Previewing VideoRecording Not working Listings 11-9 to 11-10

rinkle · June 18th, 2010, 07:29 AM

Hi I'm trying to get the Videorecording/previewing to work but i keep getting errors.

heres what i've done:

manifest.xml

Code:

<uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>
<uses-permission android:name="android.permission.RECORD_VIDEO"></uses-permission>

camera_preview.xml

Code:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="horizontal"> 
 
<SurfaceView 
android:id="@+id/SurfaceView01" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent">
</SurfaceView>
</RelativeLayout>

VideoCamera.java

Code:

package se.rijad.android.nikita.ui;

import java.io.IOException;

import se.rijad.android.nikita.R;
import android.app.Activity;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;

public class VideoCamera extends Activity implements SurfaceHolder.Callback
{
	private MediaRecorder mediaRecorder;
	
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
    
        super.onCreate(savedInstanceState);
        //requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.video_camera);
	
        SurfaceView surface = (SurfaceView)findViewById(R.id.SurfaceView01);
        SurfaceHolder holder = surface.getHolder();
        holder.addCallback(this);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        holder.setFixedSize(400,300);
    }
    
	public void surfaceCreated(SurfaceHolder holder) {
		if (mediaRecorder == null){
			try {
				mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
				mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
				
				//PREF THIS!
				//mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
				mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
				//mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
				
				mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
				mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H263);
				
				mediaRecorder.setOutputFile("/sdcard/nikita_video_output.mp4");
				
				mediaRecorder.setPreviewDisplay(holder.getSurface());
				mediaRecorder.prepare();
			} catch (IllegalArgumentException e) {
				Log.d("NIKITA{MEDIA_PLAYER}", e.getMessage());
			} catch (IllegalStateException e) {
				Log.d("NIKITA{MEDIA_PLAYER}", e.getMessage());
			} catch (IOException e) {
				Log.d("NIKITA{MEDIA_PLAYER}", e.getMessage());
			}
		}
	}

	public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
		// TODO Auto-generated method stub
	}

	public void surfaceDestroyed(SurfaceHolder holder) {
		mediaRecorder.release();
	}
	
}

Logcat

Code:

06-18 14:11:46.495: ERROR/AndroidRuntime(3458): Uncaught handler: thread main exiting due to uncaught exception
06-18 14:11:46.505: ERROR/AndroidRuntime(3458): java.lang.RuntimeException: Unable to start activity ComponentInfo{se.rijad.android.nikita/se.rijad.android.nikita.ui.VideoCamera}: java.lang.NullPointerException
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2596)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2621)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread.access$2200(ActivityThread.java:126)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1932)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.os.Looper.loop(Looper.java:123)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread.main(ActivityThread.java:4595)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at java.lang.reflect.Method.invokeNative(Native Method)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at java.lang.reflect.Method.invoke(Method.java:521)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at dalvik.system.NativeStart.main(Native Method)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458): Caused by: java.lang.NullPointerException
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at se.rijad.android.nikita.ui.VideoCamera.onCreate(VideoCamera.java:24)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2544)
06-18 14:11:46.505: ERROR/AndroidRuntime(3458):     ... 11 more

VideoCamera.jva:24

Code:

SurfaceView surface = (SurfaceView)findViewById(R.id.surface);
	    SurfaceHolder holder = surface.getHolder();
24:	    holder.addCallback(this);  //Null? :(
	    holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
	    holder.setFixedSize(400, 300);

please help.

Reto · June 21st, 2010, 01:03 PM

From a quick look, it appears I've missed a line of code. The mediaRecorder variable is never being initialized.

Try adding:

Code:

mediaRecorder = new MediaRecorder();

Immediately before modifying the mediaRecorder parameters within the surfaceCreated method.