Android自定义控件：具有描边效果的TextView

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public class StrokeTextView extends TextView {

	TextPaint m_TextPaint;
	int mInnerColor;
	int mOuterColor;
	
	public StrokeTextView(Context context,int outerColor,int innnerColor) {
		super(context);
		m_TextPaint = this.getPaint();
		this.mInnerColor = innnerColor;
		this.mOuterColor = outerColor;
		
		// TODO Auto-generated constructor stub
	}

	public StrokeTextView(Context context, AttributeSet attrs) {
		super(context, attrs);
		m_TextPaint = this.getPaint();
		//获取自定义的XML属性名称
		TypedArray a = context.obtainStyledAttributes(attrs,R.styleable.StrokeTextView);
		//获取对应的属性值
		this.mInnerColor = a.getColor(R.styleable.StrokeTextView_innnerColor,0xffffff);
		this.mOuterColor = a.getColor(R.styleable.StrokeTextView_outerColor,0xffffff);
		
	}

	public StrokeTextView(Context context, AttributeSet attrs, int defStyle,int outerColor,int innnerColor) {
		super(context, attrs, defStyle);
		m_TextPaint = this.getPaint();
		this.mInnerColor = innnerColor;
		this.mOuterColor = outerColor;
		// TODO Auto-generated constructor stub
	}

	private boolean m_bDrawSideLine = true; // 默认采用描边

	/**
	 * 
	 */
	@Override
	protected void onDraw(Canvas canvas) {
		if (m_bDrawSideLine) {
			// 描外层
			// super.setTextColor(Color.BLUE); // 不能直接这么设，如此会导致递归
			setTextColorUseReflection(mOuterColor);
			m_TextPaint.setStrokeWidth(5); // 描边宽度
			m_TextPaint.setStyle(Style.FILL_AND_STROKE); // 描边种类
			m_TextPaint.setFakeBoldText(true); // 外层text采用粗体
			m_TextPaint.setShadowLayer(1, 0, 0, 0); // 字体的阴影效果，可以忽略
			super.onDraw(canvas);

			// 描内层，恢复原先的画笔

			// super.setTextColor(Color.BLUE); // 不能直接这么设，如此会导致递归
			setTextColorUseReflection(mInnerColor);
			m_TextPaint.setStrokeWidth(0);
			m_TextPaint.setStyle(Style.FILL_AND_STROKE);
			m_TextPaint.setFakeBoldText(false);
			m_TextPaint.setShadowLayer(0, 0, 0, 0);
			
		}
		super.onDraw(canvas);
	}

	/**
	 * 使用反射的方法进行字体颜色的设置
	 * @param color
	 */
	private void setTextColorUseReflection(int color) {
		Field textColorField;
		try {
			textColorField = TextView.class.getDeclaredField("mCurTextColor");
			textColorField.setAccessible(true);
			textColorField.set(this, color);
			textColorField.setAccessible(false);
		} catch (NoSuchFieldException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		}
		m_TextPaint.setColor(color);
	}

}

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<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- 自定义控件的名称 -->
    <declare-styleable name="StrokeTextView">
        <!-- 自定义的属性名称 和对应的单位 -->
        <attr name="outerColor" format="color|reference" />
        <attr name="innnerColor" format="color|reference" />
    </declare-styleable>
</resources>

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<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >

    <com.example.demo.StrokeTextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" 
        android:textSize="28sp"
        app:outerColor="#000000"
        app:innnerColor="#ffffff"
        android:layout_centerInParent="true"/>

</RelativeLayout>