计时器无法解决方法

Question

I am having an issue in setting up my Chronometer. The Java file shows an error at "updateTimerText" stating Cannot resolve method "updateTimerText (java.lang.string) How do I solve this? Everything is Fine on the fragment I am trying to cast this task to it is just the Chronometer.java file. If you need any other information or code, let me know. Thanks in advance.

package com.example.platinumirish.runassistwithdrawer;

import android.content.Context;

import runassist.demo.fragments.MainFragment;

/**
 * Created by Platinum Irish on 22/06/2016.
 */
public class Chronometer implements Runnable {

    public static final long MILLIS_TO_MINUTES = 60000;
    public static final long MILLIS_TO_HOURS = 3600000;

    private Context mContext;
    private long mStartTime;

    private boolean mIsRunning;

    public Chronometer(Context context){
        mContext = context;
    }

    public void start() {
        mStartTime = System.currentTimeMillis();
        mIsRunning = true;

    }

    public void stop() {

        mIsRunning = false;

    }

    @Override
    public void run() {

        while(mIsRunning) {

            long since = System.currentTimeMillis() - mStartTime;

                int seconds = (int) (since / 1000 % 60);
                int minutes = (int)(((since / MILLIS_TO_MINUTES)) % 60);
                int hours = (int)((since / (MILLIS_TO_HOURS)) % 24);
                int millis = (int) since % 1000;

                MainFragment mainFragment = (MainFragment) mContext.updateTimerText(String.format(
                    "%02d;%02d;%02d;%03d", hours, minutes, seconds, millis

            ));
        }

    }
}

Here is my Main Fragment too if it will help in any way, shape or form.

package runassist.demo.fragments;

import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Chronometer;
import android.widget.TextView;

import com.example.platinumirish.runassistwithdrawer.R;


public class MainFragment extends Fragment{

private TextView mTvTime;
private Button mBtnStart;
private Button mBtnStop;

private Context mContext;
private Chronometer mChronometer;
private Thread mThreadChrono;


@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_main, container, false);

    mTvTime = (TextView) rootView.findViewById(R.id.chronometer);
    mBtnStart = (Button) rootView.findViewById(R.id.start_button);
    mBtnStop = (Button) rootView.findViewById(R.id.stop_button);

    mBtnStart.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            if(mChronometer == null) {
                mChronometer = new Chronometer(mContext);
                mThreadChrono = new Thread((Runnable) mChronometer);
                mThreadChrono.start();
                mChronometer.start();
            }
        }
    });

    mBtnStop.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if(mChronometer !=null) {
                mChronometer.stop();
                mThreadChrono.interrupt();
                mThreadChrono = null;

                mChronometer = null;
            }

        }
    });

    return rootView;

}

public void updateTimerText(final String time) {
    runOnUiThread(new Runnable() {

        @Override
        public void run () {
            mTvTime.setText(time);
        }

    });
}

private void runOnUiThread(Runnable runnable) {
}

}

Answer 1

((MainFragment) mContext).updateTimerText(...) this is the way you want to call it. Check the squares around mContext. Also, your method updateTimerText returns void so this line:

MainFragment mainFragment = (MainFragment) mContext.updateTimerText(String.format(
                "%02d;%02d;%02d;%03d", hours, minutes, seconds, millis))

will raise another error. It should simply be:

((MainFragment) mContext).updateTimerText(...)

I can't help it, I have to suggest to use a different approach, first of all it's a bad idea to keep a reference to the context in a Runnable class.

Second of all, it's bad to cast Context to either Activity or Fragment , it will reduce the code reusability and cause unexpected crashes if the dev is not aware of this casts.