Android开发实现在TextView前面加标签示例

目录

• 效果
• 代码实现： 自定义TextView
• 自定义一个layout_texttab布局
• 使用

效果

代码实现： 自定义TextView

public class TagTextView extends AppCompatTextView {
    private View view;//标签布局的最外层布局
    private Context mContext;
    private TextView tv_tag;
    private StringBuffer content_buffer;
    //必须重写所有的构造器，否则可能会出现无法inflate布局的错误！
    public TagTextView(Context context) {
        super(context);
        mContext = context;
    }
    public TagTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mContext = context;
    }
    public TagTextView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mContext = context;
    }
    public void setContentAndTag(String content, List<String> tags) {
        content_buffer = new StringBuffer();
        for (String item : tags) {//将每个tag的内容添加到content后边，之后将用drawable替代这些tag所占的位置
            content_buffer.append(item);
        }
        content_buffer.append(content);
        SpannableString spannableString = new SpannableString(content_buffer);
        for (int i = 0; i < tags.size(); i++) {
            String item = tags.get(i);
            View view = LayoutInflater.from(mContext).inflate(R.layout.layout_texttab, null);//R.layout.tag是每个标签的布局
            tv_tag = view.findViewById(R.id.tv_tag);
            tv_tag.setText(item);
            Bitmap bitmap = convertViewToBitmap(view);
            Drawable d = new BitmapDrawable(bitmap);
            d.setBounds(0, 0, tv_tag.getWidth(), tv_tag.getHeight());//缺少这句的话，不会报错，但是图片不回显示
            ImageSpan span = new ImageSpan(d, ImageSpan.ALIGN_BOTTOM);//图片将对齐底部边线
            int startIndex;
            int endIndex;
            startIndex = getLastLength(tags, i );
            endIndex = startIndex + item.length();
            Log.e("tag", "the start is" + startIndex + "the end is" + endIndex);
            spannableString.setSpan(span, startIndex, endIndex, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
        }
        setText(spannableString);
        setGravity(Gravity.CENTER_VERTICAL);
    }
    private static Bitmap convertViewToBitmap(View view) {
        view.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED), View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
        view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
        view.buildDrawingCache();
        Bitmap bitmap = view.getDrawingCache();
        return bitmap;
    }
    private int getLastLength(List<String> list, int maxLength) {
        int length = 0;
        for (int i = 0; i < maxLength; i++) {
            length += list.get(i).length();
        }
        return length;
    }
}

自定义一个layout_texttab布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    <TextView
        android:id="@+id/tv_tag"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:layout_marginBottom="2dp"
        android:layout_marginRight="5dp"
        android:background="@drawable/round_blue"
        android:gravity="center_vertical"
        android:paddingBottom="2dp"
        android:paddingLeft="3dp"
        android:paddingRight="3dp"
        android:text="标签"
        android:textColor="@android:color/white"
        android:textSize="12sp"/>
</LinearLayout>

使用

<com.zc.tool.TagTextView
        android:id="@+id/text_tab"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="12dp"
        android:textColor="@color/white"
        android:gravity="center" />

 List<String> tags = new ArrayList<>();
        tags.add("@用户");
        tags.add("@程序猿");
        tags.add("@产品经理");
        textTab.setContentAndTag("改个需求", tags);