Android - 从带有 html 数据的 textview 获取文本位置

Question

我已将 html 数据设置为我的 textview。当我从 textview 中选择任何单词/字符时，我想将该单词加粗并用新的替换原始 html 数据。

String html = "<p>hello this is android testing</p>";

像这样我的 html 中可能有很多 html 标签。如果我想让“android”字加粗，如何用“android”替换原始html字符串。

我想要<p>hello this is <strong>android</strong> testing</p> 作为结果。

Answer 1

使用 SelectableTextView 获取选中的文本。你可以在 github here 上看到这个实现。

检查答案here。这可能对你有帮助

你可以使用标签加粗，

 String string= "<b>" + android + "</b> " + remainingString;   

 textView.setText(Html.fromHtml(string));

Answer 2

您可以先将字符串内容设置到TextView，然后使用setCustomSelectionActionModeCallback(...) 截取TextView 中的选择。

在下面的示例中，所选单词将被 <strong>...</strong> 包围。

例如选择“测试”将使以下字符串在 TextView 中可见。

你好，这是 android testing android bla bla android bla bla android bla

然后在已转换的 TextView 内容中选择“android”上的最后一个实例将使以下字符串在 TextVIew 中可见。

你好这是android测试android bla bla android bla bla android bla

代码：

public class MainActivity extends AppCompatActivity {

    String yourString = "<p>hello this is android testing android bla bla android bla bla android bla</p>";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView tv = (TextView)findViewById(R.id.opening_today);
        tv.setText(Html.fromHtml(yourString));
        tv.setCustomSelectionActionModeCallback(new CallbackListener(tv));
    }

    class CallbackListener implements ActionMode.Callback{

        private TextView tv;
        private String strongS = "<strong>";
        private String strongE = "</strong>";

        public CallbackListener(TextView tv) {
            this.tv = tv;
        }

        @Override
        public boolean onCreateActionMode(ActionMode mode, Menu menu) {
            int start = tv.getSelectionStart();
            int end = tv.getSelectionEnd();

            if( start == 0 && end == 0)
                return false;

            String content = tv.getText().toString();
            String token = content.substring(start, end);
            String before = content.substring(0, start);
            String after = content.substring(end, content.length());
            content = makeItStrong(before, after, token);
            tv.setText(Html.fromHtml(content));
            return false;
        }

        private String makeItStrong(String before, String after, String token){
            return cleanTags(before, strongS, strongE) + strongS + token + strongE + cleanTags(after, strongS, strongE);
        }

        private String cleanTags(String source, String... exp){
            for(String s: exp){
                source = source.replace(s, "");
            }
            return source;
        }

        @Override
        public boolean onActionItemClicked(ActionMode mode, MenuItem item) { return true; }

        @Override
        public boolean onPrepareActionMode(ActionMode mode, Menu menu) { return false; }

        @Override
        public void onDestroyActionMode(ActionMode mode) {}
    }
}

Answer 3

使用下面的代码，可以多次高亮格式化文本，每次都可以得到所有高亮的累加结果。

int getOccuranceNumber(String text ,String selection, int selectionStartIndex){
    int index = text.indexOf(selection);
    int occuranceNumber = 0;
    while (index >= 0) {
        if(index == selectionStartIndex){
            return occuranceNumber;
        }else {
            index = text.indexOf(selection, index + 1);
            occuranceNumber++;
        }
    }
    return occuranceNumber;
}
int getOccuranceIndex(String text ,String selection, int occuranceNumber){
    int index = text.indexOf(selection);
    int i = 0;
    while (i!=occuranceNumber) {

            index = text.indexOf(selection, index + 1);
            i++;

    }
    return index;
}
public String toHex(String arg) {
    TextView textV = new TextView(context);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        textV.setText(Html.fromHtml(arg,Html.FROM_HTML_MODE_LEGACY));
    }else{
        textV.setText(Html.fromHtml(arg));
    }
    String textFormated ="";
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        textFormated =  Html.toHtml((Spanned) textV.getText(),TO_HTML_PARAGRAPH_LINES_CONSECUTIVE).toString();
    }else{
        textFormated =  Html.toHtml((Spanned) textV.getText()).toString();
    }
    return textFormated.replace("<p dir=\"rtl\">","").replace("</p>","").replace("\n","");
}
public void highLightText(TextView textView){
    String textFormated ="";
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        textFormated =  Html.toHtml((Spanned) textView.getText(),TO_HTML_PARAGRAPH_LINES_CONSECUTIVE).toString();
    }else{
        textFormated =  Html.toHtml((Spanned) textView.getText()).toString();
    }

    String text = textView.getText().toString();
    String selection = text.substring(textView.getSelectionStart(),textView.getSelectionEnd());
    int occuranceNum = getOccuranceNumber(text,selection,textView.getSelectionStart());
    String selectionHex = toHex(selection);

    int formatedTextSelectionStart = getOccuranceIndex(textFormated,selectionHex,occuranceNum);
    if(formatedTextSelectionStart<0)return;
    int formatedTextSelectionEnd = formatedTextSelectionStart + selectionHex.length();
    String formatedTextPart1 = textFormated.substring(0,formatedTextSelectionStart);
    String formatedTextPart2 = textFormated.substring(formatedTextSelectionStart,formatedTextSelectionEnd);
    String formatedTextPart3 = textFormated.substring(formatedTextSelectionEnd,textFormated.length());
    String colorOpenTag="<font color=\"#f7c627\">";
    String colorCloseTag="</font>";
    String finalText = formatedTextPart1+colorOpenTag+formatedTextPart2+colorCloseTag+formatedTextPart3;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        textView.setText(Html.fromHtml(finalText,Html.FROM_HTML_MODE_LEGACY));
    }else{
        textView.setText(Html.fromHtml(finalText));
    }
}