Question

如何长按按钮发送字符流。这是按钮LongClick上的代码，

btnDown.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View v) {
            sendMessage("S");//Here I wanted to send for example SSSSS on long press of that button
        }
    });

我想长按一个按钮发送一串字符，直到用户释放按钮。

Answer 1

尝试这样做自定义Listner

    String mString="";

public class ContinousRepeatListener implements View.OnTouchListener {

private Handler handler = new Handler();

private int initialInterval;
private final int normalInterval;
private final View.OnClickListener clickListener;

private Runnable handlerRunnable = new Runnable() {
    @Override
    public void run() {
        handler.postDelayed(this, normalInterval);
        clickListener.onClick(downView);
    }
};

private View downView;

/**
 * @param initialInterval The interval after first click event
 * @param normalInterval The interval after second and subsequent click 
 *       events
 * @param clickListener The OnClickListener, that will be called
 *       periodically
 */
public ContinousRepeatListener (int initialInterval, int normalInterval, 
        View.OnClickListener clickListener) {
    if (clickListener == null)
        throw new IllegalArgumentException("null runnable");
    if (initialInterval < 0 || normalInterval < 0)
        throw new IllegalArgumentException("negative interval");

    this.initialInterval = initialInterval;
    this.normalInterval = normalInterval;
    this.clickListener = clickListener;
}

public boolean onTouch(View view, MotionEvent motionEvent) {
    switch (motionEvent.getAction()) {
    case MotionEvent.ACTION_DOWN:
        handler.removeCallbacks(handlerRunnable);
        handler.postDelayed(handlerRunnable, initialInterval);
        downView = view;
        downView.setPressed(true);
        clickListener.onClick(view);
        return true;
    case MotionEvent.ACTION_UP:
    case MotionEvent.ACTION_CANCEL:
        handler.removeCallbacks(handlerRunnable);
        downView.setPressed(false);
        downView = null;
        return true;
    }

    return false;
}

}

并像这样使用

 btnDown.setOnTouchListener(new ContinousRepeatListener(400, 100, new  View.OnClickListener() {
        @Override
        public void onClick(View view) {
            // the code to execute repeatedly
            mString += "S";
            tvString.setText(mString);
        }
    }));

Answer 2

使用setOnTouchListener并在ACTION_DOWN上编写sendMessage代码

如何在长按按钮时发送字符流

2 个答案: