Gridview 不工作（不幸的是应用程序已停止错误）

Question

以下是我要创建的网格视图的代码。应用程序已安装在设备中，但不幸的是显示停止错误

这是我的带有适配器的网格代码

    package com.anis.project_test1;

    import android.app.Activity;
    import android.os.Bundle;
    import android.widget.GridView;
    import android.content.Context;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.ImageView;
    import android.widget.TextView;


public class Grid extends Activity {

static final String[] ITEM_LIST = new String[] { "Timetable", "Coursework",
    "Exam" };


GridView gridView;

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

    gridView.setAdapter(new ImageAdapter(this,ITEM_LIST ));
}

 class ImageAdapter extends BaseAdapter
{
    private Context context;
    private final String[] itemName;

    public ImageAdapter(Context context, String[] itemName) {
        this.context = context;
        this.itemName = itemName;
    }


    public int getCount() {

        return itemName.length;
    }


    public Object getItem(int position) {

        return null;
    }


    public long getItemId(int position) {

        return 0;
    }


    public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View gridView = null;

        if (convertView==null)
                {
                    gridView = new View(context);
                    gridView = inflater.inflate(R.layout.griditem, null);

                    TextView textView = (TextView) gridView.findViewById(R.id.grid_label);
                    textView.setText(itemName[position]);

                    ImageView imageView = (ImageView) gridView.findViewById(R.id.grid_image);

                    String item = itemName[position];


                if (item.equalsIgnoreCase("timetable")) 
                {
                    imageView.setImageResource(R.drawable.timetable);

                }

                else if (item.equalsIgnoreCase("coursework"))   
                {
                    imageView.setImageResource(R.drawable.coursework);
                }

                else if (item.equalsIgnoreCase("exam")) 
                {
                    imageView.setImageResource(R.drawable.test);
                }

                else 
                {
                    gridView = (View) convertView;

                }
                return gridView;
                }
        return gridView;



    }

}


}

这是我的 gridview xml 文件

 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent" >

  <GridView
     android:id="@+id/gridview"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_alignParentLeft="true"
     android:layout_alignParentTop="true"
     android:horizontalSpacing="10dp"
     android:verticalSpacing="10dp"
     android:numColumns="auto_fit"
     android:stretchMode="spacingWidthUniform"      
     android:columnWidth="114dp" >

 </GridView>

这是每个网格块中项目的 xml 文件。

  <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent" 
 android:orientation="vertical"
 android:padding="5dp" >

<ImageView
    android:id="@+id/grid_image"
    android:layout_width="114dp"
    android:layout_height="114dp"
    android:layout_gravity="center"
    android:src="@drawable/timetable" />

 <TextView
    android:id="@+id/grid_label"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_marginTop="5dp"
    android:text="timetable"
    android:textColor="#000000"
    android:textSize="20dp" />


</LinearLayout>

这是我的清单文件

 <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.anis.project_test1"
 android:versionCode="1"
 android:versionName="1.0" >

 <uses-sdk
    android:minSdkVersion="9"
    android:targetSdkVersion="18" />

 <application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.anis.project_test1.Splash"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".Grid"></activity>
</application>

</manifest>

Answer 1

试试这个方法，希望能帮助你解决问题。

public class Grid extends Activity{

    static final String[] ITEM_LIST = new String[] { "Timetable", "Coursework",
            "Exam" };


    GridView gridView;

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

        gridView.setAdapter(new ImageAdapter(this,ITEM_LIST ));
    }

    class ImageAdapter extends BaseAdapter
    {
        private Context context;
        private final String[] itemName;

        public ImageAdapter(Context context, String[] itemName) {
            this.context = context;
            this.itemName = itemName;
        }


        public int getCount() {

            return itemName.length;
        }


        public Object getItem(int position) {

            return itemName[position];
        }


        public long getItemId(int position) {

            return position;
        }


        public View getView(int position, View convertView, ViewGroup parent) {

            ViewHolder holder;
            if (convertView==null) {
                holder = new ViewHolder();
                convertView = LayoutInflater.from(context).inflate(R.layout.griditem, null);
                holder.textView = (TextView) convertView.findViewById(R.id.grid_label);
                holder.imageView = (ImageView) convertView.findViewById(R.id.grid_image);

                convertView.setTag(holder);
            }else{
                holder = (ViewHolder)convertView.getTag();
            }

            holder.textView.setText(itemName[position]);

            if (itemName[position].equalsIgnoreCase("timetable")){
                holder.imageView.setImageResource(R.drawable.timetable);
            }else if (itemName[position].equalsIgnoreCase("coursework")){
                holder.imageView.setImageResource(R.drawable.coursework);
            }else{
                holder.imageView.setImageResource(R.drawable.test);
            }

            return convertView;
        }

        class ViewHolder{
            TextView textView;
            ImageView imageView;
        }
    }
}