I am trying to learn how to make a simple app in android. As background information I have only programmed in C language, no OOP.

Currently I am trying turn on the camera using the indications from Android Developer site but some minor changes: - no button for capturing image. - no new activity.

What I am trying to do is jut preview the camera. I will post the Code that I am using, the manifest and the LogCat.

Main Activity:

package com.example.camera_display;

import android.app.Activity;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.Menu;
import android.widget.FrameLayout;
import android.widget.TextView;

public class MainActivity extends Activity {

    private Camera mcamera;
    private CameraPreview mCameraPreview;

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

        mcamera = getCameraInstance();

        mCameraPreview = new CameraPreview(this, mcamera);
        FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); 
        preview.addView(mCameraPreview);


    }

    public static Camera getCameraInstance(){
        Camera c = null;
        try {
            c = Camera.open(); // attempt to get a Camera instance
        }
        catch (Exception e){
            // Camera is not available (in use or does not exist)
        }
        return c; // returns null if camera is unavailable
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

CameraPreview Class:

package com.example.camera_display;

import java.io.IOException;

import android.content.Context;
import android.hardware.Camera;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

/** A basic Camera preview class */
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
    private static final String TAG = "MyActivity";
    private SurfaceHolder mHolder;
    private Camera mCamera;

    public CameraPreview(Context context, Camera camera) {
        super(context);
        mCamera = camera;

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        mHolder = getHolder();
        mHolder.addCallback(this);
        // deprecated setting, but required on Android versions prior to 3.0
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void surfaceCreated(SurfaceHolder holder) {      
        // The Surface has been created, now tell the camera where to draw the preview.
        try {
            mCamera.setPreviewDisplay(holder);
            mCamera.startPreview();
        } catch (IOException e) {
            Log.d(TAG, "Error setting camera preview: " + e.getMessage());
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // empty. Take care of releasing the Camera preview in your activity.
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // If your preview can change or rotate, take care of those events here.
        // Make sure to stop the preview before resizing or reformatting it.

        if (mHolder.getSurface() == null){
          // preview surface does not exist
          return;
        }

        // stop preview before making changes
        try {
            mCamera.stopPreview();
        } catch (Exception e){
          // ignore: tried to stop a non-existent preview
        }

        // set preview size and make any resize, rotate or
        // reformatting changes here

        // start preview with new settings
        try {
            mCamera.setPreviewDisplay(mHolder);
            mCamera.startPreview();

        } catch (Exception e){
            Log.d(TAG, "Error starting camera preview: " + e.getMessage());
        }
    }
}

Manifest:

<uses-permission 
        android:name="android.permission.CAMERA"/>
    <uses-feature 
        android:name="android.hardware.camera"/>

LOG CAT:

06-30 15:58:35.075: D/libEGL(1153): loaded /system/lib/egl/libEGL_emulation.so
06-30 15:58:35.147: D/(1153): HostConnection::get() New Host Connection established 0x2a156060, tid 1153
06-30 15:58:35.478: D/libEGL(1153): loaded /system/lib/egl/libGLESv1_CM_emulation.so
06-30 15:58:35.515: D/libEGL(1153): loaded /system/lib/egl/libGLESv2_emulation.so
06-30 15:58:36.334: W/EGL_emulation(1153): eglSurfaceAttrib not implemented
06-30 15:58:36.685: D/OpenGLRenderer(1153): Enabling debug mode 0
06-30 15:58:36.935: D/MyActivity(1153): Error starting camera preview: startPreview failed
06-30 15:58:36.965: I/Choreographer(1153): Skipped 125 frames!  The application may be doing too much work on its main thread.
06-30 15:58:38.455: W/Camera(1153): Camera server died!
06-30 15:58:38.455: W/Camera(1153): ICamera died
06-30 15:58:38.476: E/Camera(1153): Error 100

So If anyone could tell me what I am doing wrong (and explain why it should be done different) that would be great :)

Thanks!