new Selectable TextView in android 3 (API

问题

After a long and time consuming search, I can't find a component that can select text in textview for android API level <=11. I have written this component that may be of help to you :

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 get the selected offset of text that Touched user for using this component set these attributes:

        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);

Can anyone upgrade this component?

This is the code in git hub

回答1:

Also add the following two constructors because of this

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

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

I have also added the following to the code:

    @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());
    }
}

I used it like this,without an 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;
    }

});

with the 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"
/>

I guess I have to set an OnTouchListener within the OnLongClickListener for the TextView in the Activity itself.

Tried putting Logs all over the place in SelectableTextView,it does not seem to be working...I find that the LongClickListener is called but the TouchListener is not even called...

Setting the OnTouchListener inside the OnLongClickListener did this

来源：https://stackoverflow.com/questions/18042308/new-selectable-textview-in-android-3-api-11-component

标签

android