一. 前言

這章將從相簿和拍照獲取圖片，並顯示成圓形圖片。

二. 準備

首先需要做一個圓形的顯示區域，我用的是CircleImageView開源庫

CircleImageView原始碼地址：https://github.com/hdodenhof/CircleImageView

（1）下載CircleImageView原始碼

（2）將CircleImageView.class新增到你的專案中，一般存在工具類中

（3）新增後會出現一些錯誤資訊，這時我們需要將CircleImageView原始碼包中res/values/attrs.xml新增到我們的res/values下

注：attrs.xml中的引數與CircleImageView.class有關聯，所有要修改就一起改。

三. 實現

activity.xml佈局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
    <com.jmg.utils.CircleImageView
 
android:id="@+id/touxiang"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:src="@mipmap/logo_image"
app:civ_border_width="2dp"
app:civ_border_color="@color/colorBlack" />
</RelativeLayout>

MainActivity.xml

import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import com.jmg.utils.CircleImageView;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {

    private CircleImageView imageView;
    private Bitmap head;// 頭像Bitmap
private static String path = "/sdcard/myHead/";// sd路徑
@Override
public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageView = (CircleImageView) findViewById(R.id.touxiang);
imageView.setOnClickListener(new View.OnClickListener() {
            @Override
public void onClick(View view) {
                showTypeDialog();
}
        });
}

    @Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode) {
            case 1:
                if (resultCode == RESULT_OK) {
                    cropPhoto(data.getData());// 裁剪圖片
}

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

                break;
            case 3:
                if (data != null) {
                    Bundle extras = data.getExtras();
head = extras.getParcelable("data");
                    if (head != null) {
                        setPicToView(head);// 儲存在SD卡中
imageView.setImageBitmap(head);// 用ImageButton顯示出來
}
                }
                break;
            default:
                break;
}
        super.onActivityResult(requestCode, resultCode, data);
}

    private void showTypeDialog() {
        //顯示對話方塊
AlertDialog.Builder builder = new AlertDialog.Builder(this);
        final AlertDialog dialog = builder.create();
View view = View.inflate(this, R.layout.dialog_select, null);
TextView tv_select_gallery = (TextView) view.findViewById(R.id.tv_select_gallery);
TextView tv_select_camera = (TextView) view.findViewById(R.id.tv_select_camera);
tv_select_gallery.setOnClickListener(new View.OnClickListener() {// 在相簿中選取
@Override
public void onClick(View v) {
                Intent intent1 = new Intent(Intent.ACTION_PICK, null);
//開啟檔案
intent1.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
startActivityForResult(intent1, 1);
dialog.dismiss();
}
        });
tv_select_camera.setOnClickListener(new View.OnClickListener() {// 呼叫照相機
@Override
public void onClick(View v) {
                Intent intent2 = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent2.putExtra(MediaStore.EXTRA_OUTPUT,
Uri.fromFile(new File(Environment.getExternalStorageDirectory(), "head.jpg")));
startActivityForResult(intent2, 2);// 採用ForResult開啟
dialog.dismiss();
}
        });
dialog.setView(view);
dialog.show();
}

    /**
     * 呼叫系統的裁剪功能
*
     * @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 是寬高的比例
intent.putExtra("aspectX", 1);
intent.putExtra("aspectY", 1);
// outputX outputY 是裁剪圖片寬高
intent.putExtra("outputX", 250);
intent.putExtra("outputY", 250);
intent.putExtra("return-data", true);
startActivityForResult(intent, 3);
}

    private void setPicToView(Bitmap mBitmap) {
        String sdStatus = Environment.getExternalStorageState();
        if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 檢測sd是否可用
return;
}
        FileOutputStream b = null;
File file = new File(path);
file.mkdirs();// 建立資料夾
String fileName = path + "head.jpg";// 圖片名字
try {
            b = new FileOutputStream(fileName);
mBitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把資料寫入檔案
} catch (FileNotFoundException e) {
            e.printStackTrace();
} finally {
            try {
                // 關閉流
if (b != null) {
                    b.flush();
b.close();
}
            } catch (IOException e) {
                e.printStackTrace();
}
        }
    }
}

新增MyApplication.class

import android.app.Application;
import android.os.StrictMode;
public class MyApplication extends Application {

    @Override
public void onCreate() {
        super.onCreate();
// android 7.0系統解決拍照的問題
StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
StrictMode.setVmPolicy(builder.build());
builder.detectFileUriExposure();
}
}

然後再AndroidManifest.xml中新增

<application
android:name=".MyApplication"    //新增這一行

後續還會新增各手機獲取相簿圖片或拍照會出現的問題及解決辦法。

The End!

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