android 3(API <= 11)组件中的新可选TextView

Question

经过漫长而耗时的搜索,我找不到一个可以在textview中为android API级别<= 11选择文本的组件.我写过这个可能对你有所帮助的组件:

public class SelectableTextView extends TextView {

public static int _SelectedBackgroundColor = 0xffA6D4E1;
public static int _SelectedTextColor = 0xff000000;
private OnTouchListener lastOnTouch;
protected int textOffsetStart;
protected int textOffsetEnd;
private OnLongClickListener lastOnLongClick;
protected boolean longCliked;
protected boolean isDowned;
protected int textSelectedEnd;
protected int textSelectedStart;
private static SelectableTextView lastInstance;

public SelectableTextView(Context context) {
    super(context);
}

public void setTextIsSelectable(boolean selectable) {
    // TODO:ANDROID3
    // if:androidversion>=3
    // super.setTextIsSelectable(selectable);
    // else
    super.setLongClickable(true);
    super.setOnLongClickListener(getSelectableLongClick());
    super.setOnTouchListener(getSelectableOnTouch());
}

private OnLongClickListener getSelectableLongClick() {
    return new OnLongClickListener() {

        @Override
        public boolean onLongClick(View v) {
            longCliked = true;
            if (lastOnLongClick != null) {
                lastOnLongClick.onLongClick(v);
            }
            return true;
        }
    };
}

@Override
public void setOnTouchListener(OnTouchListener l) {
    super.setOnTouchListener(l);
    this.lastOnTouch = l;
}

@Override
public void setOnLongClickListener(OnLongClickListener l) {
    super.setOnLongClickListener(l);
    this.lastOnLongClick = l;
}

private OnTouchListener getSelectableOnTouch() {
    return new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            int action = event.getAction();

            if (action == MotionEvent.ACTION_DOWN) {
                if (lastInstance == null)
                    lastInstance = SelectableTextView.this;
                if (lastInstance != null && lastInstance != SelectableTextView.this) {
                    lastInstance.clean();
                    lastInstance = SelectableTextView.this;
                }

                int offset = getOffset(event);
                if ((offset < textOffsetEnd && offset > textOffsetStart)
                        || (offset > textOffsetEnd && offset < textOffsetStart)) {
                    if (textOffsetEnd - offset > offset - textOffsetStart)
                        textOffsetStart = textOffsetEnd;
                } else {
                    clean();
                    textOffsetStart = offset;
                }
                isDowned = true;
            } else if (isDowned && longCliked && action == MotionEvent.ACTION_MOVE) {
                selectTextOnMove(event);
            } else if (action == MotionEvent.ACTION_UP) {
                isDowned = false;
                longCliked = false;
            }
            if (lastOnTouch != null)
                lastOnTouch.onTouch(v, event);
            return false;
        }

    };
}

private void selectTextOnMove(MotionEvent event) {
    int offset = getOffset(event);
    if (offset != Integer.MIN_VALUE) {
        String text = getText().toString();
        SpannableStringBuilder sb = new SpannableStringBuilder(text);
        BackgroundColorSpan bgc = new BackgroundColorSpan(_SelectedBackgroundColor);
        ForegroundColorSpan textColor = new ForegroundColorSpan(_SelectedTextColor);

        int start = textOffsetStart;
        textOffsetEnd = offset;
        int end = offset;
        if (start > end) {
            int temp = start;
            start = end;
            end = temp;
        }
        int[] curectStartEnd = curectStartEnd(text, start, end);
        start = curectStartEnd[0];
        end = curectStartEnd[1];
        SelectableTextView.this.textSelectedStart = start;
        SelectableTextView.this.textSelectedEnd = end;
        sb.setSpan(bgc, start, end, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
        sb.setSpan(textColor, start, end, Spannable.SPAN_INCLUSIVE_INCLUSIVE);

        setText(sb);
    }
}

private int[] curectStartEnd(String text, int start, int end) {
    int length = text.length();

    while (start < length && start > 0 && text.charAt(start) != ' ') {
        start--;
    }
    while (end < length && text.charAt(end) != ' ') {
        end++;
    }
    return new int[] { start, end };
}

private int getOffset(MotionEvent event) {
    Layout layout = getLayout();
    if (layout == null)
        return Integer.MIN_VALUE;
    float x = event.getX() + getScrollX();
    float y = event.getY() + getScrollY();
    int line = layout.getLineForVertical((int) y);
    int offset = layout.getOffsetForHorizontal(line, x);
    return offset;
}

protected void clean() {
    if (this.getText() != null) {
        this.setText(this.getText().toString());
        textSelectedStart = 0;
        textSelectedEnd = 0;
    }
}

@Override
public int getSelectionStart() {
    return textSelectedStart;
}

@Override
public int getSelectionEnd() {
    return textSelectedEnd;
}

}

getOffset 获取触摸用户使用此组件设置这些属性的文本的选定偏移量:

        SelectableTextView textView1 = new SelectableTextView(context);
    textView1.setClickable(false);
    textView1.setCursorVisible(false);
    textView1.setOnTouchListener(getOnTextTouch());//new after text select touch
    textView1.setEnabled(this.selectable);
    textView1.setTextIsSelectable(this.selectable);

有人可以升级这个组件吗？

这是git hub中的代码

Answer 1

由于这个原因还添加了以下两个构造函数

    public SelectableTextView(Context context,AttributeSet attrs)
{
    super(context,attrs);
}

public SelectableTextView(Context context,AttributeSet attrs,int defStyle)
{
    super(context,attrs,defStyle);
}

我还在代码中添加了以下内容：

    @SuppressLint("NewApi")
public void setTextIsSelectable(boolean selectable) {
    if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.HONEYCOMB)
        super.setTextIsSelectable(true);
    else
    {   
        super.setLongClickable(true);
        super.setOnLongClickListener(getSelectableLongClick());
        super.setOnTouchListener(getSelectableOnTouch());
    }
}

我这样使用它，没有 OnTouchListener：

txt_copyFrom.setClickable(false);
txt_copyFrom.setCursorVisible(false);
txt_copyFrom.setEnabled(true);
txt_copyFrom.setTextIsSelectable(true);
txt_copyFrom.setOnLongClickListener(new OnLongClickListener(){

    @Override
    public boolean onLongClick(View v) {
        int start=txt_copyFrom.getSelectionStart();
        int end=txt_copyFrom.getSelectionEnd();

        mSelectedText=txt_copyFrom.getText().toString().substring(start, end);
        Log.d(TAG, "Selected text: "+mSelectedText);
        return true;
    }

});

与 XML：

<com.example.clipboardtest.SelectableTextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Old Buccaneer1The Old Sea-dog at the Admiral BenbowSquire Trelawney, Dr. Livesey, and the rest of these gentlemen having asked me to write down the whole particulars about Treasure Island, from the beginning to the end, keeping nothing back but the bearings of the island, and that only because there is still treasure not yet lifted, I take up my pen in the year of grace 17--and go back to the time when my father kept the Admiral Benbow inn and the brown old seaman with the sabre cut first took up his lodging under our roof."
    android:id="@+id/txt_copyfrom"
/>         

我想我必须在 Activity 本身的 TextViewOnTouchListener中设置一个。OnLongClickListener

尝试将日志放在 SelectableTextView 中的各处，它似乎不起作用...我发现 LongClickListener 被调用，但 TouchListener 甚至没有被调用...

在 OnLongClickListener 中设置 OnTouchListener 可以做到这一点