  • drawTextOnPath()
  • drawVertices()
• Paint
  • setLinearText()
  • setMaskFilter()
  • setRasterizer()
• Xfermodes
  • AvoidXfermode
  • PixelXorXfermode

In addition, some operations behave differently with hardware acceleration enabled:

• Canvas
  • clipRect(): XOR, Difference and ReverseDifference clip modes are ignored. 3D transforms do not apply to the clip rectangle
  • drawBitmapMesh(): colors array is ignored
• Paint
  • setDither(): ignored
  • setFilterBitmap(): filtering is always on
  • setShadowLayer(): works with text only

• PorterDuffXfermode
  • PorterDuff.Mode.DARKEN will be equivalent to SRC_OVER when blending against the framebuffer.
  • PorterDuff.Mode.LIGHTEN will be equivalent to SRC_OVER when blending against the framebuffer.
  • PorterDuff.Mode.OVERLAY will be equivalent to SRC_OVER when blending against the framebuffer.
• ComposeShader
  • ComposeShader can only contain shaders of different types (a BitmapShader and a LinearGradient for instance, but not two instances of BitmapShader )
  • ComposeShader cannot contain a ComposeShader