解決EditText游標定位問題

需求：

有時候我們的需求是讓輸入從右邊開始，如下圖，這是產品和ux需要的

在正常的通過xml佈局後，在有的機型上可能顯示為：| Hometown

有些是設定屬性的方式來修改這個bug，但是比較穩妥的是自己定義一個EditText，自己畫一個Cursor

如下程式碼，直接copy進專案可直接使用：

public class CursorEditText extends AppCompatEditText {

    private CharSequence mHint;
    private Paint mPaint;
    private int mHintTextColor;

    public CursorEditText(Context context) {
        this(context, null);
    }

    public CursorEditText(Context context, AttributeSet attrs) {
        this(context, attrs, android.support.v7.appcompat.R.attr.editTextStyle);
    }

    public CursorEditText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs, defStyleAttr);
    }

    private void init(Context context, AttributeSet attrs, int defStyleAttr) {
        mHint = getHint();
        setHint("");
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.DITHER_FLAG);
        mPaint.setTextSize(getTextSize());
        mPaint.setTextAlign(Paint.Align.RIGHT);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (TextUtils.isEmpty(mHint) || !TextUtils.isEmpty(getText())) {
            return;
        }
        canvas.save();
        ColorStateList hintTextColors = getHintTextColors();
        if (hintTextColors != null) {
            int color = hintTextColors.getColorForState(getDrawableState(), 0);
            if (color != mHintTextColor) {
                mHintTextColor = color;
                mPaint.setColor(color);
            }
        }

        Paint.FontMetricsInt fontMetrics = mPaint.getFontMetricsInt();
        int baseline = (getHeight() - fontMetrics.bottom + fontMetrics.top) / 2 - fontMetrics.top;
        canvas.drawText(mHint, 0, mHint.length(),
                getWidth() - getPaddingRight() + getScrollX(),
                baseline, mPaint);
        canvas.restore();
    }
}