android上给应用设置用户头像（图片来自图库和现拍）

package com.xiaogang.imageheader;

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.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;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {
private static final int IMAGE_REQUEST_CODE = 0;
private static final int CAMERA_REQUEST_CODE = 1;
private static final int RESIZE_REQUEST_CODE = 2;

private static final String IMAGE_FILE_NAME = "header.jpg";

private ImageView mImageHeader;

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

setupViews();
}

private void setupViews() {
mImageHeader = (ImageView) findViewById(R.id.image_header);
final Button selectBtn1 = (Button) findViewById(R.id.btn_selectimage);
final Button selectBtn2 = (Button) findViewById(R.id.btn_takephoto);
selectBtn1.setOnClickListener(this);
selectBtn2.setOnClickListener(this);
}

@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_selectimage:
Intent galleryIntent = new Intent(Intent.ACTION_GET_CONTENT);
galleryIntent.addCategory(Intent.CATEGORY_OPENABLE);
galleryIntent.setType("image/*");
startActivityForResult(galleryIntent, IMAGE_REQUEST_CODE);
break;
case R.id.btn_takephoto:
if (isSdcardExisting()) {
Intent cameraIntent = new Intent(
"android.media.action.IMAGE_CAPTURE");
cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, getImageUri());
cameraIntent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 0);
startActivityForResult(cameraIntent, CAMERA_REQUEST_CODE);
} else {
Toast.makeText(v.getContext(), "请插入sd卡", Toast.LENGTH_LONG)
.show();
}
break;
}
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode != RESULT_OK) {
return;
} else {
switch (requestCode) {
case IMAGE_REQUEST_CODE:
resizeImage(data.getData());
break;
case CAMERA_REQUEST_CODE:
if (isSdcardExisting()) {
resizeImage(getImageUri());
} else {
Toast.makeText(MainActivity.this, "未找到存储卡，无法存储照片！",
Toast.LENGTH_LONG).show();
}
break;

case RESIZE_REQUEST_CODE:
if (data != null) {
showResizeImage(data);
}
break;
}
}

super.onActivityResult(requestCode, resultCode, data);
}

private boolean isSdcardExisting() {
final String state = Environment.getExternalStorageState();
if (state.equals(Environment.MEDIA_MOUNTED)) {
return true;
} else {
return false;
}
}

public void resizeImage(Uri uri) {
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setDataAndType(uri, "image/*");
intent.putExtra("crop", "true");
intent.putExtra("aspectX", 1);
intent.putExtra("aspectY", 1);
intent.putExtra("outputX", 150);
intent.putExtra("outputY", 150);
intent.putExtra("return-data", true);
startActivityForResult(intent, RESIZE_REQUEST_CODE);
}

private void showResizeImage(Intent data) {
Bundle extras = data.getExtras();
if (extras != null) {
Bitmap photo = extras.getParcelable("data");
Drawable drawable = new BitmapDrawable(photo);
mImageHeader.setImageDrawable(drawable);
}
}

private Uri getImageUri() {
return Uri.fromFile(new File(Environment.getExternalStorageDirectory(),
IMAGE_FILE_NAME));
}
}