android - 如何在 TextView 上应用图像和文本跨度

Question

我想在 TextView 的文本上应用 span 有两个目的。首先是解析笑脸，其次是突出显示文本。我出于同样的目的创建了这个方法，但没有用。请告诉我哪里出错了。

public CharSequence addSmileySpansTextFilter(final CharSequence text,String filter,int color) {
    SpannableStringBuilder builder = new SpannableStringBuilder(text);

    Matcher matcher = mPattern.matcher(text);
    while (matcher.find()) {
        int resId = mSmileyToRes.get(matcher.group());
        builder.setSpan(new ImageSpan(mContext, resId), matcher.start(), matcher.end(),
                Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);


    }

        if (filter!=null&&!filter.equals("")) {

            int startPos = builder.toString().toLowerCase(Locale.US).indexOf(filter.toLowerCase(Locale.US));
            int endPos = startPos + filter.length();


            if (startPos != -1) // This should always be true, just a sanity check
            {

                BackgroundColorSpan highlightSpan = new BackgroundColorSpan(color);

                builder.setSpan(highlightSpan, startPos, endPos,Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

            }
        }
    return builder;
}

Answer 1

试试这个 .. TextViewWithImages 的 Utils 类

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import android.content.Context;
import android.text.Spannable;
import android.text.style.ImageSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.TextView;

public class TextViewWithImages extends TextView {

    public TextViewWithImages(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    public TextViewWithImages(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public TextViewWithImages(Context context) {
        super(context);
    }
    @Override
    public void setText(CharSequence text, BufferType type) {
        Spannable s = getTextWithImages(getContext(), text);
        super.setText(s, BufferType.SPANNABLE);
    }

    private static final Spannable.Factory spannableFactory = Spannable.Factory.getInstance();

    private static boolean addImages(Context context, Spannable spannable) {
        Pattern refImg = Pattern.compile("\\Q[img src=\\E([a-zA-Z0-9_]+?)\\Q/]\\E");
        boolean hasChanges = false;

        Matcher matcher = refImg.matcher(spannable);
    while (matcher.find()) {
        boolean set = true;
        for (ImageSpan span : spannable.getSpans(matcher.start(), matcher.end(), ImageSpan.class)) {
            if (spannable.getSpanStart(span) >= matcher.start()
             && spannable.getSpanEnd(span) <= matcher.end()
               ) {
                spannable.removeSpan(span);
            } else {
                set = false;
                break;
            }
        }
        String resname = spannable.subSequence(matcher.start(1), matcher.end(1)).toString().trim();
        int id = context.getResources().getIdentifier(resname, "drawable", context.getPackageName());
        if (set) {
            hasChanges = true;
            spannable.setSpan(  new ImageSpan(context, id),
                                matcher.start(),
                                matcher.end(),
                                Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
                             );
        }
    }

        return hasChanges;
    }
    private static Spannable getTextWithImages(Context context, CharSequence text) {
        Spannable spannable = spannableFactory.newSpannable(text);
        addImages(context, spannable);
        return spannable;
    }
}

使用:

在 res/layout/mylayout.xml 中:

<com.xyz.customandroid.TextViewWithImages
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textColor="#FFFFFF00"
                android:text=""
                android:textSize="12dip"
                style=...
                />

请注意，如果您将 TextViewWithImages.java 放在 com/xyz/customandroid/以外的某个位置，您还必须更改包名称，上面的 com.xyz.customandroid。