Android VideoViewアクティビティがクラッシュする

Question

ここではチュートリアル（https://examples.javacodegeeks.com/android/android-videoview-example/）を使用して、アプリを開いたときにクラッシュしてもビデオビューのアクティビティを構築しました。私は人生を救うためにそれを理解できません。私はここの他の記事をチェックしましたし、提案のどれもあなたのコードで

import android.app.Activity; 
import android.app.ProgressDialog; 
import android.content.res.Configuration; 
import android.media.MediaPlayer; 
import android.media.MediaPlayer.OnPreparedListener; 
import android.net.Uri; 
import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.util.Log; 
import android.widget.MediaController; 
import android.widget.VideoView; 

public class DemoActivity extends AppCompatActivity { 

    private VideoView myVideoView; 
    private int position = 0; 
    private ProgressDialog progressDialog; 
    private MediaController mediaControls; 


    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_quote); 
     Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
     setSupportActionBar(toolbar); 

     // set the main layout of the activity 
     setContentView(R.layout.activity_main); 

     //set the media controller buttons 
     if (mediaControls == null) { 
      mediaControls = new MediaController(DemoActivity.this); 
     } 

     //initialize the VideoView 
     myVideoView = (VideoView) findViewById(R.id.video_view); 

     // create a progress bar while the video file is loading 
     progressDialog = new ProgressDialog(DemoActivity.this); 
     // set a title for the progress bar 
     progressDialog.setTitle("JavaCodeGeeks Android Video View Example"); 
     // set a message for the progress bar 
     progressDialog.setMessage("Loading..."); 
     //set the progress bar not cancelable on users' touch 
     progressDialog.setCancelable(false); 
     // show the progress bar 
     progressDialog.show(); 

     try { 
      //set the media controller in the VideoView 
      myVideoView.setMediaController(mediaControls); 

      //set the uri of the video to be played 
      myVideoView.setVideoURI(Uri.parse("android.resource://" + getPackageName() + "/" + R.raw.demo)); 

     } catch (Exception e) { 
      Log.e("Error", e.getMessage()); 
      e.printStackTrace(); 
     } 

     myVideoView.requestFocus(); 
     //we also set an setOnPreparedListener in order to know when the video file is ready for playback 
     myVideoView.setOnPreparedListener(new OnPreparedListener() { 

      public void onPrepared(MediaPlayer mediaPlayer) { 
       // close the progress bar and play the video 
       progressDialog.dismiss(); 
       //if we have a position on savedInstanceState, the video playback should start from here 
       myVideoView.seekTo(position); 
       if (position == 0) { 
        myVideoView.start(); 
       } else { 
        //if we come from a resumed activity, video playback will be paused 
        myVideoView.pause(); 
       } 
      } 
     }); 

    } 

    @Override 
    public void onSaveInstanceState(Bundle savedInstanceState) { 
     super.onSaveInstanceState(savedInstanceState); 
     //we use onSaveInstanceState in order to store the video playback position for orientation change 
     savedInstanceState.putInt("Position", myVideoView.getCurrentPosition()); 
     myVideoView.pause(); 
    } 

    @Override 
    public void onRestoreInstanceState(Bundle savedInstanceState) { 
     super.onRestoreInstanceState(savedInstanceState); 
     //we use onRestoreInstanceState in order to play the video playback from the stored position 
     position = savedInstanceState.getInt("Position"); 
     myVideoView.seekTo(position); 
    } 
} 

Answer 1

は、2つのレイアウトのための2つのsetContentView()を持っていませんでした。それがあなたの誤りの理由です。 mergeのレイアウトが2つあり、そのビューでVideoViewが利用可能であることを確認してください。