如題瘸羡，最近業(yè)務(wù)需求字體增加描邊漩仙。興高采烈的從網(wǎng)上copy下來demo運(yùn)行之后發(fā)現(xiàn)在TextView完成onMeasure之后setText出來顯示的問題就不帶描邊效果了，是代碼出現(xiàn)問題了嘛犹赖？還是我copy錯(cuò)了队他？

分析了一波源碼發(fā)現(xiàn)，網(wǎng)上常見的demo都只考慮了界面初始化階段峻村。也就是你如果在xml文件中或者在TextView繪制成功之前設(shè)置了文本麸折，則渲染正常，但一旦如果文案發(fā)生變化粘昨，想再去更改時(shí)垢啼，發(fā)現(xiàn)描邊效果不見了窜锯。

怎么解決？
思路：只要文字變化的時(shí)候芭析，重新執(zhí)行onMeasure里的邏輯不就好了锚扎？

行動：
然后我簡單扒了下TextView的源碼，發(fā)現(xiàn)每次setText之后都會觸發(fā)

    @Override
    protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) {
        super.onTextChanged(text, start, lengthBefore, lengthAfter);
        if (mTextHelper != null && !PLATFORM_SUPPORTS_AUTOSIZE && mTextHelper.isAutoSizeEnabled()) {
            mTextHelper.autoSizeText();
        }
    }

解決：
不賣關(guān)子了馁启，曬源碼吧

/**
 * Title：帶描邊的TextView
 * Describe：
 * Remark：與網(wǎng)上常見的不同驾孔，我重寫了 {@link #onTextChanged(CharSequence, int, int, int)}，這樣就支持動態(tài)修改了
 * <p>
 * Created by milo
 * E-Mail : 303767416@qq.com
 * 2020/7/16
 */
public class StrokeTextView extends AppCompatTextView {
    private static final String TAG = "StrokeTextView";

    private TextView borderText = null;///用于描邊的TextView

    private int mStrokeWidth = 3;
    private int mStrokeColor = R.color.module_magic_border_text;

    public StrokeTextView(Context context) {
        super(context);
        borderText = new TextView(context);
        init();
    }

    public StrokeTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        borderText = new TextView(context, attrs);
        init();
    }

    public StrokeTextView(Context context, AttributeSet attrs,
                          int defStyle) {
        super(context, attrs, defStyle);
        borderText = new TextView(context, attrs, defStyle);
        init();
    }

    @Override
    public void setLayoutParams(ViewGroup.LayoutParams params) {
        super.setLayoutParams(params);
        borderText.setLayoutParams(params);
    }

    @Override
    protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) {
        super.onTextChanged(text, start, lengthBefore, lengthAfter);

        if (borderText != null) {
            FZLogger.d(TAG, "onTextChanged .. borderText == " + borderText.getText().toString() + ", text == " + text.toString());
            CharSequence borderChar = borderText.getText();
            //兩個(gè)TextView上的文字必須一致
            if (borderChar == null || !borderChar.equals(this.getText())) {
                borderText.setText(getText());
                this.postInvalidate();
            }
        }
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        CharSequence borderChar = borderText.getText();

        //兩個(gè)TextView上的文字必須一致
        if (borderChar == null || !borderChar.equals(this.getText())) {
            borderText.setText(getText());
            this.postInvalidate();
        }

        borderText.measure(widthMeasureSpec, heightMeasureSpec);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        borderText.layout(left, top, right, bottom);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        borderText.draw(canvas);
        super.onDraw(canvas);
    }

    public void init() {
        TextPaint tp1 = borderText.getPaint();
        tp1.setStrokeWidth(mStrokeWidth);                                //設(shè)置描邊寬度
        tp1.setStyle(Paint.Style.STROKE);                                //對文字只描邊
        borderText.setTextColor(getResources().getColor(mStrokeColor));  //設(shè)置描邊顏色
        borderText.setGravity(getGravity());
    }

    private void setStrokeWidth(int strokeWidth) {
        this.mStrokeWidth = strokeWidth;
        init();
        invalidate();
    }

    private void setStrokeColor(@ColorRes int strokeColor) {
        this.mStrokeColor = strokeColor;
        init();
        invalidate();
    }

}

再到代碼中嘗試一下惯疙，是不是任意時(shí)刻調(diào)用 setText 都可以正確顯示描邊了呢翠勉。