带有单选按钮的 Android Action Down

Question

我目前正在尝试制作我的项目，以便选择其中一个单选按钮并保持按钮，然后它产生所选声音。但是，当我使用 ACTION_DOWN 函数时，不会产生噪音。任何帮助都会很棒

public boolean onTouch(View v, MotionEvent event) {
    int frequency = Integer.parseInt(frequencyInput.getText().toString());
    displayFrequency.setText(String.valueOf(frequency));
    sineWave.setSine(frequency);
    squareWave.setSquareWave(frequency);
    sawWave.setSawWave(frequency);
    boolean on = ((startStop.isPressed()) && sine.isChecked());
    boolean sqOn = ((startStop.isPressed()) && square.isChecked());
    boolean sawOn =((startStop.isPressed()) && saw.isChecked());
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            if (on)
            {
                sineWave.start();
            }
            else if (sqOn)
                {
                 squareWave.start();
                }

            else if (sawOn)
                  {
                sawWave.start();
            }
            break;

        case MotionEvent.ACTION_UP:
            if (!on) {
                sineWave.stop();
            }
            if (!sqOn) {
                squareWave.stop();
            }
            if (!sawOn) {
                sawWave.stop();
                ;
            }
            break;


            }

Answer 1

主要问题是您在onTouch 中时检查isPressed()，因此尚未设置按钮的按下状态。

如果您将onTouchListener 直接添加到startStop 按钮，您可以确定每次调用它都是触发事件的startStop 按钮。这允许您删除startStop.isPressed() 检查。

  startStop.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            int frequency = Integer.parseInt(frequencyInput.getText().toString());
            displayFrequency.setText(String.valueOf(frequency));
            sineWave.setSine(frequency);
            squareWave.setSquareWave(frequency);
            sawWave.setSawWave(frequency);
            boolean on = sine.isChecked();
            boolean sqOn = square.isChecked();
            boolean sawOn = saw.isChecked();
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    if (on) {
                        sineWave.start();
                    } else if (sqOn) {
                        squareWave.start();
                    } else if (sawOn) {
                        sawWave.start();
                    }
                    break;    
                case MotionEvent.ACTION_UP:
                    if (!on) {
                        sineWave.stop();
                    }
                    if (!sqOn) {
                        squareWave.stop();
                    }
                    if (!sawOn) {
                        sawWave.stop();
                    }
                    break;
                default:
                    return false;
            }
            return true;
        }
    });