首先我們看佈局程式碼的檔案：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
    <Button
        android:id="@+id/bu_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Take Photo"/>
    <Button
        android:id="@+id/choose_from_album"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="chose from Album"/>
    <ImageView
        android:id="@+id/picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"/>
</LinearLayout>
 

圖中有兩個按鈕,一個是用來啟動照相機的,另一個是用來選擇本地照片的,還有一個ImageView控制元件,是用來顯示照片的

然後就是主函式中的程式碼：

package com.example.pc_ly.cameraalbumtest;

import android.Manifest;
import android.annotation.TargetApi;
import android.content.ContentUris;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Build;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.concurrent.Callable;

import static android.R.attr.handle;

public class MainActivity extends AppCompatActivity {
    public static final int TAKE_PHOTO=1;
    public static final int CHOOSE_PHOTO=2;
    private ImageView picture;
    private Uri imageUri;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button button=(Button)findViewById(R.id.bu_1);
        picture=(ImageView)findViewById(R.id.picture);
        Button choose=(Button)findViewById(R.id.choose_from_album);
        choose.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {//確認是否有許可權開啟
                if(ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
                    ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
                }
                else{
                    openAlbum();
                }
            }
        });
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                File outputImage=new File(getExternalCacheDir(),"output_image.jpg");//用於存放攝像頭拍攝的照片
                try{
                    if (outputImage.exists()){
                        outputImage.delete();
                    }
                    outputImage.createNewFile();
                }catch (IOException e){
                    e.printStackTrace();
                }
                if (Build.VERSION.SDK_INT>=24){//根據android的版本對URI執行操作
                    imageUri= FileProvider.getUriForFile(MainActivity.this,"com.example.pc_ly.cameraalbumtest.fileprovider",outputImage);}
                else{imageUri=Uri.fromFile(outputImage);
                }
                Intent intent=new Intent("android.media.action.IMAGE_CAPTURE");//系統會找到能夠找到能響應這個intent程式去執行
                intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
                startActivityForResult(intent,TAKE_PHOTO);
            }
        });
    }
    @Override
    protected void onActivityResult(int requestCode,int resultCode,Intent data){//如果拍照成功，則會將照片顯示在容器中
        switch (requestCode){
            case TAKE_PHOTO:
                if(resultCode==RESULT_OK){
                    try{
                        Bitmap bitmap= BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
                        picture.setImageBitmap(bitmap);
                    }catch (FileNotFoundException e){
                        e.printStackTrace();
                    }
                }
                break;
            case CHOOSE_PHOTO:
                if(resultCode==RESULT_OK){
                    //判斷手機版本號
                    if(Build.VERSION.SDK_INT>=19){
                        handleImageOnKitKat(data);
                    }
                    else{
                        handleImageBeforeKitKat(data);
                    }
                }
            default:
                break;
        }
    }
    public void openAlbum(){
        Intent intent=new Intent("android.intent.action.GET_CONTENT");
        intent.setType("image/*");
        startActivityForResult(intent,CHOOSE_PHOTO);//開啟相簿
    }
    public void onRequestPermissionResult(int requestCode,String[] permissions,int[] grantResults){//看是否許可權已經開啟
        switch (requestCode){
            case 1:
                if(grantResults.length>0&&grantResults[0]==PackageManager.PERMISSION_GRANTED){
                    openAlbum();
                }
                else{
                    Toast.makeText(this,"You denied the permission",Toast.LENGTH_SHORT).show();
                }
                break;
            default:
        }
    }
    @TargetApi(19)
    private void handleImageOnKitKat(Intent data){//根據版本對uri進行解析
        String imagePath=null;
        Uri uri=data.getData();
        if(DocumentsContract.isDocumentUri(this,uri)){
            //如果是document型別的Uri，則通過document id處理
            String docId=DocumentsContract.getDocumentId(uri);
            if("com.android.providers.media.documents".equals(uri.getAuthority())){
                String id=docId.split(":")[1];//解析出數字格式的id
                String selection=MediaStore.Images.Media._ID+"="+id;
                imagePath=getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,selection);
            }
            else if("com.android.providers.downloads.documents".equals(uri.getAuthority())){
                Uri contentUri= ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"),Long.valueOf(docId));
                imagePath=getImagePath(contentUri,null);
            }
            else if("content".equalsIgnoreCase(uri.getScheme())){
                imagePath=getImagePath(uri,null);
            }
            else if("file".equalsIgnoreCase(uri.getScheme())){
                imagePath=uri.getPath();
            }
        }
    }
    private void handleImageBeforeKitKat(Intent data){//老版本的解析
        Uri uri=data.getData();
        String imagePath=getImagePath(uri,null);
        displayImage(imagePath);
    }
    private String getImagePath(Uri uri,String selection){//獲取路徑
        String path=null;
        Cursor cursor=getContentResolver().query(uri,null,selection,null,null);
        if(cursor!=null){
            if (cursor.moveToFirst()){
                path=cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
            }
            cursor.close();
        }
        return path;
    }
    private void displayImage(String imagePath){//展示照片
        if(imagePath!=null){
            Bitmap bitmap=BitmapFactory.decodeFile(imagePath);
            picture.setImageBitmap(bitmap);
        }
        else{
            Toast.makeText(this,"faild to get image",Toast.LENGTH_SHORT).show();
        }
    }
}

 

最後還有一個要注意一個重要的東西, 要申明一下許可權, 如下圖：

上面的註釋已經寫得很清楚了啦,我就不一一解釋了，下面來看效果圖：

執行之後是這個介面，然後我們點選take photo按鈕,就可以開啟照相機啦,如下圖：

然後我們點選CHOSE FROM ALBUM按鈕,就可以選擇照片檔案啦：

好啦,這次就到這裡啦，有什麼疑問的話歡迎和我留言呀

郵箱：[email protected]

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歡迎各位訪問哦，這次就到這裡啦！