Struct Canvas

pub struct Canvas { /* private fields */ }

Canvas 类包含“绘制”调用。要绘制某些内容，您需要 4 个基本组件：用于保存像素的 Bitmap、用于托管绘制调用（写入位图）的 Canvas、绘图基元（例如 Rect、Path、文本、Bitmap）和 Paint（用于描述绘图的颜色和样式）。

开发者指南 有关如何使用 Canvas 的更多信息，请阅读 Canvas 和 Drawables 开发者指南。

Methods from Deref<Target = GlobalRef>

pub fn as_obj(&self) -> &JObject<'static>

Get the object from the global ref

This borrows the ref and prevents it from being dropped as long as the JObject sticks around.

Methods from Deref<Target = JObject<'static>>

pub fn as_raw(&self) -> *mut _jobject

Returns the raw JNI pointer.

Trait Implementations

impl Debug for Canvas

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Deref for Canvas

type Target = GlobalRef

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl From<&GlobalRef> for Canvas

fn from(obj: &GlobalRef) -> Self

Converts to this type from the input type.

impl Into<GlobalRef> for &Canvas

fn into(self) -> GlobalRef

Converts this type into the (usually inferred) input type.

impl JObjNew for Canvas

type Fields = ()

字段类型

fn _new(this: &GlobalRef, fields: Self::Fields) -> Self

从java对象创建本地对象。 this java对象引用。

fn null() -> Self

where Self: Sized, Self::Fields: Default,

创建空对象。

impl JObjRef for Canvas

fn java_ref(&self) -> GlobalRef

获取java对象引用。

impl JType for Canvas

const CLASS: &'static str = "android/graphics/Canvas"

java类的名称。

const OBJECT_SIG: &'static str = "Landroid/graphics/Canvas;"

对象的签名描述。

type Error = Error

错误类型。

const DIM: u8 = 0u8

数组维度，0表示不是数组

impl PartialEq for Canvas

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl ToString for Canvas

fn to_string(&self) -> String

Converts the given value to a String.