在渲染到布局之前获取文本视图的高度 [英] Getting height of text view before rendering to layout

问题描述

找不到任何好的解决方案计算 textview 高度其中设置了文本 在渲染之前 textview 到布局.请帮忙

Could not find any good solution calculating textview height where text was set before rendering textview to layout. Any help please

推荐答案

2个解决方案

最初使用解决方案 1，后来找到解决方案 2.两者都有效，这确实是您喜欢的.

2 solutions

Used solution 1 at first and found solution 2 later on. Both work, it's really what you prefer.

重要的是确保所有尺寸都正确，因为在 sp 或 px 中混合字体大小会产生很大差异，具体取决于您在哪个屏幕上进行测试.

Important is to make sure you got all the dimensions right since mixing font sizes in sp or px will give quite a difference depending on what screen you test on.

一个非常基本的示例项目可在 https://github.com/hanscappelle/SO-3654321

A very basic example project is available at https://github.com/hanscappelle/SO-3654321

原始问题的主要问题是下面方法中的 TextView 应该配置为我们的 TextView 应该呈现到布局.我认为这个解决方案对许多面临这个问题的人来说很有价值.

Main issue with original question is TextView in below method should be configured as our TextView which should be rendered to layout. I think this solution is valuable for many people who faced this problem.

public static int getHeight(Context context, CharSequence text, int textSize, int deviceWidth, Typeface typeface,int padding) {
            TextView textView = new TextView(context);
            textView.setPadding(padding,0,padding,padding);
            textView.setTypeface(typeface);
            textView.setText(text, TextView.BufferType.SPANNABLE);
            textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, textSize);
            int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(deviceWidth, View.MeasureSpec.AT_MOST);
            int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
            textView.measure(widthMeasureSpec, heightMeasureSpec);
            return textView.getMeasuredHeight();
        }

以及如何使用它的示例:

And an example of how to use this:

// retrieve deviceWidth
int deviceWidth;
WindowManager wm = (WindowManager) textView.getContext().getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2){
    Point size = new Point();
    display.getSize(size);
    deviceWidth = size.x;
} else {
    deviceWidth = display.getWidth();
}
// the text to check for
String exampleTextToMeasure = "some example text that will be long enough to make this example split over multiple lines so we can't easily predict the final height";
//  some dimensions from dimes resources to take into account
int textSize = getContext().getResources().getDimensionPixelSize(R.dimen.text_size);
int padding = getContext().getResources().getDimensionPixelSize(R.dimen.text_padding);

// final calculation of textView height
int measuredTextHeight = getHeight(getContext(), exampleTextToMeasure, textSize, deviceWidth, TypeFace.DEFAULT, padding); 

使用 TextPaint 和 StaticLayout 的解决方案 2

此方法依赖于 TextPaint 和 StaticLayout，这也为我迄今为止测试过的所有 API 级别提供了可靠的结果.注意尺寸单位；一切都应该以像素为单位！

Solution 2 using TextPaint and StaticLayout

This method relies on a TextPaint and StaticLayout which also gives reliable results on all API levels I've tested so far. Pay good attention to units of dimensions; all should be in pixels!

来源:测量要在画布上绘制的文本高度(安卓)

    public static int method1UsingTextPaintAndStaticLayout(
            final CharSequence text,
            final int textSize, // in pixels
            final int deviceWidth, // in pixels
            final int padding // in pixels
    ) {

        TextPaint myTextPaint = new TextPaint();
        myTextPaint.setAntiAlias(true);
        // this is how you would convert sp to pixels based on screen density
        //myTextPaint.setTextSize(16 * context.getResources().getDisplayMetrics().density);
        myTextPaint.setTextSize(textSize);
        Layout.Alignment alignment = Layout.Alignment.ALIGN_NORMAL;
        float spacingMultiplier = 1;
        float spacingAddition = padding; // optionally apply padding here
        boolean includePadding = padding != 0;
        StaticLayout myStaticLayout = new StaticLayout(text, myTextPaint, deviceWidth, alignment, spacingMultiplier, spacingAddition, includePadding);
        return myStaticLayout.getHeight();
    }

这篇关于在渲染到布局之前获取文本视图的高度的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！