安卓中选择系统图库的图片及调用相机的源码（原创）

在Android开发中经常会用到图片的上传功能，一般常用的是调用Android系统自带的图库及拍照功能。示例代码如下：

在MainActivity.java中

import java.io.ByteArrayOutputStream;
import java.io.File;

import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {
	private Button btn1,btn2;
	private ImageView img;
	public final static int PHOTO_ZOOM = 0;
    public final static int TAKE_PHOTO = 1;
    public final static int PHOTO_RESULT = 2;
    public static final String IMAGE_UNSPECIFIED = "image/*";
    private String imageDir;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		img = (ImageView) findViewById(R.id.avatar);
		btn1 = (Button) findViewById(R.id.selector);
		btn2 = (Button) findViewById(R.id.paizhao);
		btn1.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				 Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
	             intent.setType(IMAGE_UNSPECIFIED);
	             Intent wrapperIntent=Intent.createChooser(intent, null);
	             startActivityForResult(wrapperIntent, PHOTO_ZOOM);
			}
		});
		btn2.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				 imageDir = "temp.jpg";
	             Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
	                intent.putExtra(MediaStore.EXTRA_OUTPUT,
	                        Uri.fromFile(new File(Environment.getExternalStorageDirectory(), imageDir)));
	                startActivityForResult(intent, TAKE_PHOTO);
			}
		});
	}
	// 图片缩放
	public void photoZoom(Uri uri) {
	        Intent intent = new Intent("com.android.camera.action.CROP");
	        intent.setDataAndType(uri, IMAGE_UNSPECIFIED);
	        intent.putExtra("crop", "true");
	        // aspectX aspectY 是宽高的比例
	        intent.putExtra("aspectX", 1);
	        intent.putExtra("aspectY", 1);
	        // outputX outputY 是裁剪图片宽高
	        intent.putExtra("outputX", 250);
	        intent.putExtra("outputY", 250);
	        intent.putExtra("return-data", true);
	        startActivityForResult(intent, PHOTO_RESULT);
	    }
	
	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		if (resultCode == RESULT_OK) {
            if (requestCode == PHOTO_ZOOM) {
                photoZoom(data.getData());
            }
            if (requestCode == TAKE_PHOTO) {
                File picture = new File(Environment.getExternalStorageDirectory() + "/" + imageDir);
                photoZoom(Uri.fromFile(picture));
            }

            if (requestCode == PHOTO_RESULT) {
                Bundle extras = data.getExtras();
                if (extras != null) {
                    Bitmap photo = extras.getParcelable("data");
                    ByteArrayOutputStream stream = new ByteArrayOutputStream();
                    photo.compress(Bitmap.CompressFormat.JPEG, 75, stream);
                    img.setImageBitmap(photo);
                }
            }
        }
		super.onActivityResult(requestCode, resultCode, data);
	}
	


}

activity_main.xml中

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#fcf3ef"
    android:orientation="vertical" 
    android:gravity="center_horizontal"
    android:padding="30dp"
    >
	<ImageView
        android:id="@+id/avatar"
        android:layout_width="130dp"
        android:layout_height="130dp"
        android:background="@drawable/ic_launcher" />
	<LinearLayout 
	    android:layout_width="match_parent"
	    android:layout_height="wrap_content"
	    android:orientation="horizontal">
	    <Button 
	        android:id="@+id/selector"
	        android:layout_height="wrap_content"
	        android:layout_width="0dp"
	        android:layout_weight="1"
	        android:gravity="center"
	        android:text="本地选择"/>
	    <Button
	        android:id="@+id/paizhao" 
	        android:layout_height="wrap_content"
	        android:layout_width="0dp"
	        android:layout_weight="1"
	        android:text="拍照"/>
	</LinearLayout>
    

</LinearLayout>

效果如图：

因为时间关系，界面就谁便做了，请见谅！！！！！！！！！！！！！！！！！！！！