便捷方式

Question

我有一个随机背景颜色的TextView（可能是任何颜色）。我在Textview上也有一个需要可读的文本。我认为最好的解决方案是以白色突出显示所述文本并将文本颜色设置为黑色。

我的问题是：是否可以从XML中突出显示texview中的文本？

我的布局中有以下内容：

  <TextView
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:id="@+id/colorButton4"
        android:layout_gravity="right|bottom"
        android:background="@drawable/layout_border"
        android:layout_marginRight="30dp"
        android:layout_marginBottom ="30dp"
        android:clickable="true"
        android:onClick="onClick"
        android:gravity="center"
        android:textColorHighlight="@color/bgWhite"
        android:textColor="@color/Black"
        android:text="5431354" />

但它并没有强调文本。

Answer 1

您可能希望为此使用SpannableString，这允许在TextView中以不同方式呈现字符串的各个部分。

像这样：

    SpannableString str = new SpannableString("Highlighted. Not highlighted.");
    str.setSpan(new BackgroundColorSpan(Color.YELLOW), 0, 11, 0);
    textView.setText(str);

Answer 2

要突出显示所有特定文本，请使用此方法：

private void highlightString(String input) {
//Get the text from text view and create a spannable string
SpannableString spannableString = new SpannableString(mTextView.getText());
//Get the previous spans and remove them
BackgroundColorSpan[] backgroundSpans = spannableString.getSpans(0, spannableString.length(), BackgroundColorSpan.class);

for (BackgroundColorSpan span: backgroundSpans) {
    spannableString.removeSpan(span);
}

//Search for all occurrences of the keyword in the string
int indexOfKeyword = spannableString.toString().indexOf(input);

while (indexOfKeyword > 0) {
    //Create a background color span on the keyword
    spannableString.setSpan(new BackgroundColorSpan(Color.YELLOW), indexOfKeyword, indexOfKeyword + input.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);

    //Get the next index of the keyword
    indexOfKeyword = spannableString.toString().indexOf(input, indexOfKeyword + input.length());
}

//Set the final text on TextView
mTextView.setText(spannableString);}

注意：mTextView是一个TextView对象，您要在其中突出显示文本

Answer 3

我编写了Kotlin方法，该方法将突出显示String中所有出现的所有关键字，并返回SpannableString。

fun main() {
    textView.text = highlightKeywords(
        highlightColor = ContextCompat.getColor(context, R.color.colorAccent),
        message = "Hello World, and Hello to all my Hello Friends.",
        keywords = listOf("Hello")
    )
}


fun highlightKeywords(
    highlightColor: Int,
    message: String,
    keywords: List<String>,
): SpannableString {
    val spannableString = SpannableString(message)
    keywords.forEach { keyword ->
        if (!keyword.isBlank()) {
            var startIndex = message.indexOf(keyword)

            while (startIndex >= 0) {
                spannableString.setSpan(
                    ForegroundColorSpan(highlightColor),
                    startIndex,
                    startIndex + keyword.length,
                    Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
                )

                startIndex = message.indexOf(keyword, startIndex + keyword.length)
            }
        }
    }
    return spannableString
}

Answer 4

Suraj's answer 很棒并且有效，但缺少 2 个组件。首先，它不会突出显示第一个单词（如 Rany 评论的那样），其次，它不会忽略大小写，因此在此字符串中搜索 "test"："This is a Test" 将找不到任何内容。

这是我更新的答案，它通过传递的参数解决了这两个问题，并且还添加了 alpha，以防您想使用自定义颜色进行突出显示。请注意，重载的第一个方法是如何返回前一个方法所做的操作而不是选择的第一个项目的示例。

    
    /**
     * Use this method to get the same return as the previous method
     */
    public static SpannableString buildHighlightString(String originalText, String textToHighlight){
        return buildHighlightString(originalText, textToHighlight, false, Color.YELLOW, 1.0F);
    }
    
