自动调整TextView以在画布上绘制

Question

我试着在上面显示一些文字PDF document.此文本可能很长或很短,但应该在一行上.这就是我选择TextViewCompat.setAutoSizeTextTypeWithDefaults实用程序方法的原因,但是在绘制时它似乎不起作用canvas.文本被裁剪而不是减少.

这是我的代码:

PageInfo startingPageInfo = new Builder(STANDARD_PDF_PAGE_WIDTH, STANDARD_PDF_PAGE_HEIGHT, 1).create();
final Page startingPage = document.startPage(startingPageInfo);

Canvas canvas = startingPage.getCanvas();
canvas.save();

final TextView documentTitle = new TextView(this);
TextViewCompat.setAutoSizeTextTypeWithDefaults(documentTitle, TextViewCompat.AUTO_SIZE_TEXT_TYPE_UNIFORM);
documentTitle.setLines(1);
documentTitle.setText(String.format("%s - %s", category.getName(), period));
documentTitle.setTextSize(TypedValue.COMPLEX_UNIT_SP, 56);
documentTitle.setTypeface(null, BOLD);
documentTitle.setTextColor(Color.BLACK);

int measuredWidth = MeasureSpec.makeMeasureSpec(canvas.getWidth() - 100, MeasureSpec.EXACTLY);
int measuredHeight = MeasureSpec.makeMeasureSpec(100, MeasureSpec.EXACTLY);
documentTitle.measure(measuredWidth, measuredHeight);
documentTitle.layout(0, 0, measuredWidth, measuredHeight); 

canvas.translate(titleDx, titleDy);
documentTitle.draw(canvas);

我对Android内部的自定义视图感到不舒服,所以我可能在这里做错了,任何帮助都会受到赞赏.

Answer 1

重写2+

您遇到的问题是由以下行引起的：

documentTitle.layout(0, 0, measuredWidth, measuredHeight);

这行应该是：

documentTitle.layout(0, 0, width, height);

您的代码将宽度和高度设置为一些天文值，因此文本始终“适合”。

这是（大部分）您的代码工作的简短演示。我使用了一个习惯LinearLayout，但这并不重要。我认为上面的更改本身就应该起作用，但我可能做了一些其他的小调整，您可能会在下面的代码中找到这些调整。

MyLinearLayout.java

public class MyLinearLayout extends LinearLayout {
    private AppCompatTextView documentTitle;

    public MyLinearLayout(@NonNull Context context) {
        super(context);
        init();
    }

    public MyLinearLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public MyLinearLayout(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        documentTitle = new AppCompatTextView(this.getContext());
    }

    @Override
    public void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        String displayString = String.format("%s - %s", "Some very, very, ", "very, very long text");

        int width = getWidth() - getPaddingEnd();
        int height = 100;

        ViewGroup.LayoutParams lp = new ViewGroup.LayoutParams(width, height);
        documentTitle.setLayoutParams(lp);

        TextViewCompat.setAutoSizeTextTypeWithDefaults(documentTitle, TextViewCompat.AUTO_SIZE_TEXT_TYPE_UNIFORM);
        documentTitle.setTextSize(TypedValue.COMPLEX_UNIT_SP, 56);
        documentTitle.setTypeface(null, BOLD);
        documentTitle.setTextColor(Color.BLACK);
        documentTitle.setMaxLines(1);

        int measuredWidth = MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY);
        int measuredHeight = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
        documentTitle.measure(measuredWidth, measuredHeight);
        // Arguments here are width and height, not measureWidth and measeredHeight.
        documentTitle.layout(0, 0, width, height);

        canvas.save();
        for (int i = 0; i < 5; i++) {
            documentTitle.setText(displayString);
            documentTitle.draw(canvas);
            displayString += " - longer - longer";
            canvas.translate(0, 150);
        }
        canvas.restore();
    }

}