调用SeekBar.getProgress（）;从另一个班级不回报任何东西？

Question

我有一个带有片段对象的类;并且该片段对象包含几个搜索栏。

为了从片段中获取seekbar的值，我在main活动中实例化了fragmentObject并调用了fragmentObject.seekBar.getProgress（）;

然而;这不会返回什么？

主要活动代码：

//loops repeatedly
public void loop() throws ConnectionLostException, InterruptedException {

    float f = ((float)fragmentObject.pwm1Seek.getProgress()/330);

    }
}

相关片段代码：

    package com.example.ioiorun;

import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.SeekBar;
import android.widget.Switch;
import android.widget.TextView;
import android.support.v4.app.Fragment;

public class fragmentExample extends Fragment {
    String TAG;
    // Declare all the UI Variables
    View fragmentView;

        SeekBar pwm1Seek;


    public View onCreateView(LayoutInflater viewInflation, ViewGroup container,
            Bundle SavedInstantState) {

        fragmentView = viewInflation.inflate(R.layout.pwmfragment_page,
                container, false);
        pwm1Seek = (SeekBar) pwmFragmentView.findViewById(R.id.pwm1SeekBar);

        pwm1Seek.setMax(330);


        pwm1Seek.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress,
                    boolean fromUser) {
                // TODO Auto-generated method stub
                float f = (float)progress/100;
                pwm1Voltage.setText("Voltage: " + String.valueOf(f));
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
                // TODO Auto-generated method stub
            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                // TODO Auto-generated method stub
            }
        });


        _mainactivity.setCurrentPWMFragment(this);

        return fragmentView;
    }

    public View getFragmentView() {
        return fragmentView;
    }

    public void setFragmentView(View fragmentView) {
        this.fragmentView = fragmentView;
    }
}

Answer 1

我发现了我的错误;我错误地在我的其他类中实例化我的片段对象。