I am new to Android development, and I am working on a media player app as a learning experience. I am currently trying to add a menu view that utilizes album art in a gridview. Here is my code:
public class coverMenu extends Activity {
private Cursor audioCursor;
public String artistInput;
private static final String TAG = "coverMenu";
@开发者_如何学JAVAOverride
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.cover);
Bundle data = this.getIntent().getExtras();
String artistKey = data.getString("artistPass");
Toast.makeText(this, artistKey, Toast.LENGTH_LONG).show();
audioCursor = getContentResolver().query(MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI, null,
MediaStore.Audio.Albums.ARTIST + "='" + artistKey + "'", null,MediaStore.Audio.Albums.ALBUM + " ASC");
startManagingCursor(audioCursor);
String[]from = new String[]{MediaStore.Audio.Albums.ALBUM_ART};
int[] to = new int []{android.R.id.text1};
ListAdapter mAdapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1,
audioCursor, from, to);
GridView gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(mAdapter);
My problem is that the grid item now lists the path to the art, but does not show it. Can anyone help me by explaining how to parse this into a bitmap and send it to the gridview?
I have spent some time looking at the stock Android music player, but cannot find a simple solution to this.
Any help is appreciated.
[Latest Debug:]
DalvikVM[localhost:8615]
Thread [<3> main] (Suspended (exception RuntimeException))
ActivityThread.performLaunchActivity(ActivityThread$ActivityRecord, Intent) line: 2496
ActivityThread.handleLaunchActivity(ActivityThread$ActivityRecord, Intent) line: 2512
ActivityThread.access$2200(ActivityThread, ActivityThread$ActivityRecord, Intent) line: 119
ActivityThread$H.handleMessage(Message) line: 1863
ActivityThread$H(Handler).dispatchMessage(Message) line: 99
Looper.loop() line: 123
ActivityThread.main(String[]) line: 4363
Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]
Method.invoke(Object, Object...) line: 521
ZygoteInit$MethodAndArgsCaller.run() line: 860
ZygoteInit.main(String[]) line: 618
NativeStart.main(String[]) line: not available [native method]
Thread [<13> Binder Thread #2] (Running)
Thread [<11> Binder Thread #1] (Running)
Thread [<15> Binder Thread #3] (Running)
You need to create a custom adapter class that returns a populated grid view item based on the cursor's position. Here's a pretty crude example.
custom_grid_item.xml:
<LinearLayout android:id="@+id/LinearLayout01"
android:layout_width="fill_parent" android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView android:id="@+id/album_image"
android:layout_height="wrap_content" android:layout_width="wrap_content">
</ImageView>
</LinearLayout>
MySimpleListAdapter.java:
import java.io.File;
import android.content.Context;
import android.database.Cursor;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.SimpleCursorAdapter;
import android.widget.ImageView.ScaleType;
public class MySimpleListAdapter extends SimpleCursorAdapter {
private Context mContext;
public MySimpleListAdapter(Context context, int layout, Cursor c,
String[] from, int[] to) {
super(context, layout, c, from, to);
mContext = context;
}
public View getView(int position, View convertView, ViewGroup parent) {
View v;
ImageView iv;
if (convertView != null)
v = convertView;
else {
LayoutInflater layout = LayoutInflater.from(mContext);
v = layout.inflate(R.layout.custom_grid_item, null);
}
this.getCursor().moveToPosition(position);
iv = (ImageView) v.findViewById(R.id.album_image);
iv.setImageURI(Uri.fromFile(new File(this.getCursor().getString(9))));
iv.setScaleType(ScaleType.CENTER_INSIDE);
return v;
}}
Activity:
import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.provider.MediaStore;
import android.widget.GridView;
import android.widget.Toast;
public class CoverMenu extends Activity {
private Cursor audioCursor;
public String artistInput;
private static final String TAG = "coverMenu";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Set to some artist you know
String artistKey = "Devo";
Toast.makeText(this, artistKey, Toast.LENGTH_LONG).show();
audioCursor = getContentResolver().query(
MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI, null,
MediaStore.Audio.Albums.ARTIST + "='" + artistKey + "'", null,
MediaStore.Audio.Albums.ALBUM + " ASC");
startManagingCursor(audioCursor);
String[] from = new String[] { MediaStore.Audio.Albums.ALBUM_ART };
int[] to = new int[] { android.R.id.text1 };
MySimpleListAdapter mAdapter = new MySimpleListAdapter(this,
android.R.layout.simple_list_item_1, audioCursor, from, to);
GridView gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(mAdapter);
}}
Check out this nice video from Google I/O on creating custom listviews, it will be a big help to you in the future.
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