Android开发之调用系统图库及相机

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：

Java代码：

public class TestActivity extends Activity {

    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;
private ImageView avatar;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.main);

        avatar = (ImageView) findViewById(R.id.avatar);
 	   // 本地图库选择按钮
        LinearLayout upload = 
(LinearLayout)findViewById(R.id.local_select_button);
        upload.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);
            }
        });
   // 拍照按钮
        LinearLayout takePhoto=
(LinearLayout)findViewById(R.id.take_photo_button);
        takePhoto.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);
                    avatar.setImageBitmap(photo);
                }
            }
        }
        super.onActivityResult(requestCode, resultCode, data);
}

}

　　布局文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#fcf3ef"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:paddingTop="30dp" >

    <ImageView
        android:id="@+id/avatar"
        android:layout_width="130dp"
        android:layout_height="130dp"
        android:background="@drawable/avatar_frame" />

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp"
        android:gravity="center_horizontal" >

        <LinearLayout
            android:id="@+id/local_select_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="@drawable/local" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="10dp"
                android:text="本地选择"
                android:textColor="#000000"
                android:textSize="20sp" />
        </LinearLayout>

        <LinearLayout
            android:id="@+id/take_photo_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="50dp"
            android:gravity="center"
            android:orientation="vertical" >

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="@drawable/take_photo" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="10dp"
                android:text="拍照"
                android:textColor="#000000"
                android:textSize="20sp" />
        </LinearLayout>
</LinearLayout>
</LinearLayout>

　　

布局文件效果图如下：

本地选择效果图如下：

相机拍照效果如下：

图片缩放效果图：

图片上传结果效果图：