在电商类app的购物车页面，经常会有这样的需求：长按“+”按钮或者“-”按钮时，购物车中的商品数量连续的增加或减少。
本例的目的就是为了实现这个效果。预览图：
1.自定义Button.
/** * 长按连续响应的Button * Created by admin on 15-6-1. */public class LongClickButton extends Button { /** * 长按连续响应的监听，长按时将会多次调用该接口中的方法直到长按结束 */ private LongClickRepeatListener repeatListener; /** * 间隔时间（ms） */ private long intervalTime; private MyHandler handler; public LongClickButton(Context context) { super(context); init(); } public LongClickButton(Context context, AttributeSet attrs) { super(context, attrs); init(); } public LongClickButton(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(); } /** * 初始化监听 */ private void init() { handler = new MyHandler(this); setOnLongClickListener(new OnLongClickListener() { @Override public boolean onLongClick(View v) { new Thread(new LongClickThread()).start(); return true; } }); } /** * 长按时，该线程将会启动 */ private class LongClickThread implements Runnable { private int num; @Override public void run() { while (LongClickButton.this.isPressed()) { num++; if (num % 5 == 0) { handler.sendEmptyMessage(1); } SystemClock.sleep(intervalTime / 5); } } } /** * 通过handler，使监听的事件响应在主线程中进行 */ private static class MyHandler extends Handler { private WeakReference<LongClickButton> ref; MyHandler(LongClickButton button) { ref = new WeakReference<>(button); } @Override public void handleMessage(Message msg) { super.handleMessage(msg); LongClickButton button = ref.get(); if (button != null && button.repeatListener != null) { button.repeatListener.repeatAction(); } } } /** * 设置长按连续响应的监听和间隔时间，长按时将会多次调用该接口中的方法直到长按结束 * * @param listener 监听 * @param intervalTime 间隔时间（ms） */ public void setLongClickRepeatListener(LongClickRepeatListener listener, long intervalTime) { this.repeatListener = listener; this.intervalTime = intervalTime; } /** * 设置长按连续响应的监听（使用默认间隔时间100ms），长按时将会多次调用该接口中的方法直到长按结束 * * @param listener 监听 */ public void setLongClickRepeatListener(LongClickRepeatListener listener) { setLongClickRepeatListener(listener, 100); } public interface LongClickRepeatListener { void repeatAction(); }}2.在Activity中调用：LongClickButton buttonSub = (LongClickButton) findViewById(R.id.long_click_button1); LongClickButton buttonAdd = (LongClickButton) findViewById(R.id.long_click_button2); final TextView numberTV = (TextView) findViewById(R.id.main_number); //连续减 buttonSub.setLongClickRepeatListener(new LongClickButton.LongClickRepeatListener() { @Override public void repeatAction() { numberTV.setText(String.valueOf(Integer.parseInt(numberTV.getText().toString()) - 1)); } }, 50); //连续加 buttonAdd.setLongClickRepeatListener(new LongClickButton.LongClickRepeatListener() { @Override public void repeatAction() { numberTV.setText(String.valueOf(Integer.parseInt(numberTV.getText().toString()) + 1)); } }, 50); //减1 buttonSub.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { numberTV.setText(String.valueOf(Integer.parseInt(numberTV.getText().toString()) - 1)); } }); //加1 buttonAdd.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { numberTV.setText(String.valueOf(Integer.parseInt(numberTV.getText().toString()) + 1)); } });