嘗試運行hellogridview時出現錯誤

Question

嘗試從Android網站運行hellogridview時出現一些錯誤。

GridView.java

包com.GridView;

導入android.app.Activity; 導入android.os.Bundle;

public class GridView extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        GridView 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){
                Toast.makeText(HelloGridView.this, "" + position, Toast.LENGTH_SHORT).show();
            }
        });
    }
}

此語句有誤
(GridView) findViewById(R.id.gridview)錯誤與
setAdapter()
錯誤
OnItemClickListener()
錯誤
AdapterView<?>
錯誤
HelloGridView錯誤與
}）;

所有這些都是從android網站復制的。

圖像適配器.java

package com.GridView;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.BaseAdapter;
import android.widget.ImageView;

public class ImageAdapter extends BaseAdapter {
    private Context mContext;

    public ImageAdapter(Context c) {
        mContext = c;
    }

    public int getCount() {
        return mThumbIds.length;
    }

    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 getView1(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {  // if it's not recycled, initialize some attributes
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new LayoutParams(85, 85));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(8, 8, 8, 8);
        } else {
            imageView = (ImageView) convertView;
        }

        imageView.setImageResource(mThumbIds[position]);
        return imageView;
    }

    // references to our images
    private Integer[] mThumbIds = {
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7,
            R.drawable.sample_0, R.drawable.sample_1,
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7,
            R.drawable.sample_0, R.drawable.sample_1,
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7
    };

    @Override
    public View getView(int arg0, View arg1, ViewGroup arg2) {
        // TODO Auto-generated method stub
        return null;
    }
}

main.xml中

<?xml version="1.0" encoding="utf-8"?
<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:gravity="center"
    android:horizontalSpacing="10dp"
    android:numColumns="auto_fit"
    android:stretchMode="columnWidth"
    android:verticalSpacing="10dp" />

Answer 1

我注意到您尚未導入Android GridView類和AdapterView類。 將以下導入添加到GridView.java中：

import android.widget.GridView;
import android.widget.AdapterView;

Answer 2

您的編譯器變得非常混亂。 您已將您的類命名為GridView，但應根據示例將其命名為HelloGridView。 GridView是屬於Android API的類。 我建議刪除項目，然后完全按照說明重新開始，因為否則您將需要手動更改其他一些內容才能使應用程序再次運行。 由於他們的示例也錯過了所有必需的導入行，因此您必須自己添加這些行。 您可以通過在Eclipse中按ctrl + shift + o來執行此操作。