自定义android方形textview文本不居中

Question

我正在尝试创建一个总是平方的textview,所以我已经实现了这个自定义类.

public class SquareTextView extends TextView {

    public SquareTextView(Context context) {
        super(context);
    }

    public SquareTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int max = Math.max(getMeasuredWidth(), getMeasuredHeight());
        setMeasuredDimension(max, max);
    }

}

这是一个示例布局,说明了问题:

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="8dp"
    android:paddingLeft="16dp"
    android:paddingRight="16dp"
    android:paddingTop="8dp">


    <com.mypackage.SquareTextView
        android:layout_width="wrap_content"
        android:layout_height="50dp"
        android:layout_gravity="right|top"
        android:background="#000"
        android:gravity="center"
        android:padding="4dp"
        android:text="1"
        android:textColor="#FFF"/>

</LinearLayout>

这是一张图片

这对于使视图平方很有效,然而,似乎重力变得混乱了.有了这个,文本似​​乎总是在左上角.如何才能使TextView始终保持平方但仍保持重力或至少能够使文本居中？

编辑:经过一些测试,我注意到如果你将宽度或高度设置为特定的dp大小,重力似乎再次起作用.所以它可能与WRAP_CONTENT属性有关.是否会在onmeasure方法中以另一种方式处理,这可能导致我自己的方法无法按预期工作？

Answer 1

希望你现在已经得到了答案.如果没有,你可以使用这个:

public class TextAlphaSquareTextView extends AppCompatTextView {
    private int mTextAlpha = 0;
    private boolean isSquare = false;

    public TextAlphaSquareTextView(Context context) {
        super(context);
        init(null);
    }

    public TextAlphaSquareTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(attrs);
    }

    public TextAlphaSquareTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(attrs);
    }

    private void init(AttributeSet attrs) {
        if (attrs == null) {

        } else {
            TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.TextAlphaSquareTextView);
            mTextAlpha = a.getInteger(R.styleable.TextAlphaSquareTextView_textAlpha, 100);
            isSquare = a.getBoolean(R.styleable.TextAlphaSquareTextView_squareMode, false);
            a.recycle();

            if(mTextAlpha < 0 || mTextAlpha > 100)
                throw new IllegalArgumentException("Alpha range should be b/w 0 to 100 (in percentage)");
            else {
                setAlphaOnTextColor();
            }
        }
        setText(getText());
    }


    void setAlphaOnTextColor() {
        int alpha = ((255 * mTextAlpha) / 100);
        setTextColor(getTextColors().withAlpha(alpha));
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        if (isSquare) {
            int width = this.getMeasuredWidth();
            int height = this.getMeasuredHeight();
            int size = Math.max(width, height);
            int widthSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
            int heightSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
            super.onMeasure(widthSpec, heightSpec);
        }
    }
}

你需要再次使用EXACT规范和计算出的大小调用super.onMeasure(),因为setMeasureDimension()似乎忽略了引力.