Android更换头像功能实现

现在不管什么APP都有个头像，如果你看见没有头像的APP就会感觉非常奇怪，以前头像都是方的，后来就变成圆的，我估计在过个几年就得来个五角星形状的头像，下面我把更换头像的代码写来：

<RelativeLayout 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"
    tools:context=".MainActivity" >

    <ImageView
        android:id="@+id/iv_head"
        android:layout_width="200dip"
        android:layout_height="200dip"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="210dip"
        android:src="@drawable/ic_launcher" />

    <Button
        android:id="@+id/btn_takephoto"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:text="拍照" />

    <Button
        android:id="@+id/btn_photos"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:text="从相册取" />

</RelativeLayout>

首先我定义了一个非常简单的XML布局，里面两个Button，一个ImageView用来显示头像：

下面我来看看MainActivity代码：

package com.example.changhead;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;


import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

@SuppressLint("SdCardPath")
public class MainActivity extends Activity implements OnClickListener {
  private ImageView ivHead;//头像显示
  private Button btnTakephoto;//拍照
  private Button btnPhotos;//相册
  private Bitmap head;//头像Bitmap
  private static String path="/sdcard/myHead/";//sd路径

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

  private void initView() {
    //初始化控件
    btnPhotos = (Button) findViewById(R.id.btn_photos);
    btnTakephoto = (Button) findViewById(R.id.btn_takephoto);
    btnPhotos.setOnClickListener(this);
    btnTakephoto.setOnClickListener(this);
    ivHead = (ImageView) findViewById(R.id.iv_head);
    Bitmap bt = BitmapFactory.decodeFile(path + "head.jpg");//从Sd中找头像，转换成Bitmap
    if(bt!=null){
      @SuppressWarnings("deprecation")
      Drawable drawable = new BitmapDrawable(bt);//转换成drawable
      ivHead.setImageDrawable(drawable);
    }else{
      /**
       *  如果SD里面没有则需要从服务器取头像，取回来的头像再保存在SD中
       * 
       */
    }



  }

  @Override
  public void onClick(View v) {
    switch (v.getId()) {
    case R.id.btn_photos://从相册里面取照片
      Intent intent1 = new Intent(Intent.ACTION_PICK, null);
      intent1.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
      startActivityForResult(intent1, 1);
      break;
    case R.id.btn_takephoto://调用相机拍照
      Intent intent2 = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
      intent2.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(Environment.getExternalStorageDirectory(),
              "head.jpg")));
      startActivityForResult(intent2, 2);//采用ForResult打开
      break;
    default:
      break;
    }
  }
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
    case 1:
      if (resultCode == RESULT_OK) {
        cropPhoto(data.getData());//裁剪图片
      }

      break;
    case 2:
      if (resultCode == RESULT_OK) {
        File temp = new File(Environment.getExternalStorageDirectory()
            + "/head.jpg");
        cropPhoto(Uri.fromFile(temp));//裁剪图片
      }

      break;
    case 3:
      if (data != null) {
        Bundle extras = data.getExtras();
        head = extras.getParcelable("data");
        if(head!=null){
          /**
           * 上传服务器代码
           */
          setPicToView(head);//保存在SD卡中
          ivHead.setImageBitmap(head);//用ImageView显示出来
        }
      }
      break;
    default:
      break;

    }
    super.onActivityResult(requestCode, resultCode, data);
  };
  /**
   * 调用系统的裁剪
   * @param uri
   */
  public void cropPhoto(Uri uri) {
    Intent intent = new Intent("com.android.camera.action.CROP");
    intent.setDataAndType(uri, "image/*");
    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", 150);
    intent.putExtra("outputY", 150);
    intent.putExtra("return-data", true);
    startActivityForResult(intent, 3);
  }
  private void setPicToView(Bitmap mBitmap) {
     String sdStatus = Environment.getExternalStorageState();  
        if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用  
               return;  
           }  
    FileOutputStream b = null;
    File file = new File(path);
    file.mkdirs();// 创建文件夹
    String fileName =path + "head.jpg";//图片名字
    try {
      b = new FileOutputStream(fileName);
      mBitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件

    } catch (FileNotFoundException e) {
      e.printStackTrace();
    } finally {
      try {
        //关闭流
        b.flush();
        b.close();
      } catch (IOException e) {
        e.printStackTrace();
      }

    }
}
}

上面的注释已经很详细了，就这些

对了不要忘记加权限：

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

​​源码下载​​