Question

我需要在屏幕上显示手机中的图片。我目前正在tyhe手机上获得图片的所有路径（见下文）。现在我需要在屏幕上显示它们。有什么想法吗？

 ArrayList<String> photoPaths = new ArrayList<String>();        
photoPaths = getAllPhotos(Environment.getExternalStorageDirectory(), photoPaths);
    Log.e(ACCESSIBILITY_SERVICE, "photo array!"+photoPaths);
    Log.e(ACCESSIBILITY_SERVICE, "photo path size"+photoPaths.size());

    for(int i=0;i<photoPaths.size();i++)
    {
        File imgFile = new  File(photoPaths.get(i));
        if(imgFile.exists())
        {

  Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());

 ImageView myImage = (ImageView) findViewById(R.id.picimageView);
 myImage.setImageBitmap(myBitmap);//NEED TO DISPLAY ALL PICTURES 

        }

Answer 1

下面是一个Android示例，介绍如何访问和显示存储在SD卡上的图像。

主要思想是使用MediaStore类，它是一个媒体提供程序，包含内部和外部存储设备（如SD卡）上所有可用媒体的数据。适配器用作数据和视图之间的桥梁。

package blog.android.sdcard;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.AdapterView.OnItemClickListener;

/**
 * Displays images from an SD card.
 */
public class SDCardImagesActivity extends Activity {

    /**
     * Cursor used to access the results from querying for images on the SD card.
     */
    private Cursor cursor;
    /*
     * Column index for the Thumbnails Image IDs.
     */
    private int columnIndex;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.sdcard);

        // Set up an array of the Thumbnail Image ID column we want
        String[] projection = {MediaStore.Images.Thumbnails._ID};
        // Create the cursor pointing to the SDCard
        cursor = managedQuery( MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,
                projection, // Which columns to return
                null,       // Return all rows
                null,
                MediaStore.Images.Thumbnails.IMAGE_ID);
        // Get the column index of the Thumbnails Image ID
        columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Thumbnails._ID);

        GridView sdcardImages = (GridView) findViewById(R.id.sdcard);
        sdcardImages.setAdapter(new ImageAdapter(this));

        // Set up a click listener
        sdcardImages.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView parent, View v, int position, long id) {
                // Get the data location of the image
                String[] projection = {MediaStore.Images.Media.DATA};
                cursor = managedQuery( MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                        projection, // Which columns to return
                        null,       // Return all rows
                        null,
                        null);
                columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
                cursor.moveToPosition(position);
                // Get image filename
                String imagePath = cursor.getString(columnIndex);
                // Use this path to do further processing, i.e. full screen display
            }
        });
    }

    /**
     * Adapter for our image files.
     */
    private class ImageAdapter extends BaseAdapter {

        private Context context;

        public ImageAdapter(Context localContext) {
            context = localContext;
        }

        public int getCount() {
            return cursor.getCount();
        }
        public Object getItem(int position) {
            return position;
        }
        public long getItemId(int position) {
            return position;
        }
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView picturesView;
            if (convertView == null) {
                picturesView = new ImageView(context);
                // Move cursor to current position
                cursor.moveToPosition(position);
                // Get the current value for the requested column
                int imageID = cursor.getInt(columnIndex);
                // Set the content of the image based on the provided URI
                picturesView.setImageURI(Uri.withAppendedPath(
                        MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, "" + imageID));
                picturesView.setScaleType(ImageView.ScaleType.FIT_CENTER);
                picturesView.setPadding(8, 8, 8, 8);
                picturesView.setLayoutParams(new GridView.LayoutParams(100, 100));
            }
            else {
                picturesView = (ImageView)convertView;
            }
            return picturesView;
        }
    }
}

主要活动的布局如下所示：

<?xml version="1.0" encoding="utf-8"?>
<GridView xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@+id/sdcard"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:padding="10dp"
    android:verticalSpacing="10dp"
    android:horizontalSpacing="10dp"
    android:numColumns="auto_fit"
    android:columnWidth="90dp"
    android:stretchMode="columnWidth"
    android:gravity="center"
/>

修改为了从SD卡中查看缩略图图像，Android需要首先创建它们，因此您应该启动预装的Gallery应用程序，并打开sdcard文件夹，该文件夹将自动为存储在SD卡上的图像创建缩略图。这是SDK的当前缺点，将在以后的版本中修复（http://groups.google.com/group/android-developers/browse_thread/thread/3f01b284e2537312/fa9487d19db4907e）。

出于某种原因，如果您使用

MediaStore.Images.Thumbnails.IMAGE_ID

与上述代码的上一版本一样，图像并不总是显示在屏幕上。改为

MediaStore.Images.Thumbnails._ID

似乎解决了这个问题。我会更多地了解为什么并回复你。此外，一些图像附加了错误的路径。我从
更改了光标对象的创建
cursor = managedQuery( MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, projection, // Which columns to return null, // Return all rows null, null);

要

cursor = managedQuery( MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, projection, // Which columns to return null, // Return all rows null, MediaStore.Images.Thumbnails.IMAGE_ID);

享受.. !!!

显示arraylist <string>（图片的路径名称）</string>中的图片

1 个答案: