Question

我希望在每个GridView Cell上显示相同的图像，但每次在两到三秒后显示。请尽力帮助我。提前致谢

PlayActivity.java

public class PlayActivity extends AppCompatActivity
{
private Intent intent;
private GridView gridView;
private int rangeFrom, rangeTo, counter, imageId=R.drawable.horse;
private String order;
private String[] list;
private Handler handler;
private int i;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_play);
    gridView = (GridView) findViewById(R.id.gridView);

    intent=getIntent();
    if(intent.getStringExtra("rangeFrom")!=null && intent.getStringExtra("rangeTo")!=null)
    {
        rangeFrom=Integer.parseInt(intent.getStringExtra("rangeFrom"));
        rangeTo=Integer.parseInt(intent.getStringExtra("rangeTo"));
    }
    counter=Integer.parseInt(intent.getStringExtra("counter"));
    order=intent.getStringExtra("order");


    Thread t1=new Thread(){
        public void run() {
            try {
                for(i= 1; i<=5; i++) {
                    gridView.deferNotifyDataSetChanged();
                    gridView.setAdapter(new PlayCustomAdapter(PlayActivity.this, i, imageId));
                    wait(2000);
                    gridView=null;
                    gridView=(GridView) findViewById(R.id.gridView);
                }
            }
            catch (Exception e) {
                e.printStackTrace();
            }
        }
    };
    t1.start();

}
}

PlayCustomAdapter.java

public class PlayCustomAdapter extends BaseAdapter
{
private Context context;
private int imageId, rangeTo;
private static LayoutInflater inflater=null;

public PlayCustomAdapter(PlayActivity playActivity, int rangeTo, int imageId) {
    context=playActivity;
    this.rangeTo=rangeTo;
    this.imageId=imageId;
    inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public int getCount() {
    return rangeTo;
}

@Override
public Object getItem(int position) {
    return position;
}

@Override
public long getItemId(int position) {
    return position;
}

public class Holder
{
    ImageView iv;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    Holder holder=new Holder();
    View rowview;
    rowview=inflater.inflate(R.layout.play_gridview_list, null);
    holder.iv=(ImageView) rowview.findViewById(R.id.imageView1);
    holder.iv.setImageResource(imageId);
    return rowview;
}
}

这是我的代码。我想要这样的输出。

This is the output which I am expecting

Answer 1

使用post delay handler

    public View getView(int position, View convertView, ViewGroup parent) {
    Holder holder=new Holder();
    View rowview;
    rowview=inflater.inflate(R.layout.play_gridview_list, null);
    holder.iv=(ImageView) rowview.findViewById(R.id.imageView1);
    Handler handler = new Handler();
    handler.postDelayed(new Runnable() {
        @Override
        public void run() {
            holder.iv.setImageResource(imageId);

        }
    },2000);
    return rowview;
}

Answer 2

以下是您的要求的完整工作示例。

在 MainActivity.java 中，

public class MainActivity extends AppCompatActivity
{
    private GridView gridView;
    private ArrayList<Integer> imagesList;
    private PlayCustomAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        gridView = (GridView) findViewById(R.id.gridView);
        gridView.deferNotifyDataSetChanged();
        imagesList = new ArrayList<Integer>();
        adapter = new PlayCustomAdapter(imagesList);
        gridView.setAdapter(adapter);

        // By using AsyncTask
        new LoadImagesTask().execute();
    }

    private class PlayCustomAdapter extends BaseAdapter
    {
        private ArrayList<Integer> imagesList;
        private LayoutInflater inflater = null;

        public PlayCustomAdapter(ArrayList<Integer> imagesList)
        {
            this.imagesList = imagesList;
            inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }

        @Override
        public int getCount()
        {
            return imagesList.size();
        }

        @Override
        public Object getItem(int position)
        {
            return imagesList.get(position);
        }

        @Override
        public long getItemId(int position)
        {
            return position;
        }

        public class Holder
        {
            ImageView iv;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent)
        {
            Holder holder = new Holder();
            View rowview;
            rowview = inflater.inflate(R.layout.play_gridview_list, null);
            holder.iv = (ImageView) rowview.findViewById(R.id.imageView1);
            holder.iv.setImageResource((int) getItem(position));
            return rowview;
        }
    }

    private class LoadImagesTask extends AsyncTask<Void, Integer, Void>
    {
        @Override
        protected Void doInBackground(Void... voids)
        {
            try
            {
                for (int i = 1; i <= 5; i++)
                {
                    // Here, I am getting launcher icon from resources.
                    publishProgress(R.mipmap.ic_launcher);
                    Thread.sleep(2000);
                }
            }
            catch (Exception ex)
            {
                ex.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onProgressUpdate(Integer... values)
        {
            super.onProgressUpdate(values);
            imagesList.add(values[0]);
            adapter.notifyDataSetChanged();
        }
    }
}

在 activity_main.xml 中，

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="esealed.com.testing123.MainActivity">
   <GridView
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:id="@+id/gridView"/>
</RelativeLayout>

在 play_gridview_list.xml ，

<?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">
<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView1"/>
</LinearLayout>

每两秒钟后逐个显示GridView Cell

2 个答案: