Android中设置用户的头像

在开发中我们经常会遇到为用户设置自定义头像的功能，下面我介绍一下如何实现这一功能：

具体代码如下：

package com.example.seticon;

import java.io.File;

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

public class MainActivity extends Activity {

	private Button mFromAlbum; // 从相册选取
	private Button mTakePhotos; // 照相
	private ImageView mImgView;
	private final int FROM_ALBUM = 0;
	private final int FROM_TAKE_PHOTOS = 1;
	private final int PHOTO_CUT = 2;
	private final String FILE_NAME = "tempimg.jpg";
	private File tempFile;
	private Bitmap bitmap;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mImgView = (ImageView) findViewById(R.id.img);
		mFromAlbum = (Button) findViewById(R.id.fromAlbum);
		mTakePhotos = (Button) findViewById(R.id.takePhoto);
		//从相册选取照片
		mFromAlbum.setOnClickListener(new OnClickListener() {

			public void onClick(View v) {
				// TODO Auto-generated method stub
				Intent intent = new Intent(Intent.ACTION_PICK);
				intent.setType("image/*");
				startActivityForResult(intent, FROM_ALBUM);
			}
		});
		//即时拍摄头像
		mTakePhotos.setOnClickListener(new OnClickListener() {

			public void onClick(View v) {
				// TODO Auto-generated method stub
				Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
				// 判断存储卡是否可以用，可用进行存储
				if (Environment.getExternalStorageState().equals(
						Environment.MEDIA_MOUNTED)) {
					intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri
							.fromFile(new File(Environment
									.getExternalStorageDirectory(), FILE_NAME)));
				}
				startActivityForResult(intent, FROM_TAKE_PHOTOS);
			}
		});
	}

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		// TODO Auto-generated method stub
		switch (requestCode) {
		case FROM_ALBUM:
			if (data != null) {
				// 取到照片路径
				Uri uri = data.getData();
				editPic(uri);
			}
			break;
		case FROM_TAKE_PHOTOS:
			if (Environment.getExternalStorageState().equals(
					Environment.MEDIA_MOUNTED)) {
				tempFile = new File(Environment.getExternalStorageDirectory(),
						FILE_NAME);
				editPic(Uri.fromFile(tempFile));
			} else {
				Toast.makeText(MainActivity.this, "未找到存储卡！", 0).show();
			}
			break;
		case PHOTO_CUT:
			try {
				bitmap = data.getParcelableExtra("data");
				mImgView.setImageBitmap(bitmap);
				//删除缓存图片
				tempFile.delete();
			} catch (Exception e) {
				e.printStackTrace();
			}
			break;
		}
		super.onActivityResult(requestCode, resultCode, data);

	}

	/** 编辑选中的照片 */
	private void editPic(Uri uri) {
		Intent intent = new Intent("com.android.camera.action.CROP");
		intent.setDataAndType(uri, "image/*");
		intent.putExtra("crop", "true");
		// 裁剪框的比例，1：1
		intent.putExtra("aspectX", 1);
		intent.putExtra("aspectY", 1);
		// 裁剪后输出图片的尺寸大小
		intent.putExtra("outputX", 250);
		intent.putExtra("outputY", 250);
		intent.putExtra("outputFormat", "JPEG");
		intent.putExtra("noFaceDetection", true);
		intent.putExtra("return-data", true);
		startActivityForResult(intent, PHOTO_CUT);
	}
}

xml布局文件如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/fromAlbum"
        android:layout_width="150dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="从相册选取" />

    <Button
        android:id="@+id/takePhoto"
        android:layout_width="150dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="拍照" />

    <ImageView
        android:id="@+id/img"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp" />

</LinearLayout>

所用到的权限有：

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