    /**
     * Build a spannable String for use in highlighting text colors
     * 
     * @param originalText The original text that is being highlighted
     * @param textToHighlight The text / query that determines what to highlight
     * @param ignoreCase Whether or not to ignore case. If true, will ignore and "test" will have
     *                   the same return as "TEST". If false, will return an item as highlighted
     *                   only if it matches it case specficic.
     * @param highlightColor The highlight color to use. IE {@link Color#YELLOW} || {@link Color#BLUE}
     * @param colorAlpha Alpha to adjust how transparent the color is. 1.0 means it looks exactly
     *                   as it should normally where as 0.0 means it is completely transparent and
     *                   see-through. 0.5 means it is 50% transparent. Useful for darker colors
     */
    public static SpannableString buildHighlightString(String originalText, String textToHighlight,
                                                       boolean ignoreCase, @ColorInt int highlightColor,
                                                       @FloatRange(from = 0.0, to = 1.0) float colorAlpha){
        SpannableString spannableString = new SpannableString(originalText);
        if (TextUtils.isEmpty(originalText) || TextUtils.isEmpty(textToHighlight)) {
            return spannableString;
        }
        String lowercaseOriginalString = originalText.toLowerCase();
        String lowercaseTextToHighlight = textToHighlight.toLowerCase();
        if(colorAlpha < 1){
            highlightColor = ColorUtils.setAlphaComponent(highlightColor, ((int)(255*colorAlpha)));
        }
        //Get the previous spans and remove them
        BackgroundColorSpan[] backgroundSpans = spannableString.getSpans(0, spannableString.length(), BackgroundColorSpan.class);
        for (BackgroundColorSpan span: backgroundSpans) {
            spannableString.removeSpan(span);
        }
        //Search for all occurrences of the keyword in the string
        int indexOfKeyword = (ignoreCase)
                ? lowercaseOriginalString.indexOf(lowercaseTextToHighlight)
                : originalText.indexOf(textToHighlight);
        while (indexOfKeyword != -1) {
            //Create a background color span on the keyword
            spannableString.setSpan(new BackgroundColorSpan(highlightColor), indexOfKeyword,
                    indexOfKeyword + (textToHighlight.length()), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
            
            //Get the next index of the keyword
            indexOfKeyword = (ignoreCase)
                    ? lowercaseOriginalString.indexOf(lowercaseTextToHighlight, (indexOfKeyword) + textToHighlight.length())
                    : originalText.indexOf(textToHighlight, (indexOfKeyword) + textToHighlight.length());
        }
        return spannableString;
    }

Answer 5

https://github.com/datanapps/HighlightedTextView

<datanapps.highlightedtextview.HighLightTextView
    android:id="@+id/tv2"
    android:layout_below="@+id/tv1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Android is an open source and Linux-based operating system for mobile devices such as smartphones and tablet computers."
    android:textColor="@color/white"
    app:fontFamily="serif"
    android:lineSpacingExtra="50sp"
    android:layout_marginTop="20dp"
    android:textSize="20sp"
    android:textAlignment="viewEnd"
    app:highLightColor="@color/blue"
    />

Answer 6

如果你已经检查了TextView的文档，你会发现android:textColorHighlight没有做你想做的事：https://developer.android.com/reference/android/widget/TextView.html#attr_android:textColorHighlight

仅在选择文字时使用，例如在EditText中。您需要将TextView的背景设置为“高亮”它。

Answer 7

便捷方式

您可以使用Spannable类来设置文本格式。

textView.setText("Hello, I am Awesome, Most Awesome"); // set text first
setHighLightedText(textView, "a"); // highlight all `a` in TextView

输出将类似于下图。

这是方法。

 /**
     * use this method to highlight a text in TextView
     *
     * @param tv              TextView or Edittext or Button (or derived from TextView)
     * @param textToHighlight Text to highlight
     */
    public void setHighLightedText(TextView tv, String textToHighlight) {
        String tvt = tv.getText().toString();
        int ofe = tvt.indexOf(textToHighlight, 0);
        Spannable wordToSpan = new SpannableString(tv.getText());
        for (int ofs = 0; ofs < tvt.length() && ofe != -1; ofs = ofe + 1) {
            ofe = tvt.indexOf(textToHighlight, ofs);
            if (ofe == -1)
                break;
            else {
                // set color here
                wordToSpan.setSpan(new BackgroundColorSpan(0xFFFFFF00), ofe, ofe + textToHighlight.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                tv.setText(wordToSpan, TextView.BufferType.SPANNABLE);
            }
        }
    }

您可以check this answer以获得可点击的突出显示文本。

Answer 8

在Android平台上工作了4年后，我可以安全地说没有XML之外的代码是不可能的。如果您可以使用一些代码，那么其他人共享的解决方案将为您提供帮助！

突出显示textview中的文本

8 个答案:

便捷方式