我已经实现了Gridview，但是电话库中的图像没有出现在特定的GridView中。 滚动似乎足够大，因为右侧出现的滚动条会向下滚动到底部。那为什么我看不到图像。
GalleryGridAdapter.java
package com.test.Adapter;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v4.widget.CursorAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.GridView;
import android.widget.ImageView;
import com.test.R;
public class GalleryGridAdapter extends CursorAdapter
{
private Context mContext;
private Cursor mCursor;
private int mColumnIndex;
private ImageView imageView;
@SuppressWarnings("deprecation")
public GalleryGridAdapter(Context context, Cursor c, int ci) {
super(context, c);
mContext = context;
mCursor = c;
mColumnIndex = ci;
}
@Override
public void bindView(View view, Context context, Cursor curs)
{
ImageView imageView = (ImageView) view;
int id = curs.getInt(mColumnIndex);
imageView.setImageURI( Uri.withAppendedPath(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,
String.valueOf(id)));
imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
}
@Override
public View newView(Context context, Cursor curs, ViewGroup parent)
{
return new ImageView(context);
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
public int mygetItemId(int position) {
return 0;
}
}
MyActivity.java
String[] projection = {MediaStore.Images.Thumbnails._ID, MediaStore.Images.Thumbnails.DATA};
final Cursor cursor = context.getContentResolver().query(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, projection, null, null,
MediaStore.Images.Thumbnails.IMAGE_ID);
int columnIndex = 0;
if (cursor != null) {
columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Images.Thumbnails._ID);
GridView gridview = (GridView) findViewById(R.id.gridViewGallery);
gridview.setAdapter(new GalleryGridAdapter(getApplicationContext(), cursor, columnIndex));
gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Log.e("selected Image",cursor.getColumnName(i)+"");
}
});
}
答案 0 :(得分：0)
使用xml代码，如：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:background="@drawable/bg_child">
<FrameLayout android:id="@+id/FrameLayout01"
android:layout_width="fill_parent" android:layout_height="fill_parent">
<FrameLayout android:id="@+id/LinearLayout01"
android:layout_gravity="top" android:layout_height="50dp" android:layout_width="fill_parent">
<TextView android:id="@+id/TextView01"
android:layout_width="wrap_content" android:layout_height="wrap_content" android:textStyle="bold" android:layout_gravity="center_vertical" android:layout_marginLeft="30dp" android:gravity="center_vertical" android:drawableLeft="@drawable/photo_frame" android:textColor="@color/grey" android:text="@string/photogallery_txt"></TextView>
<Button android:layout_gravity="right" android:id="@+id/btnMoreInfo" android:layout_marginRight="5dp" android:layout_marginTop="5dp" android:textStyle="bold" android:background="@drawable/my_child_button" android:layout_width="100dp" android:layout_height="40dp" android:text="@string/moreinfo_txt"></Button>
</FrameLayout>
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:columnWidth="90dp"
android:numColumns="auto_fit" android:verticalSpacing="10dp"
android:horizontalSpacing="10dp" android:stretchMode="columnWidth"
android:gravity="center" android:layout_gravity="bottom"
android:layout_marginTop="50dp"/>
</FrameLayout>
使用代码如：
public class GalleryPage extends Activity {
private static Uri[] mUrls = null;
private static String[] strUrls = null;
private String[] mNames = null;
private GridView gridview = null;
private Cursor cc = null;
private Button btnMoreInfo = null;
private ProgressDialog myProgressDialog = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.gallery);
btnMoreInfo = (Button) findViewById(R.id.btnMoreInfo);
// It have to be matched with the directory in SDCard
cc = this.getContentResolver().query(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI, null, null, null,
null);
if (cc != null) {
myProgressDialog = new ProgressDialog(GalleryPage.this);
myProgressDialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
myProgressDialog.setMessage(getResources().getString(R.string.pls_wait_txt));
myProgressDialog.show();
new Thread() {
public void run() {
try {
cc.moveToFirst();
mUrls = new Uri[cc.getCount()];
strUrls = new String[cc.getCount()];
mNames = new String[cc.getCount()];
for (int i = 0; i < cc.getCount(); i++) {
cc.moveToPosition(i);
mUrls[i] = Uri.parse(cc.getString(1));
strUrls[i] = cc.getString(1);
mNames[i] = cc.getString(3);
//Log.e("mNames[i]",mNames[i]+":"+cc.getColumnCount()+ " : " +cc.getString(3));
}
} catch (Exception e) {
}
myProgressDialog.dismiss();
}
}.start();
gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(new ImageAdapter(this));
gridview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
Intent i = new Intent(GalleryPage.this, BigImage.class);
Log.e("intent : ", ""+position);
i.putExtra("imgUrls", strUrls);
i.putExtra("position", position);
startActivity(i);
}
});
}
btnMoreInfo.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent i = new Intent(GalleryPage.this, ChildLogin.class);
startActivity(i);
}
});
}
/**
* This class loads the image gallery in grid view.
*
*/
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public int getCount() {
return cc.getCount();
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(R.layout.galchild, null);
try {
ImageView imageView = (ImageView) v.findViewById(R.id.ImageView01);
//imageView.setScaleType(ImageView.ScaleType.FIT_XY);
// imageView.setPadding(8, 8, 8, 8);
Bitmap bmp = decodeURI(mUrls[position].getPath());
//BitmapFactory.decodeFile(mUrls[position].getPath());
imageView.setImageBitmap(bmp);
//bmp.
TextView txtName = (TextView) v.findViewById(R.id.TextView01);
txtName.setText(mNames[position]);
} catch (Exception e) {
}
return v;
}
}
@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
FlurryAgent.onStartSession(this, "***");
}
/**
* This method is to scale down the image
*/
public Bitmap decodeURI(String filePath){
Options options = new Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filePath, options);
// Only scale if we need to
// (16384 buffer for img processing)
Boolean scaleByHeight = Math.abs(options.outHeight - 100) >= Math.abs(options.outWidth - 100);
if(options.outHeight * options.outWidth * 2 >= 16384){
// Load, scaling to smallest power of 2 that'll get it <= desired dimensions
double sampleSize = scaleByHeight
? options.outHeight / 100
: options.outWidth / 100;
options.inSampleSize =
(int)Math.pow(2d, Math.floor(
Math.log(sampleSize)/Math.log(2d)));
}
// Do the actual decoding
options.inJustDecodeBounds = false;
options.inTempStorage = new byte[512];
Bitmap output = BitmapFactory.decodeFile(filePath, options);
return output;
}
}