android - 从 Activity 中调用相机，捕获图像并上传到服务器

Question

在我的应用程序中，我有一个调用相机的按钮 1，在捕获图像后，它必须保存到设备库中。当我点击 button2 时，它必须打开图库，并要求选择一张图片。选择后，它必须显示在这些按钮下方的 imageView 上。

这是我的代码:

package com.android.imageuploading;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class ImageUploadingActivity extends Activity {
    private static final int REQUEST_CODE = 1;
    private Bitmap bitmap;
    private ImageView imageView;
    private Button button_1;
    public int TAKE_PICTURE = 1;
    private Button button_2;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        imageView = (ImageView) findViewById(R.id.image);
        button_1 = (Button) findViewById(R.id.button1);
        button_1.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {

                Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
                startActivityForResult(intent, TAKE_PICTURE);

            }
        });
        button_2 = (Button) findViewById(R.id.button2);
        button_2.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {

                pickImage(getCurrentFocus());
            }
        });
    }

    public void pickImage(View view) {
        Intent intent = new Intent();
        intent.setType("image/*");
        intent.setAction(Intent.ACTION_GET_CONTENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        startActivityForResult(intent, REQUEST_CODE);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_CODE && resultCode == Activity.RESULT_OK)
            try {
                // We need to recyle unused bitmaps
                if (bitmap != null) {
                    bitmap.recycle();
                }
                InputStream stream = getContentResolver().openInputStream(
                        data.getData());
                bitmap = BitmapFactory.decodeStream(stream);
                stream.close();
                imageView.setImageBitmap(bitmap);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        super.onActivityResult(requestCode, resultCode, data);
    }

    public static boolean isIntentAvailable(Context context, String action) {
        final PackageManager packageManager = context.getPackageManager();
        final Intent intent = new Intent(action);
        List<ResolveInfo> list = packageManager.queryIntentActivities(intent,
                PackageManager.MATCH_DEFAULT_ONLY);
        return list.size() > 0;
    }
}

问题是，当我捕获图像时，它要求保存或丢弃。当我点击保存时，我的应用程序崩溃了，提示:

java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=Intent { act=inline-data (has extras) }} to activity {com.android.imageuploading/com.android.imageuploading.ImageUploadingActivity}: java.lang.NullPointerException

我需要在哪里更改代码？

Answer 1

在我的例子中，我使用这个:当我点击保存按钮时，图片被保存并在 filePath 变量中返回我的路径。

String filePath =
        Environment.getExternalStorageDirectory() +"/your_image_name.jpeg";
File file = new File(filePath);
Uri output = Uri.fromFile(file);
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, output);

在 onactivityresul() 中我使用这个“filePath”。