android - 必须从 UI 线程调用方法 loadVideoFromAsset

Question

我正在尝试在我的项目中实现 360 视频查看器，但我收到以下行错误：

mVrVideoView.loadVideoFromAsset("sea.mp4", options);

这是错误

Method loadVideoFromAsset must be called from the UI thread, currently inferred 
thread is worker

以下是我的代码：

package com.example.jal.jp;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
import android.widget.SeekBar;

import com.google.vr.sdk.widgets.video.VrVideoEventListener;
import com.google.vr.sdk.widgets.video.VrVideoView;

import java.io.IOException;

public abstract class VR_Video extends AppCompatActivity implements SeekBar.OnSeekBarChangeListener {

    private VrVideoView mVrVideoView;
    private SeekBar mSeekBar;
    private Button mVolumeButton;

    private boolean mIsPaused;
    private boolean mIsMuted;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_vr__video);

        initViews();

    }
    public void onPlayPausePressed() {

    }

    public void onVolumeToggleClicked() {

    }

    @Override
    public void onProgressChanged(SeekBar seekBar, int i, boolean b) {

    }

    private void initViews() {
        mVrVideoView = (VrVideoView) findViewById(R.id.video_view);
        mSeekBar = (SeekBar) findViewById(R.id.seek_bar);
        mVolumeButton = (Button) findViewById(R.id.btn_volume);
        mVrVideoView.setEventListener(new ActivityEventListener());
        mSeekBar.setOnSeekBarChangeListener(this);
        mVolumeButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                onVolumeToggleClicked();
            }
        });
    }
    class VideoLoaderTask extends AsyncTask<Void, Void, Boolean> {

        @Override
        protected Boolean doInBackground(Void... voids) {
            try {
                VrVideoView.Options options = new VrVideoView.Options();
                options.inputType = VrVideoView.Options.TYPE_MONO;
                mVrVideoView.loadVideoFromAsset("sea.mp4", options);
            } catch( IOException e ) {
                //Handle exception
            }

            return true;
        }
    }
    public void playPause() {

    }
    @Override
    protected void onPause() {
        super.onPause();
        mVrVideoView.pauseRendering();
        mIsPaused = true;
    }

    @Override
    protected void onResume() {
        super.onResume();
        mVrVideoView.resumeRendering();
        mIsPaused = false;
    }

    @Override
    protected void onDestroy() {
        mVrVideoView.shutdown();
        super.onDestroy();
    }
    private class ActivityEventListener extends VrVideoEventListener {
        @Override
        public void onLoadSuccess() {
            super.onLoadSuccess();
        }

        @Override
        public void onLoadError(String errorMessage) {
            super.onLoadError(errorMessage);
        }

        @Override
        public void onClick() {
            super.onClick();
        }

        @Override
        public void onNewFrame() {
            super.onNewFrame();
        }

        @Override
        public void onCompletion() {
            super.onCompletion();
        }
    }
}

请帮忙。我尽力了，但无法修复。

Answer 1

从 UI 线程中删除 AsyncTask 实现并调用所需的方法

使用下面的代码：

private void initViews() {
    mVrVideoView = (VrVideoView) findViewById(R.id.video_view);
    mSeekBar = (SeekBar) findViewById(R.id.seek_bar);
    mVolumeButton = (Button) findViewById(R.id.btn_volume);
    mVrVideoView.setEventListener(new ActivityEventListener());
    try {
            VrVideoView.Options options = new VrVideoView.Options();
            options.inputType = VrVideoView.Options.TYPE_MONO;
            mVrVideoView.loadVideoFromAsset("sea.mp4", options);
        } catch( IOException e ) {
            //Handle exception
        }
    mSeekBar.setOnSeekBarChangeListener(this);
    mVolumeButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            onVolumeToggleClicked();
        }
    });
}

Answer 2

I dont know much about videoview but I show in your code that you are trying to access some the features in doInbackground method. The doINbackground method runs on a separate thread from the UI thread so that complex ant time consuming tasks do not block the UI thread. You can implement the features you are implementing in doINbackground method in the onCreate method or if you still need to use doInbackground you can access the UI thread inside doInbackground using runOnUiThread as follows

runOnUiThread(new Runnable() { @Override public void run() { //your code here } });