自定义控件,可以伸缩的textview

项目需求，某些textview如果超过两行，需要隐藏，右边有个图片，点击可以张开查看全部内容，也可以点击收缩。

package zivixgroup.com.skilltemp.widget;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.View;
import zivixgroup.com.skilltemp.R;

/**
 * 可以伸展的textview
 * Created by george.yang on 2015/8/7.
 */
public class StretchTextView extends TextView implements View.OnClickListener {
    private int maxLines = 2;
    private boolean isSpread;//伸展状态
    private OnClickListener listener;
    private int spreadHeight;//展开时的高度


    public StretchTextView(Context context) {
        super(context);
        init(context);
    }

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


    public StretchTextView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context);
    }


    private void init (Context context) {
        setEllipsize(TextUtils.TruncateAt.END);//多余的变成...
        setMaxLines(maxLines);

        addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }

            @Override
            public void afterTextChanged(Editable editable) {
                postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        if (getLineCount() >= maxLines) {
                            setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_details_more, 0);
                        } else {
                            setCompoundDrawablesWithIntrinsicBounds(0, 0, 0, 0);
                        }
                    }
                }, 100);
            }
        });

        super.setOnClickListener(this);
    }


    @Override
    public void setOnClickListener(OnClickListener l) {
        listener = l;
    }


    @Override
    public void onClick(View view) {
        if (getLineCount()<maxLines) {
            return;
        }

        isSpread = !isSpread;
        if (isSpread) {
            this.setMaxLines(Integer.MAX_VALUE);
            this.requestLayout();

            if (spreadHeight==0) {
                setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_details_more, 0);
                postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        spreadHeight = getMeasuredHeight();
                        resetDrawable();
                    }
                },100);
            } else {
                resetDrawable();
            }
        } else  {
            this.setMaxLines(maxLines);
            this.requestLayout();

            spreadHeight = getMeasuredHeight();

            setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_details_more, 0);
        }

        if (listener!=null) {
            listener.onClick(view);
        }
    }

    private void resetDrawable() {
        Drawable drawable = getResources().getDrawable(R.drawable.ic_shrink_up);
        drawable.setBounds(0, spreadHeight/2-drawable.getIntrinsicHeight()/2, drawable.getIntrinsicWidth(),spreadHeight/2+drawable.getIntrinsicHeight()/2);
        setCompoundDrawables(null, null, drawable, null);
    }
}

ic_shrink_up

ic_details_more